Дисертації: "Two stage selection"

1

Yousef, Mohammed A. "Two-Stage SCAD Lasso for Linear Mixed Model Selection." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1558431514460879.

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2

Sands, John Stephen, and n/a. "Auditor Switching - A Two-Stage Decision Process: An Empirical Study of Australian Companies." Griffith University. Department of Accounting, Finance and Economics, 1996. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050901.152229.

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This dissertation is concerned with a primary and two secondary research issues. The primary issue pertains to the existence of a two-stage auditor switching decision process; that is the auditor change and the auditor selection stages. The two secondary issues concern the relative influence of variables within their respective decision stages. External auditors are engaged not only to comply with the Corporations Law requirement and Australian Stock Exchange membership conditions but also to reduce the degree of information risk assigned by financial statement users to financial statements prepared by auditee management. The decision to switch auditors may cause financial statement users to assign a higher degree of information risk to financial statements, i.e., the indirect costs of switching auditors. A substantial increase in these indirect costs may have occurred as the average rate that Australian publicly listed companies switch auditor has increased in recent years. However, prior research has provided inconsistent and inconclusive evidence with regard to the variables that influence auditees to switch auditors. To avoid mis-perceptions by financial statement users about the newly appointed auditors' attestation of the financial information prepared by auditees, a greater understanding is needed of the auditor switching decision process to assist in mitigating these indirect costs of switching auditors. In prior research the underlying suggestion why auditees switch auditors is the development of a mis-match of audit services demanded to the services supplied by the incumbent auditor. To overcome this mis-match, auditees after deciding to change auditors then select a specific audit firm that offers suitable services and possesses suitable characteristics. A suggested reason for the inconsistent findings of prior research is that there are two decision stages (auditor change and auditor selection) in the auditor switching decision process and past studies have examined, intentionally or otherwise, different decision stages. From a two decision stage perspective, there are three additional explanations for the inconsistent findings of prior research. These explanations are 1) the inappropriate use of surrogate measures for the decision stage studied, 2) the misuse of the terms auditor change, auditor selection and auditor switching, and 3) the inappropriate research methodology and instrument design employed. This absence of a 'shared agreement' among researchers about the two-stage auditor switching decision concept and misuse of terms may have confused not only researchers but also survey participants and readers of auditor switching literature thus contributing to the inconsistencies in prior evidence as well as perpetuating the inconsistent results where the readers are the future researchers. A review of the literature identified five characteristic variables of the incumbent and replacement audit firms that influence the auditor switching decision. Four variables (disagreements between auditees and auditors that result in, or are caused by, the issuance of a qualified audit report and recommendations from three external sources) in addition to the five incumbent auditor characteristics were found to influence only the auditor change decision. In addition to the five replacement auditor characteristic variables, a further five variables, involving audit firm image creation or other promotional activities, have been found to influence the auditor selection decision stage. A primary and two secondary problems regarding the auditor switching decision process are addressed (1) How and to what extent does the impact of the five auditor characteristics on Australian auditees' decisions to change auditors (to terminate the incumbent auditor's appointment) differ from that on auditees' decisions to select the replacement auditor? (2) How and to what extent are the nine variables used by Australian auditee management in the decision to change auditors (to terminate the incumbent auditors appointment)? (3) How and to what extent are the ten variables used by Australian auditee management in the decision to select a replacement auditor? The provision of evidence to support the two-stage auditor switching decision process may be achieved by jointly examining and identifying significant differences in the perceived influence of auditor characteristics across the two decision stages and a comparison of their rank order of influence within each stage. Three empirical models are constructed to investigate these three research questions. Using the MANOVA (within-subjects) design, the first model is to analyse each respondent's perception of the level of influence of each of the five auditor characteristic variables across the two decision stages. The second and third empirical models are using an one-way ANOVA design to test the influence of each of the respective independent variables (i.e., nine variables for the change decision and ten variables for the selection decision) on the respective dependent variable (i.e., the change decision or the selection decision). Fifty-three usable responses were received from Australian companies identified as voluntarily switching auditors for the reporting year ended 1990 and/or 1991. The data collected for analysis were provided by company executives of these companies. The major findings of this study are: 1) Two of the five auditor characteristics, 'level of audit quality' and 'suitability of non-audit services', differed significantly in their level of relative influence across the two decision stages. Furthermore, there was some support in the results for a perceived difference in the influence of a third auditor characteristic, 'size of audit fees', across both stages. 2) Significant differences were perceived in the level of influence of variables on the auditor change decision stage. The six most influential variables were the higher audit fees, the auditor's offices were not located near the auditee's geographically dispersed offices, the incumbent auditor's lack of industry specialisation, a higher audit quality was not provided, the non-audit services offered were unsuitable, and director's recommendations. 3) In the auditor selection decision stage, significant differences were perceived in the level of influence of variables. The six most influential variables were the lower fees, the recommendations of business colleagues, a higher quality audit can be provided, the suitability of range of non-audit services, the closeness of the auditor's offices to the auditee's geographically dispersed operations, and the availability of industry specialisation. 4) A comparison of the rank order of influence of auditor characteristic variables within each decision stage found variances exist for two variables 'closeness of auditor's offices to the auditee's operations' and 'the level of industry specialisation' across the two stages. 5) The significant difference in the level of influence of characteristics of the incumbent and replacement auditors in the first finding suggests that auditors are not perceived as providing homogeneous services. Furthermore, from the significant difference in these auditor characteristic variables within each decision stage in the second and third findings imply that the auditor characteristics of an auditor are not perceived as homogeneous. The following major conclusions are drawn from this study. The evidence from these major findings support the existence of a two-stage auditor switching decision process. The results also show that auditor switching decision makers' perceptions of the variables that influence auditor switching vary across the two decision stages and with the auditor change and auditor selection decisions. Finally, because the characteristics of the auditors vary in their perceived influence across both stages and within each decision stage, these variances suggest the auditor characteristics supplied are perceived to be heterogeneous. This perceived heterogeneity permits audit firms to differentiate their services offered and requires auditees to employ a two-stage auditor switching decision process.

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3

Sands, John Stephen. "Auditor Switching - A Two-Stage Decision Process: An Empirical Study of Australian Companies." Thesis, Griffith University, 1996. http://hdl.handle.net/10072/366910.

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This dissertation is concerned with a primary and two secondary research issues. The primary issue pertains to the existence of a two-stage auditor switching decision process; that is the auditor change and the auditor selection stages. The two secondary issues concern the relative influence of variables within their respective decision stages. External auditors are engaged not only to comply with the Corporations Law requirement and Australian Stock Exchange membership conditions but also to reduce the degree of information risk assigned by financial statement users to financial statements prepared by auditee management. The decision to switch auditors may cause financial statement users to assign a higher degree of information risk to financial statements, i.e., the indirect costs of switching auditors. A substantial increase in these indirect costs may have occurred as the average rate that Australian publicly listed companies switch auditor has increased in recent years. However, prior research has provided inconsistent and inconclusive evidence with regard to the variables that influence auditees to switch auditors. To avoid mis-perceptions by financial statement users about the newly appointed auditors' attestation of the financial information prepared by auditees, a greater understanding is needed of the auditor switching decision process to assist in mitigating these indirect costs of switching auditors. In prior research the underlying suggestion why auditees switch auditors is the development of a mis-match of audit services demanded to the services supplied by the incumbent auditor. To overcome this mis-match, auditees after deciding to change auditors then select a specific audit firm that offers suitable services and possesses suitable characteristics. A suggested reason for the inconsistent findings of prior research is that there are two decision stages (auditor change and auditor selection) in the auditor switching decision process and past studies have examined, intentionally or otherwise, different decision stages. From a two decision stage perspective, there are three additional explanations for the inconsistent findings of prior research. These explanations are 1) the inappropriate use of surrogate measures for the decision stage studied, 2) the misuse of the terms auditor change, auditor selection and auditor switching, and 3) the inappropriate research methodology and instrument design employed. This absence of a 'shared agreement' among researchers about the two-stage auditor switching decision concept and misuse of terms may have confused not only researchers but also survey participants and readers of auditor switching literature thus contributing to the inconsistencies in prior evidence as well as perpetuating the inconsistent results where the readers are the future researchers. A review of the literature identified five characteristic variables of the incumbent and replacement audit firms that influence the auditor switching decision. Four variables (disagreements between auditees and auditors that result in, or are caused by, the issuance of a qualified audit report and recommendations from three external sources) in addition to the five incumbent auditor characteristics were found to influence only the auditor change decision. In addition to the five replacement auditor characteristic variables, a further five variables, involving audit firm image creation or other promotional activities, have been found to influence the auditor selection decision stage. A primary and two secondary problems regarding the auditor switching decision process are addressed (1) How and to what extent does the impact of the five auditor characteristics on Australian auditees' decisions to change auditors (to terminate the incumbent auditor's appointment) differ from that on auditees' decisions to select the replacement auditor? (2) How and to what extent are the nine variables used by Australian auditee management in the decision to change auditors (to terminate the incumbent auditors appointment)? (3) How and to what extent are the ten variables used by Australian auditee management in the decision to select a replacement auditor? The provision of evidence to support the two-stage auditor switching decision process may be achieved by jointly examining and identifying significant differences in the perceived influence of auditor characteristics across the two decision stages and a comparison of their rank order of influence within each stage. Three empirical models are constructed to investigate these three research questions. Using the MANOVA (within-subjects) design, the first model is to analyse each respondent's perception of the level of influence of each of the five auditor characteristic variables across the two decision stages. The second and third empirical models are using an one-way ANOVA design to test the influence of each of the respective independent variables (i.e., nine variables for the change decision and ten variables for the selection decision) on the respective dependent variable (i.e., the change decision or the selection decision). Fifty-three usable responses were received from Australian companies identified as voluntarily switching auditors for the reporting year ended 1990 and/or 1991. The data collected for analysis were provided by company executives of these companies. The major findings of this study are: 1) Two of the five auditor characteristics, 'level of audit quality' and 'suitability of non-audit services', differed significantly in their level of relative influence across the two decision stages. Furthermore, there was some support in the results for a perceived difference in the influence of a third auditor characteristic, 'size of audit fees', across both stages. 2) Significant differences were perceived in the level of influence of variables on the auditor change decision stage. The six most influential variables were the higher audit fees, the auditor's offices were not located near the auditee's geographically dispersed offices, the incumbent auditor's lack of industry specialisation, a higher audit quality was not provided, the non-audit services offered were unsuitable, and director's recommendations. 3) In the auditor selection decision stage, significant differences were perceived in the level of influence of variables. The six most influential variables were the lower fees, the recommendations of business colleagues, a higher quality audit can be provided, the suitability of range of non-audit services, the closeness of the auditor's offices to the auditee's geographically dispersed operations, and the availability of industry specialisation. 4) A comparison of the rank order of influence of auditor characteristic variables within each decision stage found variances exist for two variables 'closeness of auditor's offices to the auditee's operations' and 'the level of industry specialisation' across the two stages. 5) The significant difference in the level of influence of characteristics of the incumbent and replacement auditors in the first finding suggests that auditors are not perceived as providing homogeneous services. Furthermore, from the significant difference in these auditor characteristic variables within each decision stage in the second and third findings imply that the auditor characteristics of an auditor are not perceived as homogeneous. The following major conclusions are drawn from this study. The evidence from these major findings support the existence of a two-stage auditor switching decision process. The results also show that auditor switching decision makers' perceptions of the variables that influence auditor switching vary across the two decision stages and with the auditor change and auditor selection decisions. Finally, because the characteristics of the auditors vary in their perceived influence across both stages and within each decision stage, these variances suggest the auditor characteristics supplied are perceived to be heterogeneous. This perceived heterogeneity permits audit firms to differentiate their services offered and requires auditees to employ a two-stage auditor switching decision process.
Thesis (Masters)
Master of Philosophy (MPhil)
Department of Accounting, Finance and Economics
Griffith Business School
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4

Choi, Jin-Young. "Two-stage Semiparametric Estimators for Limited Dependent Variables and its Applications." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:103547.

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Thesis advisor: Arthur Lewbel
This thesis proposes two semiparametric estimators; one for heavily censored panel models and another one for binary-outcome sample selection models. The first chapter proposes a new panel data estimator, and applies it to investigate whether the key assumption underlying most twin studies is valid. Roughly, the assumption is that differences in twins' outcomes can on average be attributed to differences in observed treatments, possibly after conditioning on observable covariates. The empirical results here cast doubt on this assumption, by showing that a particular outcome, survival, varies by birth order, even after conditioning on health-at-birth characteristics. The proposed panel data estimator is the first one in the literature that simultaneously handles having an unknown error distribution, fixed effects, fixed T, fixed censoring point, and heavy (greater than 50%) censoring. These features are all required to adequately deal with the limitations of available census data on twins. The proposed estimator also allows for coefficients that vary by t, and for a censoring point that is an unknown but deterministic function of regressors. The second chapter proposes a new semiparametric estimator for binary-outcome selection models that does not impose any distributional assumption, nor specify the selection equation. The estimator, however, requires a special regressor satisfying a support restriction in the outcome equation and a variable satisfying the exclusion/inclusion restriction; the former should be continuous whereas the latter can be discrete. The estimators of Klein et al. (2011) and Escanciano et al. (2012) require optimization, but our estimator for the outcome equation has a closed-form expression with no need for any optimization (but the selection equation estimation may still need an optimization). We apply MLE and the proposed estimator to US presidential election data in 2008 and 2012 where Barack Obama won to see to what extent racism mattered; we use a prejudice variable as a measure of racism. Putting our empirical findings in advance, there is evidence that the white Democrats voted less for Obama due to prejudice, whereas the white Republicans acted in a more muted fashion (i.e., almost no change in voting due to racism) or voted more for Obama to escape the stigma of racism. We also found evidence of "own-race favor" by blacks
Thesis (PhD) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Economics

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5

Teague, Kory Alan. "Approaches to Joint Base Station Selection and Adaptive Slicing in Virtualized Wireless Networks." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/85966.

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Wireless network virtualization is a promising avenue of research for next-generation 5G cellular networks. This work investigates the problem of selecting base stations to construct virtual networks for a set of service providers, and adaptive slicing of the resources between the service providers to satisfy service provider demands. A two-stage stochastic optimization framework is introduced to solve this problem, and two methods are presented for approximating the stochastic model. The first method uses a sampling approach applied to the deterministic equivalent program of the stochastic model. The second method uses a genetic algorithm for base station selection and adaptively slicing via a single-stage linear optimization problem. A number of scenarios are simulated using a log-normal model designed to emulate demand from real world cellular networks. Simulations indicate that the first approach can provide a reasonably tight solution, but is constrained as the time expense grows exponentially with the number of parameters. The second approach provides a significant improvement in run time with the introduction of marginal error.
Master of Science
5G, the next generation cellular network standard, promises to provide significant improvements over current generation standards. For 5G to be successful, this must be accompanied by similarly significant efficiency improvements. Wireless network virtualization is a promising technology that has been shown to improve the cost efficiency of current generation cellular networks. By abstracting the physical resource—such as cell tower base stations— from the use of the resource, virtual resources are formed. This work investigates the problem of selecting virtual resources (e.g., base stations) to construct virtual wireless networks with minimal cost and slicing the selected resources to individual networks to optimally satisfy individual network demands. This problem is framed in a stochastic optimization framework and two approaches are presented for approximation. The first approach converts the framework into a deterministic equivalent and reduces it to a tractable form. The second approach uses a genetic algorithm to approximate resource selection. Approaches are simulated and evaluated utilizing a demand model constructed to emulate the statistics of an observed real world urban network. Simulations indicate that the first approach can provide a reasonably tight solution with significant time expense, and that the second approach provides a solution in significantly less time with the introduction of marginal error.

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6

Steele, Steven Cory Wyatt. "Optimal Engine Selection and Trajectory Optimization using Genetic Algorithms for Conceptual Design Optimization of Resuable Launch Vehicles." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/51771.

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Proper engine selection for Reusable Launch Vehicles (RLVs) is a key factor in the design of low cost reusable launch systems for routine access to space. RLVs typically use combinations of different types of engines used in sequence over the duration of the flight. Also, in order to properly choose which engines are best for an RLV design concept and mission, the optimal trajectory that maximizes or minimizes the mission objective must be found for that engine configuration. Typically this is done by the designer iteratively choosing engine combinations based on his/her judgment and running each individual combination through a full trajectory optimization to find out how well the engine configuration performed on board the desired RLV design. This thesis presents a new method to reliably predict the optimal engine configuration and optimal trajectory for a fixed design of a conceptual RLV in an automated manner. This method is accomplished using the original code Steele-Flight. This code uses a combination of a Genetic Algorithm (GA) and a Non-Linear Programming (NLP) based trajectory optimizer known as GPOPS II to simultaneously find the optimal engine configuration from a user provided selection pool of engine models and the matching optimal trajectory. This method allows the user to explore a broad range of possible engine configurations that they wouldn't have time to consider and do so in less time than if they attempted to manually select and analyze each possible engine combination. This method was validated in two separate ways. The codes ability to optimize trajectories was compared to the German trajectory optimizer suite known as ASTOS where only minimal differences in the output trajectory were noticed. Afterwards another test was performed to verify the method used by Steele-Flight for engine selection. In this test, Steele-Flight was provided a vehicle model based on the German Saenger TSTO RLV concept and models of turbofans, turbojets, ramjets, scramjets and rockets. Steele-Flight explored the design space through the use of a Genetic Algorithm to find the optimal engine combination to maximize payload. The results output by Steele-Flight were verified by a study in which the designer manually chose the engine combinations one at a time, running each through the trajectory optimization routine to determine the best engine combination. For the most part, these methods yielded the same optimal engine configurations with only minor variation. The code itself provides RLV researchers with a new tool to perform conceptual level engine selection from a gathering of user provided conceptual engine data models and RLV structural designs and trajectory optimization for fixed RLV designs and fixed mission requirement.
Master of Science

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7

Carreras, Máximo [Verfasser], Werner [Akademischer Betreuer] Brannath, Frank [Akademischer Betreuer] Bretz, and Georg [Akademischer Betreuer] Gutjahr. "Two-Stage Adaptive Designs With Interim Treatment Selection / Máximo Ariel Carreras. Gutachter: Frank Bretz ; Georg Gutjahr. Betreuer: Werner Brannath." Bremen : Staats- und Universitätsbibliothek Bremen, 2015. http://d-nb.info/1072746301/34.

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8

Pan, Xi. "THE LABOR MARKET, POLITICAL CAPITAL, AND OWNERSHIP SECTOR IN URBAN CHINA." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/788.

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Over the past three decades, economic reforms have brought about dramatic changes in China. The wave of structural and economic reforms regarding the State-owned Sector (SOS), and the surge of the Non-State-owned Sector (NSOS), have influenced returns in the labor market, such as the returns concerning human capital and political capital in urban China. Presumably, the NSOS would be more marketed-oriented compared to the SOS, and it would have different returns concerning political capital, as represented by Chinese Communist Party (CCP) membership. This is likely because the NSOS would not value Party membership as much as the SOS does. The question of how Party membership is rewarded in the two sectors might also change with the development of the two ownership sectors, as more time passes since the establishment of the economic reforms. I examine whether CCP members display any earnings advantage in these two sectors, and I also explore how such an advantage might have changed over time. Unlike most of the previous studies that have focused on earnings in urban China, I treat Party membership affiliation and ownership sector selection as being endogeneous. I apply the Mlogit -OLS two-stage selection correction estimation proposed by Lee (1983) and discover evidence which suggests that Party membership serves as a proxy for both political and productive skills. A flat Party premium in the SOS and a decreasing Party premium in the NSOS suggest that the Party card served a similar function in the payment scheme present in the SOS during this three year span, whereas the NSOS valued political capital by a decreasing amount over time. The evidence presented in my dissertation indicates that economic reforms tend to mitigate the earning advantage of Party members that occurs as a result of unequal treatment based on Party membership. This evidence suggests that CCP membership is losing its earning power, at least in the NSOS. In addition, the CCP members sacrifice the benefits previously possessed in the adaptation to the transformed economic environment in urban China. However, the rewards to other forms of human capital have increased over time.

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9

Choudhary, Pankaj K. "ASSESSMENT OF AGREEMENT AND SELECTION OF THE BEST INSTRUMENT IN METHOD COMPARISON STUDIES." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1029109764.

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10

Barksten, Martin. "Evaluating the effect of cardinality estimates on two state-of-the-art query optimizer's selection of access method." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189892.

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This master thesis concern relational databases and their query optimizer’s sensitivity to cardinality estimates and the e!ect the quality of the estimate has on the number of different access methods used for the same relation. Two databases are evaluated — PostgreSQL and MariaDB — on a real-world dataset to provide realistic results. The evaluation was done via a tool implemented in Clojure and tests were conducted on a query and subsets of it with varying sample sizes used when estimating cardinality. The results indicate that MariaDB’s query optimizer is less sensitive to cardinality estimates and for all tests select the same access methods, regardless of the quality of the cardinality estimate. This stands in contrast to PostgreSQL’s query optimizer which will vary between using an index or doing a full table scan depending on the estimated cardinality. Finally, it is also found that the predicate value used in the query a!ects the access method used. Both PostgreSQL and MariaDB are found sensitive to this property, with MariaDB having the largest number of di!erent access methods used depending on predicate value.
Detta examensarbete behandlar relationella databaseer och hur stor påverkan kvaliteten på den uppskattade kardinaliteten har på antalet olika metoder som används för att hämta data från samma relation. Två databaser testades — PostgreSQL och MariaDB — på ett verkligt dataset för att ge realistiska resultat. Utvärderingen gjordes med hjälp av ett verktyg implementerat i Clojure och testerna gjordes på en query, och delvarianter av den, med varierande stora sample sizes för kardinalitetsuppskattningen. Resultaten indikerar att MariaDBs query optimizer inte påverkas av kardinalitetsuppskattningen, för alla testerna valde den samma metod för att hämta datan. Detta skiljer sig mot PostgreSQLs query optimizer som varierade mellan att använda sig av index eller göra en full table scan beroende på den uppskattade kardinaliteten. Slutligen pekade även resultaten på att båda databasernas query optimizers varierade metod för att hämta data beroende på värdet i predikatet som användes i queryn.

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11

Kaze, Joshua Taft. "Habitat Selection by Two K-Selected Species: An Application to Bison and Sage Grouse." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4284.

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Population growth for species with long lifespans and low reproductive rates (i.e., K-selected species) is influenced primarily by both survival of adult females and survival of young. Because survival of adults and young is influenced by habitat quality and resource availability, it is important for managers to understand factors that influence habitat selection during the period of reproduction. My thesis contains two chapters addressing this issue for K-selected species in Utah. Chapter one evaluates habitat selection of greater sage-grouse (Centrocercusurophasianus) on Diamond Mountain during the critical nesting and brood-rearing period. Chapter two address selection of birth sites by bison (Bison bison) on Antelope Island, Utah. We collected micro-habitat data for 88 nests and 138 brood locations of greater sage-grouse from 2010-2012 to determine habitat preferences of nesting and brooding sage-grouse. Using random forests modeling techniques, we found that percent sagebrush, percent canopy cover, percent total shrubs, and percent obscurity (Robel pole) best differentiated nest locations from random locations with selection of higher values in each case. We used a 26-day nesting period to determine an average nest survival rate of 0.35 (95% CI = 0.23 – 0.47) for adults and 0.31 (95% CI = 0.14 – 0.50) for juvenile grouse.Brood sites were closer to habitat edges, contained more forbs and less rock than random locations. Average annual adult female survival across the two-year study period was 0.52 (95% CI= 0.38 – 0.65) compared to 0.43 (95% CI= 0.28 – 0.59) for yearlings.Brooding and nesting habitat at use locations on Diamond Mountain met or exceeded published guidelines for everything but forb cover at nest sites. Adult and juvenile survival rates were in line with average values from around the range whereas nest success was on the low end of reported values. For bison, we quantified variables surrounding 35 birth sites and 100 random sites during 2010 and 2011 on Antelope Island State Park. We found females selected birth sites based on landscape attributes such as curvature and elevation, but also distance to anthropogenic features (i.e., human structures such as roads or trails). Models with variables quantifying the surrounding vegetation received no support.Coefficients associated with top models indicated that areas near anthropogenic features had a lower probability of selection as birth sites. Our model predicted 91% of observed birth sites in medium-high or high probability categories. This model of birthing habitat, in cooperation with data of birth timing, provides biologists with a map of high-probability birthing areas and a time of year in which human access to trails or roads could be minimized to reduce conflict between recreation and female bison.

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12

Meyer, Timothy. "A Test of Two-axis Male Mate Choice in Schizocosa Ocreata (Hentz) Based on Experience and Cues Indicating Female State." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1505149313740743.

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13

Wagner, Alec Thomas. "Fundamental Studies of Two Important Atmospheric Oxidants, Ozone and Hydroxyl Radical, Reacting with Model Organic Surfaces." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/45093.

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Heterogeneous reactions between gas-phase oxidants and particulate-phase organic compounds impact many important atmospheric chemical processes. For example, little is known about the reaction dynamics of gaseous oxidants with organic compounds found in the atmosphere. The first step of the reaction between gaseous ozone and solid pentacene was investigated using Reflection Absorption Infrared Spectroscopy (RAIRS). Ozone was found to add to pentacene non-selectively and form a range of products after heavy ozone exposure. The rate limiting step had an activation energy of 17 kJ/mol, which is consistent with the findings of previous ozone oxidation studies for the cleavage of a carbon-carbon double bond. Unfortunately the products could not be used to distinguish between probable reaction mechanisms. Hydroxyl radicals (•OH) play a major role processing atmospheric hydrocarbons. Due to their short lifetimes, not much is known about the dynamics of the first steps of •OH reactions. To investigate these reactions, a rotational state-selector was constructed to filter a molecular beam of •OH for reaction dynamics investigations with organic surfaces. The rotational state-selector was designed to leverage the linear Stark effect to pass only suitable molecules in a particular rotational state and block the flow of any other atoms, molecules and ions in a molecular beam. The state-selector was validated and used to positively deflect molecular beams of methyl iodide and D₂O via the linear Stark effect. Future studies with the rotational state-selector will investigate the initial steps of •OH reactions with solid organic compounds.
Master of Science

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14

Ceddia, Ryan Patrick. "Genomic Characterization of Two Models of Obesity in Mice: Divergent Selection for Epididymal Fat and the Effects of trans-10, cis-12-Conjugated Linoleic Acid." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-08072007-120016/unrestricted/etd.pdf.

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15

LEMECHA, MEGERSA ENDASHAW. "Microcredit and agricultural technology adoptions: evidence from ethiopia." Doctoral thesis, Università Politecnica delle Marche, 2021. http://hdl.handle.net/11566/290144.

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In Etiopia, le donne e le donne capofamiglia rappresentano una quota significativa delle famiglie agricole che sono anche estremamente povere. In questa tesi fornisco prove della necessità di andare oltre il microcredito e promuovere una più ampia inclusione finanziaria per influenzare la maggior parte delle strategie di sussistenza delle famiglie agricole, in particolare le adozioni tecnologiche. Uso un gruppo di famiglie ampio e rappresentativo a livello nazionale ottenuto dall'Etiopia rurale come parte dell'LSMS-ISA della Banca Mondiale a 1) comprendere i vincoli alle adozioni tecnologiche, evidenziando il credito 2) valutare se il microcredito è posizionato a lavorare per la maggior parte di loro. Per effetto di quest'ultimo, esamino le decisioni di partecipare ai mercati del credito e utilizzare un particolare tipo di credito; esplorare il rapporto tra prestatori formali e informali - se servono come sostituti o complementi. Gli ultimi due decenni hanno visto una drammatica espansione dell'accesso fisico al microcredito in ambienti agricoli poveri e rischiosi. Vi è una penetrazione limitata delle banche e molte famiglie, in particolare i piccoli agricoltori e gli agricoltori marginale si affidano a finanziamenti informali. Per molti, il microcredito viene introdotto per salvare i debitori poveri riducendo i vincoli di credito istituzionali e la loro dipendenza dalla finanza informale. Quindi ci si aspetta che la tecnologia dell'informazione e i meccanismi di esecuzione dei contratti dei prestatori di microcredito si trovino tra i due estremi. Mi avvalgo di metodologie econometriche all'avanguardia e complesse che consentono di ottenere risultati più affidabili e, di conseguenza, contributi più specifici alla ricerca e alla pratica.
In Ethiopia, women and female headed households make up significant share of farm households who are also extremely poor. In this thesis I provide evidence for the need to move beyond microcredit and promote a broader financial inclusion to affect a majority of farm households’ livelihood strategies, particularly technology adoptions. I use large and nationally representative panel of households obtained from rural Ethiopia as part of the World Bank’s LSMS-ISA to 1) understand constraints to technology adoptions, highlighting credit 2) assess whether microcredit is positioned to work for a majority of them. To the latter’s effect, I investigate decisions to participate in the credit markets and use a particular credit type; explore the relationship between formal and informal lenders - whether they serve as substitutes or complements. The last two decades has witnessed a dramatic expansion in the physical access to microcredit in poor, risky agrarian settings. There is limited penetration of banks and many households, especially small and marginal farmers rely on informal finance. For many, microcredit is introduced to rescue poor borrowers by reducing institutional credit constraints and their reliance on informal finance. So one expects that the information technology and contract enforcement mechanisms of microcredit lenders to lie between the two extremes. I employ state-of-the-art and complex econometric methodologies which allow to obtain more reliable results and, hence, more specific contributions to research and practice.

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16

Brown, Richard III. "Racial Differences In Juvenile Court Delinquency Outcomes in a Large Urban County in a Midwestern State." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1395403274.

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17

Abdullah, Jiwa. "QoS routing for mobile ad hoc networks using genetic algorithm." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/35198.

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Mobile Ad Hoc Networks (MANETs) are a class of infrastructure less network architecture which are formed by a collection of mobile nodes that communicate with each other using multi-hop wireless links. They eliminate the need for central management, hence each node must operate cooperatively to successfully maintain the network. Each node performs as a source, a sink and a router. Future applications of MANETs are expected to be based on all-IP architecture, carrying a multitude of real-time multimedia applications such as voice, video and data. It would be necessary for MANETs to have an efficient routing and quality of service (QoS) mechanism to support diverse applications. This thesis proposes a set of cooperative protocols that provide support for QoS routing. The first is the on-demand, Non-Disjoint Multiple Routes Discovery protocol (NDMRD). NDMRD allows the establishment of multiple paths with node non-disjoint between source and destination node. It returns to the source a collection of routes with the QoS parameters. The second part of the protocol is the Node State Monitoring protocol for the purpose of monitoring, acquisition, dissemination and accumulation of QoS route information. The third part of the protocol implements the QoS route selection based on a Genetic Algorithm. The GA is implemented online with predetermined initial population and weighted-sum fitness function which operates simultaneously on the node bandwidth, media access delay, end to end delay and the node connectivity index (NCI). The term node connectivity index is a numerical value designed to predict comparatively the longest time a node-pair might be connected wirelessly.

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18

Hamy, Anne-Sophie. "Identification of Factors Predicting Sensitivity or Resistance to Neoadjuvant Chemotherapy in Breast Cancer Neoadjuvant treatment : the future of patients with breast cancer Neoadjuvant treatment for intermediate/high-risk HER2-positive and triple-negative breast cancers: no longer an “option” but an ethical obligation Long-term outcome of the REMAGUS 02 trial, a multicenter randomised phase II trial in locally advanced breast cancer patients treated with neoadjuvant chemotherapy with or without celecoxib or trastuzumab according to HER2 status BIRC5 (survivin) : a pejorative prognostic marker in stage II/III breast cancer with no response to neoadjuvant chemotherapy Beyond Axillary Lymph Node Metastasis, BMI and Menopausal Status Are Prognostic Determinants for Triple-Negative Breast Cancer Treated by Neoadjuvant Chemotherapy Pathological complete response and prognosis after neoadjuvant chemotherapy for HER2-positive breast cancers before and after trastuzumab era: results from a real-life cohort The presence of an in situ component on pre-treatment biopsy is not associated with response to neoadjuvant chemotherapy for breast cancer Chemosensitivity, tumor infiltrating lymphocytes (TILs), and survival of postpartum PABC patients treated by neoadjuvant chemotherapy Lymphovascular invasion after neoadjuvant chemotherapy is strongly associated with poor prognosis in breast carcinoma New insight for pharmacogenomics studies from the transcriptional analysis of two large-scale cancer cell line panels Biological network-driven gene selection identifies a stromal immune module as a key determinant of triple-negative breast carcinoma prognosis A Stromal Immune Module Correlated with the Response to Neoadjuvant Chemotherapy, Prognosis and Lymphocyte Infiltration in HER2-Positive Breast Carcinoma Is Inversely Correlated with Hormonal Pathways Stromal lymphocyte infiltration after neoadjuvant chemotherapy is associated with aggressive residual disease and lower disease-free survival in HER2-positive breast cancer Interaction between molecular subtypes, stromal immune infiltration before and after treatment in breast cancer patients treated with neoadjuvant chemotherapy COX2/PTGS2 Expression Is Predictive of Response to Neoadjuvant Celecoxib in HER2-negative Breast Cancer Patients Celecoxib With Neoadjuvant Chemotherapy for Breast Cancer Might Worsen Outcomes Differentially by COX-2 Expression and ER Status: Exploratory Analysis of the REMAGUS02 Trial Comedications influence immune infiltration and pathological response to neoadjuvant chemotherapy in breast cancer." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS129.

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La chimiothérapie néoadjuvante (CNA) est utilisée dans les cancers du sein agressifs ou localement avancés (CS). Au delà des bénéfices cliniques, elle représente une opportunité pour monitorer in vivo la sensibilité d’une tumeur à un traitement.A partir de l’analyse de sets de données de patients traités par CNA, nous souhaitons identifier des mécanismes associes à la résistance ou sensibilité au traitement. Dans la première partie, nous avons évalué des paramètres, cliniques, anatomopathologiques et transcriptomiques. Nous avons démontré que des éléments non explorés comme la présence d’embols après CNA revêtaient une information pronostique importante. Dans une 2ème partie, nous avons analysé l’impact de l’infiltrat immunitaire dans le cancer du sein, et avons décrit les changements observés entre des échantillons avant et après CNA. Nous avons montré que l’impact pronostique des TILs était différent avant et après CNA, et était opposé dans les CS triple négatif ou HER2-positif. Finalement, nous avons analysé l’impact des comédications pendant la CNA. Nous avons trouvé des effets positifs – via l’augmentation de l’infiltrat immunitaire et la réponse au traitement – et des effets négatifs avec des effets délétères dans certains sous groupes de patients. En conclusion, la situation néoadjuvante représente une plateforme pour générer et potentiellement valider des hypothèses de recherche. La mise à disposition de jeux de données de patients traités par chimiothérapie néoadjuvante constituerait une ressource majeure pour accélérer la recherche contre le cancer du sein
Neoadjuvant chemotherapy (NAC i.e. chemotherapy before surgery) is increasingly being used for aggressive or locally advanced breast cancer (BCs). Beyond clinical benefits, it represents an opportunity to monitor in vivo sensitivity to treatment. Based on the analysis of datasets of BCs patients treated with NAC, we aimed at identifying mechanisms associated with resistance or sensitivity to treatment.In the first part, we evaluated biological, clinical, pathological and transcriptomic patterns. We demonstrated that unexplored pathological features such as post-NAC lymphovascular invasion may carried an important prognostic information.In a second part, we analyzed impact of imune infiltration in BC and we described extensively the changes of tumor infiltrating lymphocytes (TILs) between pre and post-NAC samples. We showed that the prognostic impact of TILs was different before and after NAC, and was opposite in TNBC and HER2-positive BCs. Finally, we investigated the impact of comedications use during NAC. We found both positive effects - while enhancing immune infiltration and response to treatment - and negative effects with deleterisous oncologic outcomes in specific patients subgroups. In conclusion, the neoadjuvant setting represents a platform to both generate and potentially validate research hypotheses aiming at increasing the efficacy of treatment. The public release of real-life datasets of BC patients treated with NAC would represent a major resource to accelerate BC research

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19

Fenollosa, Artés Felip. "Contribució a l'estudi de la impressió 3D per a la fabricació de models per facilitar l'assaig d'operacions quirúrgiques de tumors." Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667421.

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La present tesi doctoral s’ha centrat en el repte d’aconseguir, mitjançant Fabricació Additiva (FA), models per a assaig quirúrgic, sota la premissa que els equips per fer-los haurien de ser accessibles a l’àmbit hospitalari. L’objectiu és facilitar l’extensió de l’ús dels prototips com a eina de preparació d’operacions quirúrgiques, transformant la pràctica mèdica actual de la mateixa manera que en el seu moment ho van fer tecnologies com les que van facilitar l’ús de radiografies. El motiu d’utilitzar FA, en lloc de tecnologies més tradicionals, és la seva capacitat de materialitzar de forma directa les dades digitals obtingudes de l’anatomia del pacient mitjançant sistemes d’escanejat tridimensional, fent possible l’obtenció de models personalitzats. Els resultats es centren en la generació de nou coneixement sobre com aconseguir equipaments d’impressió 3D multimaterials accessibles que permetin l’obtenció de models mimètics respecte als teixits vius. Per facilitar aquesta buscada extensió de la tecnologia, s’ha focalitzat en les tecnologies de codi obert com la Fabricació per Filament Fos (FFF) i similars basades en líquids catalitzables. La recerca s’alinea dins l’activitat de desenvolupament de la FA al CIM UPC, i en aquest àmbit concret amb la col·laboració amb l’Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloc de la tesi inclou la descripció de l’estat de l’art, detallant les tecnologies existents i la seva aplicació a l’entorn mèdic. S’han establert per primer cop unes bases de caracterització dels teixits vius -sobretot tous- per donar suport a la selecció de materials que els puguin mimetitzar en un procés de FA, a efectes de millorar l’experiència d’assaig dels cirurgians. El caràcter rígid dels materials majoritàriament usats en impressió 3D els fa poc útils per simular tumors i altres referències anatòmiques. De forma successiva, es tracten paràmetres com la densitat, la viscoelasticitat, la caracterització dels materials tous a la indústria, l’estudi del mòdul elàstic de teixits tous i vasos, la duresa d’aquests, i requeriments com l’esterilització dels models. El segon bloc comença explorant la impressió 3D mitjançant FFF. Es classifiquen les variants del procés des del punt de vista de la multimaterialitat, essencial per fer models d’assaig quirúrgic, diferenciant entre solucions multibroquet i de barreja al capçal. S’ha inclòs l’estudi de materials (filaments i líquids) que serien més útils per mimetitzar teixits tous. Es constata com en els líquids, en comparació amb els filaments, la complexitat del treball en processos de FA és més elevada, i es determinen formes d’imprimir materials molt tous. Per acabar, s’exposen sis casos reals de col·laboració amb l’HJSD, una selecció d’aquells en els que el doctorand ha intervingut en els darrers anys. L’origen es troba en la dificultat de l’abordatge d’operacions de resecció de tumors infantils com el neuroblastoma, i a la iniciativa del Dr. Lucas Krauel. Finalment, el Bloc 3 té per objecte explorar nombrosos conceptes (fins a 8), activitat completada al llarg dels darrers cinc anys amb el suport dels mitjans del CIM UPC i de l’activitat associada a treballs finals d’estudis d’estudiants de la UPC, arribant-se a materialitzar equipaments experimentals per validar-los. La recerca ampla i sistemàtica al respecte fa que s’estigui més a prop de disposar d’una solució d’impressió 3D multimaterial de sobretaula. Es determina que la millor via de progrés és la de disposar d’una pluralitat de capçals independents a fi de capacitar la impressora 3D per integrar diversos conceptes estudiats, materialitzant-se una possible solució. Cloent la tesi, es planteja com seria un equipament d’impressió 3D per a models d’assaig quirúrgic, a fi de servir de base per a futurs desenvolupaments.
La presente tesis doctoral se ha centrado en el reto de conseguir, mediante Fabricación Aditiva (FA), modelos para ensayo quirúrgico, bajo la premisa que los equipos para obtenerlos tendrían que ser accesibles al ámbito hospitalario. El objetivo es facilitar la extensión del uso de modelos como herramienta de preparación de operaciones quirúrgicas, transformando la práctica médica actual de la misma manera que, en su momento, lo hicieron tecnologías como las que facilitaron el uso de radiografías. El motivo de utilizar FA, en lugar de tecnologías más tradicionales, es su capacidad de materializar de forma directa los datos digitales obtenidos de la anatomía del paciente mediante sistemas de escaneado tridimensional, haciendo posible la obtención de modelos personalizados. Los resultados se centran en la generación de nuevo conocimiento para conseguir equipamientos de impresión 3D multimateriales accesibles que permitan la obtención de modelos miméticos respecto a los tejidos vivos. Para facilitar la buscada extensión de la tecnología, se ha focalizado en las tecnologías de código abierto como la Fabricación por Hilo Fundido (FFF) y similares basadas en líquidos catalizables. Esta investigación se alinea dentro de la actividad de desarrollo de la FA en el CIM UPC, y en este ámbito concreto con la colaboración con el Hospital Sant Joan de Déu de Barcelona (HSJD). El primer bloque de la tesis incluye la descripción del estado del arte, detallando las tecnologías existentes y su aplicación al entorno médico. Se han establecido por primera vez unas bases de caracterización de los tejidos vivos – principalmente blandos – para dar apoyo a la selección de materiales que los puedan mimetizar en un proceso de FA, a efectos de mejorar la experiencia de ensayo de los cirujanos. El carácter rígido de los materiales mayoritariamente usados en impresión 3D los hace poco útiles para simular tumores y otras referencias anatómicas. De forma sucesiva, se tratan parámetros como la densidad, la viscoelasticidad, la caracterización de materiales blandos en la industria, el estudio del módulo elástico de tejidos blandos y vasos, la dureza de los mismos, y requerimientos como la esterilización de los modelos. El segundo bloque empieza explorando la impresión 3D mediante FFF. Se clasifican las variantes del proceso desde el punto de vista de la multimaterialidad, esencial para hacer modelos de ensayo quirúrgico, diferenciando entre soluciones multiboquilla y de mezcla en el cabezal. Se ha incluido el estudio de materiales (filamentos y líquidos) que serían más útiles para mimetizar tejidos blandos. Se constata como en los líquidos, en comparación con los filamentos, la complejidad del trabajo en procesos de FA es más elevada, y se determinan formas de imprimir materiales muy blandos. Para acabar, se exponen seis casos reales de colaboración con el HJSD, una selección de aquellos en los que el doctorando ha intervenido en los últimos años. El origen se encuentra en la dificultad del abordaje de operaciones de resección de tumores infantiles como el neuroblastoma, y en la iniciativa del Dr. Lucas Krauel. Finalmente, el Bloque 3 desarrolla numerosos conceptos (hasta 8), actividad completada a lo largo de los últimos cinco años con el apoyo de los medios del CIM UPC y de la actividad asociada a trabajos finales de estudios de estudiantes de la UPC, llegándose a materializar equipamientos experimentales para validarlos. La investigación amplia y sistemática al respecto hace que se esté más cerca de disponer de una solución de impresión 3D multimaterial de sobremesa. Se determina que la mejor vía de progreso es la de disponer de una pluralidad de cabezales independientes, a fin de capacitar la impresora 3D para integrar diversos conceptos estudiados, materializándose una posible solución. Para cerrar la tesis, se plantea cómo sería un equipamiento de impresión 3D para modelos de ensayo quirúrgico, a fin de servir de base para futuros desarrollos.

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20

Pospíšil, Tomáš. "Vliv provedení zateplení panelového domu v Ostravě na výdaje spojené s jeho provozem." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-402101.

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21

Tsai, Zung-En, and 蔡宗恩. "Two-stage Feature Selection: Mass Detection in Mammograms." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/06396308454936502357.

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碩士
國立成功大學
資訊工程學系碩博士班
93
CAD system of mass detection is commonly composed of four parts: (1) image pre-processing, (2) feature extraction, (3) feature selection and (4) machine learning (detection and classification). For mass detection system, the first demand is high accuracy, and the next one computing time. Two-stage feature selection is therefore proposed to meet this goal of improving the performance of feature selection. 　In the first stage, we would apply two measures, correlation coefficient and information gain, to gather highly correlated features into one cluster, and then choose its representative feature by class separability. After choosing the representative feature, we apply SFS or SFFS to pick up the optimal representative feature set of the first-stage feature selection. In the beginning of the second stage, we first aggregate these optimal representative feature set (including their highly correlated features) together. Next, either SFS or SFFS is iteratively applied to gain the last refined optimal feature set. During the investigation of “two-stage feature selection”, we found that optimal feature set selected at the first stage is almost similar to that selected at the second stage. The correct correlation rate in the 1st stage and 2nd stage are often similar, too. We recognized that “representative feature” can be used to almost respond the behavior of the integrated highly correlated features belonged to the same cluster. Furthermore, we could accelerate the computing time by pruning some specific parts of “two-stage feature selection”. However, the more parts we prune, the worse accuracy we gain. There is a tradeoff between speed and accuracy. Since CAD systems are strictly careful about the accuracy, the action to prune some specific parts of two-stage feature selection must be inspected cautiously.

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22

Lee, Jia-Lun, and 李嘉倫. "Improving the probability of correct selection in two - stage ranking and selection method." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/dtyww7.

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碩士
國立中央大學
工業管理研究所
105
Ranking and selection is a part of Monte Carlo method selecting the best one among the systems. We apply duplicate sampling to reduce the sampling error in statistic, but ranking and selection have same or less observations to achieve the same or higher probability. This method can be divided into two parts, one is the single-stage selection procedure and the other is the two-stage selection procedure. The single-stage method can’t guarantee the correct selection, so that the two-stage selection method is developed. This thesis, based on the two-stage selection proposed by Rinott (1978), is to find out whether the best case can be selected correctly in multiple systems, and this probability is called probability of correct selection. The two-stage selection method is an extension of the single-stage method, as it samples the observations in the first stage, then sample the observations again according to the condition. In practice, the two-stage selection method can achieve probability of correct selection with less observations. Rinott implemented the Slepian inequality to calculate the probability of correct selection lower bound ensuring the probability of correct selection is higher than the confidence level accessing the mode Rinott proposed, Wilcox also provided the constant h, and the table of constant h. In view of these, this thesis is to enhance the probability of correct selection through the two-stage selection method by using the way of multivariate normal cumulative distribution. Under different circumstances, using this approach allows us to get the higher probability than Rinott’s procedure. We also get the higher correct probability with lower constants h. The new table of constant h will be provided to readers as the references, and using some examples to discuss whether the probability of correct selection is improved.

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23

方信雄. "Two-stage Super Slack-based Measure Approach- Shipping Carrier Selection." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/t8k9d8.

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24

Chien, Chien-Yu, and 簡健宇. "Two-Stage Risk Assessment Model by GMDH-based Feature Selection." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/21568328175215189126.

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Анотація:

碩士
國立交通大學
工業工程與管理學系
99
The main revenue of financial institutions comes from the interest they charge to their enterprises customers. But some customers may not be able to pay their debts back, so financial institutions needs to adopt some risk assessment models to measure this credit risk. Many risk assessment models have been developed to deal with the credit risk; most of them used only one stage classifier, but when those methods have to deal with financial data, which was divided into two categories with large numbers of normal instances and small number of default instances, there may be a large gap in accuracy between these two categories. Too many features used in a risk assessment model without feature selection may cause the problem of Overfitting. This study construction a two-stage risk assessment model using Group Method of Data Handling (GMDH) method and decision tree method. In the first stage, this study designs a GMDH-based feature selection method. A feature ranking method is used to rank the entire feature first, and then uses a feature selection method to choose the most appropriate features into construction the GMDH model. In the second stage a decision tree is used to identify the wrong classification instances and revise them into the right ones. In the end two credit risk data in UCI Repository of Machine Learning database and a real case from a Taiwanese financial institution are used to demonstrate the accurate of the proposed two-stage risk assessment model. This study also compares to other references to see that our study would have the same or better result than other models.

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25

Hsu, Yu-Pin, and 許育賓. "Initial Sample Size Selection for the Two-Stage Sampling Procedure." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/14029638421057712690.

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碩士
淡江大學
數學學系碩士班
100
When observations are taken from populations that are normally distributed with unknown and possibly unequal variances, Bishop and Dudewicz (1978) proposed a two-stage sampling procedure for the analysis of variance problem under heteroscedasticity. The procedure is a design-oriented process which requires an initial sample at the first stage and additional observations at the second stage. In this article we discuss the relationship between the initial sample size n_0 and the final total sample size. Two indicators T and R are provided to help selecting the initial sample size.

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26

Lin, Cheng-Feng, and 林正峰. "Using Two-stage Decision Making Techniques in Stocks Portfolio Selection." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/b3bn56.

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Анотація:

碩士
國立臺北科技大學
工業工程與管理研究所
97
In 2008, the financial tsunami caused five major U.S. investment banks of Wall Street to close down or transit. It reveals that inappropriate investments cause deficits. A half of capitalization of global stock market has lost about 30.1 trillion U.S. dollar in 2008. It reveals that the volatile stock market easily makes heavy losses to investors. Therefore, how to invest rationally in the stock market with dangerous financial market is a major problem. It reveals this case of stock portfolio is even more critical for investors. Portfolio is a set which is consisted of more than one asset or security, aimed at risk aversion when investors with limited resources. The most important action about Portfolio is that how to formulate asset allocation. That is, investors how to distribute capital to each asset or security in Portfolio. Therefore, how to decide asset allocation of Portfolio rationally is a goal which must be overcome by this study. Asset allocation of Portfolio is a multiple criteria decision making problem. Decision maker faces much of criteria which conflict for each other, there is no ideal solution could meet all the conditions, but it can be generated a compromise solution according to preferences of decision maker. This study combines the views of "Multiple Objectives Programming" with "Multiple Attribute Decision Making" to form a two-stage model, and then exploit them to generate a rational and objective selection. The results showed that, the obtainable alternative of asset allocation could acquire higher return indeed with acceptable risk.

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27

Lin, Ching-Fen, and 林靜芬. "Application of Two-Stage Stochastic Linear Programming for Portfolio Selection Problem." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/8g3zd5.

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Анотація:

碩士
中原大學
工業工程研究所
93
In this thesis, a portfolio selection problem with closing the portfolio dynamically is considered. The investment strategy is to take the long position on the stocks and the short position in the index futures which starts from the first date when the futures is issued and ends once the revenue exceeds the predetermined threshold which is thought as both fixed and dynamic during the investment period. If the profit is always unable to exceed the threshold during the investment period, all positions will be closed on the maturity date of the futures. To deal with the uncertainty on closing date of the portfolio, it is modeled as a two-stage stochastic linear programming (two-stage SLP). In the first stage of this SLP, a portfolio is obtained under the safety-first criterion; the second stage determines the extra revenue of this given portfolio if it ends during the investment period. The results will be verified by the real-world data and the purpose is to show that the return of the portfolio is steady, profitable and independent of the market. Keywords: Portfolio selection, Futures, Two-stage stochastic linear program.

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28

Ke, Chao-Hsuan, and 柯兆軒. "Two-Stage Gene Selection Algorithms for Classification of Gene Expression Data." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/85395768415812242759.

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Анотація:

碩士
國立高雄應用科技大學
電子與資訊工程研究所碩士班
96
The microarray is a medical diagnostic tool with good efficiency, and it was used for analyzing the behavior characteristic between the gene and disease by the extensive one at present. Microarray data are characterized by a high dimension, which could be analyzed more than thousand of genes and diseases simultaneously. However, it will lead to need more computation time when it is implemented on classification. Many previous literatures showed the feature (gene) selection has some advantage, such as gene extraction which influences classification accuracy effectively, to eliminate the useless genes and improve the calculation performance and classification accuracy. The goal of this study is to select a small set of genes which are useful to the classification task. We proposed a two-stage method using several filter methods to proceed gene ranking and combined the evolutional algorithms on gene expression data to select an optimal gene subset. In this study, an improved particle swarm optimization which introduced a Boolean function was used to improve the disadvantage of standard binary particle swarm optimization as a new evolutional algorithm for gene selection, and both k-nearest neighbor and support vector machine classifiers were used to calculate the classification accuracy. The experimental results revealed that our proposed feature selection method is able to effectively select the relevant gene subset and achieve better classification accuracy than the previous studies.

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29

Chang, Chih-huang, and 張志煌. "A Two-Stage Supplier Selection Approach by DEA and Fuzzy AHP." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/69473744442611640966.

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Анотація:

碩士
國立成功大學
工業與資訊管理學系碩博士班
96
Since the globalization of the supply chain has gradually become an irresistible trend, so the number of appropriate suppliers that a business is required to consider has increased. This means that the selection process has become more detailed and time-and-cost consuming, and thus screening potential suppliers is even more important. In this study, we design a two-stage supplier selection procedure. The first step is to use Data Envelop Analysis (DEA) to select a supplier who has high operating efficiency, and the second stage uses the Fuzzy Analytical Hierarchy Process (FAHP), a multi-attribute decision making method, to rank the potential suppliers both objectively and equitably. Using DEA we can screen the inefficient suppliers and begin the further selection with increased efficiency and ease. Accordingly, the methodology proposed in this article is able to help a business choose suitable suppliers for long-term relationships and increased performance.

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30

Wang, Chien-yuan, and 王健源. "A Two-Stage Approach of Feature Selection on Proteomic Spectra Data." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/51035906383723058330.

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碩士
國立政治大學
統計研究所
94
Early detection and diagnosis can effectively reduce the mortality of cancer. The discovery of biomarkers for the early detection and diagnosis of cancer is thus an important task. In this study, a real proteomic spectra data set of prostate cancer patients and normal patients was analyzed. The data were collected from a Surface-Enhanced Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (SELDI-TOF MS) experiment. The SELDI-TOF MS technology captures protein features in a biological sample. Without suitable pre-processing steps to remove experimental noise, a mass spectrum could consists of more than hundreds or thousands of peaks. To narrow down the search for possible protein biomarkers, only those features that can distinguish between cancer and normal patients are selected. Genetic Algorithm (GA) is a global optimization procedure that uses an analogy of the genetic evolution of biological organisms. It’s shown that GA is effective in searching complex high-dimensional space. In this study, we consider GA-Like algorithm (GAL) for feature selection on proteomic spectra data in classifying prostate cancer patients from normal patients. In addition, we propose two types of Two-Stage GAL algorithm (TSGAL) to improve the GAL.

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31

Lan, Yi-Chia, and 藍翊嘉. "A Two-stage Hybrid Approach for Feature Selection in Microarray Analysis." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/12849556366874025409.

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碩士
國立高雄應用科技大學
電機工程系
97
In cDNA microarray applications, statistical methods and machine learning techniques have been both widely utilized in recent years. Statistical methods are usually used to the analysis, interpretation, explanation and presentation of data of bioinformatics. On the other hand, in some cases machine learning approaches have been used in biomedical applications of complex diseases such as cancer classification. Due to the high-throughput dimensionality nature of microarray data, how to eliminate redundant features of gene and bypass irrelevant samples is becoming an important issue. In order to improve the effectiveness of supervised machine learning approaches for selecting training samples to enhance classification performance, several feature selection and extraction techniques have been developed. The training samples are selected by different feature selection schemes, and which directly impacts the structure of classification models and therefore generates different results. In order to obtain suitable features, in this study we utilized unsupervised machine learning methods for feature selection, which can cluster similar samples into the same group. We incrementally increased the number of groups for population of training samples and then selected suitable features as our experimental dataset from individual groups. In this study, we also applied different methods as the baseline models to compare with our approach for performance evaluation. Furthermore, we examined the different feature selection methods using several classifiers to perform classification tasks, and the experimental result shows that the performance of the developed approach has better than the baseline methods.

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32

Jui-YangHsu and 許瑞洋. "Two-stage individual gene selection methods based on misclassification cost and accuracy." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/16808233634669487228.

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Анотація:

碩士
國立成功大學
資訊管理研究所
98
As the continuous improvement and innovation of bioscience and medical science technologies, scientists developed a series of technologies for gene microarray data to find the relations between diseases and genes. The number of instances in a microar-ray data set is far less than the number of genes in an instances, and lots of genes are irrelevant to a specific disease. Therefore, gene selection is essential to reduce the di-mensionality of a microarray data set. The misclassification costs of different classes are generally different. Previous study performs cost-sensitive gene selection such that the classification accuracy of a microarray data set is greatly reduced. To com-pensate such difficiency, this study considers both misclassification cost and predic-tion accuracy to propose 18 two-stage individual gene selection methods for microar-ray data. The experimental results on eight microarray data sets show that the method adopting probability ranking for misclassification cost in the first stage and t-value ranking for prediction accuracy in the second stage has the best performance evalu-ated by area under cost curve and area under accuracy curve.

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33

Guan-JinWu and 吳冠瑾. "A Study on Two-Stage Customized Bundling with Consideration of Customer Heterogeneity and Self-Selection." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/98658082748955999956.

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Анотація:

碩士
國立成功大學
工業與資訊管理學系
104
The rapid growth of commerce and intense product competition enable firms to use various promotion strategies. Bundling strategies have been extensively used in practice. Firms combine two or more products into a bundle and sell bundles at a discounted price to enhance customers’ willingness to purchase products. This study proposes a two-stage customized bundling model, in which a seller first determines the product categories for bundling and allows consumers to select their products from each category with multiple products based on their preferences. Consumers are allowed to select one main product with the greatest perceived value at the first stage. At the second stage, consumers consider the associations between the main and add-on products and then select the add-in product. This study considers the effects that consumer heterogeneity and different product factors have on the two-stage customized bundling strategy with the aims of maximizing the firm’s profit and consumers’ perceived utility. The obtained results indicate that the customized bundling strategy is beneficial for sellers when the degrees of preferences sensitivity for the main and add-in products are both high. Moreover, the profit of customized bundling strategy is positively correlated with product valuation. This study also analyzes the differences between each strategy and uses numerical examples to investigate the other related factors.

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34

Tsai, Chi-lin, and 蔡奇霖. "Election Prediction Based on Voter Turnout and Voting Choice: A Two-Stage Sample Selection Model." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/09340439629182328761.

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35

LI, JYUN-JHIH, and 李俊志. "Developing A Decision Model of the Supplier Selection by Using Two-Stage House of Quality." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3n4kct.

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Анотація:

碩士
崑山科技大學
資訊管理研究所
106
With the advancement of information technology, global enterprises have the ability to survive in fierce competition, and there are many factors that affect the competitiveness of enterprises. However, supplier selection (SS) is one of the most important decisions. It is difficult to determine the supplier selection criteria (SSC) required for supplier selection. There are many factors that can influence the results of supplier selection, and the customer's voice is the most indispensable in the production process. In the past, most of the enterprises were OEM (original equipment manufacturing) types. However, recently, companies have noticed the importance of the technical level. Therefore, they have switched to the ODM (own designing manufacturing) business model, so whether the technical capabilities can be produced or not. The customer's products have become a new challenge for ODM companies. This study proposes the use of two-stage HOQ for the ODM enterprise type SS model, taking into account customer requirements (CRs), meeting CRs design requirements (DRs), and SSC that can satisfy DRs, providing accurate The SSC carries out SS, the method combines the binary fuzzy semantics, the Defi method, eliminates the information omission caused by subjective consciousness or semantics in the decision-making process, and leads the opinion leader, causing the decision to be affected, and using ELECTRE I and ELECTRE II. Compare the results of the two methods applied to SS through the case, and use the explicit value to carry out the SS model proposed in this study to explore the impact of the missing information on the decision results.

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36

Kao, Min-Che, and 高敏哲. "A Process-Oriented Mechanism by Two-Stage Fuzzy Decision Analysis for Supplier Selection in New Product Development." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/96764800402510538330.

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Анотація:

碩士
明志科技大學
工業工程與管理研究所
102
A company should increase their new product development efficiency to maintain its competitive advantage when product life cycle has been shortening. This may help a company leverage its external suppliers’ technology capabilities when the supplier partners that can meet the company needs are available all over the world, given that the supply chain is following the trend of globalization. However, the development process could thus become very time-consuming because the increased number of available suppliers makes the selection process of suppliers more complex. To deal with this issue, this study proposes a two-stage evaluation structure for selecting new product development suppliers to help a company conduct initial selection of available suppliers and screen out those who are not qualified during the development process, so the complexity of further supplier selection may be reduced. This evaluation structure will first use the DCOR as a basis to construct new product development process that meets a company’s needs. Then, it will apply DSM, DMM, and MDM to analyze the process, organization and components. The analysis results will show the interaction relationship between the organization and the process, the dependent relationship between the organization and components, etc. Along with the supplier’s collaborative capability index, these factors can serve as initial selection criteria for suppliers. Finally, supplier performance index will be applied to these selected suppliers to evaluate the best cooperation partners for the company. Following the steps provided above, a company may conduct the collaborative capability evaluation to select suppliers with excellent interaction capability out of numerous suppliers, so as to shorten the new product development process. Besides, the company may be able to choose correct components from these qualified component suppliers in an appropriate process, so these suppliers can get involved with the early stage of the new product development process and the overall performance of the company can increase.

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37

Huang, Hsing-Wei, and 黃星惟. "The effect of the company''s industry characteristics and management style of corporate governance on the stock returns－the application of Heckman two-stage selection model." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/hkw634.

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Анотація:

碩士
國立臺北科技大學
經營管理系碩士班
102
The purpose of this study is to investigate that the effect between corporate governance and stock returns when the company releases the news. Further, to investigate that which factors would affect corporate governance and cause the different results on the stock returns. Therefore in this study is based on Heckman (1979) the two-stage method to resolve endogeneity of corporate governance, and through the sample selection to examine the relationship between corporate governance and stock returns. This will reduce the traditional model estimation bias, and the past research inconsistencies can be interpreted by the results. Our data is collected from the Taiwan Economic Journal Database (TEJ). The objects of study are all of listed companies in Taiwan, deducting incomplete data, a total of 565 samples. The results of this study can help researchers to understand which factors would affect corporate governance quality, and through it to know corporate governance issues. Not only that, we also can find the existence of sample selection bias. By this study, we want to solve the bias problem by Heckman two-stage method, we also want to provide viable recommended for government decision-making units or reference and improvement

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38

Lo, Cheng-Hsuan, and 羅政炫. "A two-stage decision model for selecting suppliers and distributors." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/94652506036379299646.

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Анотація:

碩士
國立清華大學
工業工程與工程管理學系
93
Nowadays, companies are searching for some ways to improve their competition by more suitable cooperation, more reasonable contract, etc. The concepts to form a supply chain alliance are framed by many companies that want to gain more advantage. The main purpose of forming a supply chain alliance is to lower product cost, to improve quality and to reduce the amount of time to bring the product to the customers. The purpose of this thesis is to build a two-stage decision model for a broker to select his partners on both the strategic level planning and the tactical level planning. The broker acts as an agent or a decision maker or a company with the core competence. The conclusion is that the two-stage model is useful when choosing the partners, and that we can select our partners properly by setting the proper connecting cost for each candidates. Besides, we find out the difference between the two information flows (one-way flow of information and two way flow of information), and the two-way flow takes advantage in the “Connection time” and the ”Response time for order”.

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39

Wang, Te-Gang, and 王德綱. "A Two-Stage Procedure for Selecting Candidate Models in Bayesian Model Averaging for Factorial Design Experiments." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/33867129155652652365.

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40

Das, Priyanka. "Optimal Relay Selection in Interference-Constrained Underlay Cooperative Cognitive Radio." Thesis, 2018. http://etd.iisc.ac.in/handle/2005/4137.

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Cognitive radio (CR) promises to significantly improve the utilization of scarce wireless spectrum. In the underlay mode of CR, which is the focus of the thesis, a secondary user (SU) can simultaneously transmit on the same band as a higher priority primary user (PU) so long as the interference it causes to the PU must be constrained. These interference constraints severely limit the performance of the SUs. Cooperative relaying combined with selection exploits spatial diversity to improve the performance of interference-constrained SUs. In it, one among the available relays is selected for every instantaneous channel power gains of the various links that include the secondary communication links as well as the interference links between the secondary transmitters and the primary receiver. The mapping between the channel power gains and the selected relay is determined by the relay selection (RS) rule employed by the secondary network. Furthermore, it also depends on the interference constraint, which sets underlay CRapart from conventional wireless communications. Although the peak interference constraint is well-studied in the literature on underlay CR, cooperative relaying for the less conservative average interference constraint has not been as thoroughly studied. In this thesis, we focus on developing optimal RS rules that either minimize the average symbol error probability (SEP) or maximize the average rate of the secondary network that is subject to an average interference constraint. We first develop an SEP-optimal RS rule and its two practically implementable variants when the relays are not aware of the instantaneous state of the direct source-to-destination (SD) link. The proposed rules determine which relay to select and whether to select none of the relays at all as a function of the various channel power gains. They outperform several ad hoc RS rules proposed in the literature for underlay CR and generalize the conventional interference-unconstrained RS rule. Next, we present a novel, SD-aware SEP-optimal RS rule for an average interference-constrained underlay CR network. Akey point that the rule highlights -- for the first time -- is that, for the average interference constraint, the signal-to-interference-plus-noise-ratio (SINR) ofthe direct SD link affects the choice of the optimal relay. Furthermore, as the SINR increases, the odds that no relay transmits increase. We also propose a low feedback and near-optimal variant of the SD-aware SEP-optimal RS rule that requires just one bit of feedback about the state of the direct SD link to the relays. Compared to the SD-unaware RS rules, these rules markedly reduce the SEP by up to two orders of magnitude.We then analyze the average SEPs and diversity order of the proposed RS rules to quantify their performance. Thereafter, we propose a rate-optimal RS rule that maximizes the fading-averaged transmission rate of an average interference-constrained underlay CR network. It differs functionally from the several ad hoc incremental relaying schemes proposed in the literature, but requires a feedback overhead that is comparable to them. We then analyze the average rate of the secondary network for this RS rule. We gain several insights by studying the asymptotic regimes of low and high average SINRs. Lastly, we study a practically-motivated channel state information (CSI) model for an underlay CR network with multiple primary receivers, in which the channel gains of only a subset of the interference links are available at the source and relays. Moreover, this available CSI is imperfect due to channel estimation error. Based on such incomplete and imperfect CSI, the source and relays back-off their transmit powers in order to satisfy an interference outage constraint. We derive the outage probability and average rate of the secondary network for the rate-optimal RS rule. An interesting observation that comes out of our study is that full diversity order is still achievable even with such incomplete and imperfect CSI.

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41

Holubová, Markéta. "Změna třídního klimatu po odchodu žáků na osmiletá gymnázia." Doctoral thesis, 2018. http://www.nusl.cz/ntk/nusl-379250.

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The aim of the dissertation is to compare the psychosocial climate of the classes between the 5th and 6th grades of Czech elementary school. In the train of pupils' leaving into the high- tracked schools there are significant organizational changes in the classes of the 6th grade. This theme includes the phenomenon of the early tracking, when some pupils can leave the mainstream of education (elementary school) and start attending the high-tracked schools (multi-year gymnasium). The aim of our study is to contribute to the research, that with the departure of students into high-tracked schools the psychosocial climate in the classes of the 6th grade unequivocally exacerbates. We are also interested in which specific students are accepted into high-tracked schools, and whether they are effective classroom leaders and socio- metric stars. In our study, we also find out the classroom positions of students who are continuously educated in the 5th and 6th grades of the elementary schools and their classmates, who have come as new students into the classes of the 6th grade. In the theoretical section we introduce the foreign and domestic researches which were conducted on the association between tracking and classroom climate. The empirical part inquiries into a detailed analysis of quantitative research...

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