Tesi: "Statistics"

1

Tauber, Vojtěch. "Vývoj právní úpravy postavení a organizace statistické služby v Československu 1918 - 1938". Master's thesis, Vysoká škola ekonomická v Praze, 2015. http://www.nusl.cz/ntk/nusl-201593.

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This diploma thesis examines the legislation of the status and organisation of the statistical service in Czechoslovakia in the years 1918-1938 which has lacked sufficient exploration. In this period, statistics referring to public administration was centralised and under the responsibility of the State Statistical Council and the State Statistical Office. These institutions are given special attention, particularly issues associated with their intricate aspects: personnel, budget and location. While the State Statistical Office was one of the central government authorities in Czechoslovakia, the State Statistical Council had the nature of an advisory body and an independent decision-making authority. The centralisation did not apply to statistical surveys carried out by certain cities. This thesis uses primarily unpublished archive materials and published sources concerning the activities of the State Statistical Office and the State Statistical Council.

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Kazlauskienė, Aušra. "Pradinių klasių mokinių statistinių gebėjimų ugdymas". Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050902_110922-16508.

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The problem of the research is systematic approach and accessibility of the content of developing statistical skills for primary school pupils. The content of developing elements of statistical skills and probability theory integrates pupils’ mathematical skills, knowledge of the content of other subjects, general skills of cognition and their personal experience, therefore it is a general problem of primary education; A system of items intended for teaching elements of statistics and probability theory is valid and accessible for pupils provided it covers: - technical skills of statistics (an ability to read and represent data); - skills of mathematical operations (to calculate the mean, classify data, round off numbers, grasp elements of probability theory, determine percentage of a number); - cognitive skills of the level accessible to pupils (ability to word a problem, define a hypothesis, compile data to verify the hypothesis, analyse and interpret data, draw conclusions). The premises for successful development of primary school pupils’ statistical skills are as follows: - development of primary school teachers’ statistical skills in the framework of their academic and continued education; - establishment of the content of developing statistical skills corresponding to international standards in the general curricula of the primary school; - provision of teaching statistics and probability theory elements based in the skills acquired in the primary school in the... [to full text]

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3

Holmberg, Anders. "Essays on Model Assisted Survey Planning". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3417.

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4

Marohn, Frank [Verfasser]. "On statistical information of extreme order statistics / Frank Marohn". Würzburg : Universität Würzburg, 2010. http://d-nb.info/1101947373/34.

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5

Wiberg, Marie H. "Computerized achievement tests : sequential and fixed length tests". Doctoral thesis, Umeå universitet, Statistiska institutionen, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-148.

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The aim of this dissertation is to describe how a computerized achivement test can be constructed and used in practice. Throughout this dissertation the focus is on classifying the examinees into masters and non-masters depending on their ability. However, there has been no attempt to estimate their ability. In paper I, a criterion-referenced computerized test with a fixed number of items is expressed as a statistical inference problem. The theory of optimal design is used to find the test that has the strongest power. A formal proof is provided showing that all items should have the same item characteristics, viz. high discrimination, low guessing and difficulty near the cutoff score, in order to give us the most powerful statistical test. An efficiency study shows how many times more non-optimal items are needed if we do not use optimal items in order to achieve the same power in the test. In paper II, a computerized mastery sequential test is examined using sequential analysis. The focus is on examining the sequential probability ratio test and to minimize the number of items in a test, i.e. to minimize the average sample number function, abbreviated as the ASN function. Conditions under which the ASN function decreases are examined. Further, it is shown that the optimal values are the same for item discrimination and item guessing, but differ for item difficulty compared with tests with fixed number of items. Paper III presents three simulation studies of sequential computerized mastery tests. Three cases are considered, viz. the examinees' responses are either identically distributed, not identically distributed, or not identically distributed together with estimation errors in the item characteristics. The simulations indicate that the observed results from the operating characteristic function differ significantly from the theoretical results. The mean number of items in a test, the distribution of test length and the variance depend on whether the true values of the item characteristics are known and whether they are iid or not. In paper IV computerized tests with both pretested items with known item parameters, and try-out items with unknown item parameters are considered. The aim is to study how the item parameters for try-out items can be estimated in a computerized test. Although the unknown examinees' abilities may act as nuisance parameters, the asymptotic variance of the item parameter estimators can be calculated. Examples show that a more reliable variance estimator yields much larger estimates of the variance than commonly used variance estimators.

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Obryant, Monique J. "How Attitudes towards Statistics Courses and the Field of Statistics Predicts Statistics Anxiety among Undergraduate Social Science Majors: A Validation of the Statistical Anxiety Scale". Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011855/.

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The aim of this study was to validate an instrument that can be used by instructors or social scientist who are interested in evaluating statistics anxiety. The psychometric properties of the English version of the Statistical Anxiety Scale (SAS) was examined through a confirmatory factor analysis of scores from a sample of 323 undergraduate social science majors enrolled in colleges and universities in the United States. In previous studies, the psychometric properties of the Spanish and Italian versions of the SAS were validated; however, the English version of the SAS had never been assessed. Inconsistent with previous studies, scores on the English version of the SAS did not produce psychometrically acceptable values of validity. However, the results of this study suggested the potential value of a revised two-factor model SAS to measure statistics anxiety. Additionally, the Attitudes Towards Statistics (ATS) scale was used to examine the convergent and discriminant validities of the two-factor SAS. As expected, the correlation between the two factors of the SAS and the two factors of the ATS uncovered a moderately negative correlation between examination anxiety and attitudes towards the course. Additionally, the results of a structural regression model of attitudes towards statistics as a predictor of statistics anxiety suggested that attitudes towards the course and attitudes towards the field of statistics moderately predicts examination anxiety with attitudes towards the course having the greatest influence. It is recommended that future studies examine the relationship between attitudes towards statistics, statistics anxiety, and other variables such as academic achievement and instructional style.

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Hardy, James C. (James Clifford). "A Monte Carlo Study of the Robustness and Power Associated with Selected Tests of Variance Equality when Distributions are Non-Normal and Dissimilar in Form". Thesis, University of North Texas, 1990. https://digital.library.unt.edu/ark:/67531/metadc332130/.

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When selecting a method for testing variance equality, a researcher should select a method which is robust to distribution non-normality and dissimilarity. The method should also possess sufficient power to ascertain departures from the equal variance hypothesis. This Monte Carlo study examined the robustness and power of five tests of variance equality under specific conditions. The tests examined included one procedure proposed by O'Brien (1978), two by O'Brien (1979), and two by Conover, Johnson, and Johnson (1981). Specific conditions included assorted combinations of the following factors: k=2 and k=3 groups, normal and non-normal distributional forms, similar and dissimilar distributional forms, and equal and unequal sample sizes. Under the k=2 group condition, a total of 180 combinations were examined. A total of 54 combinations were examined under the k=3 group condition. The Type I error rates and statistical power estimates were based upon 1000 replications in each combination examined. Results of this study suggest that when sample sizes are relatively large, all five procedures are robust to distribution non-normality and dissimilarity, as well as being sufficiently powerful.

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8

Johnson, Eric P. "Composite strength statistics from fiber strength statistics". Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/26420.

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Utilization of composites in critical design applications requires an extensive engineering experience data base which is generally lacking, especially for rapidly developing constituent fibers. As a supplement, an accurate reliability theory can be applied in design. This investigation is a part of a research effort to develop a probabilistic model of composite reliability capable of using data produced in small laboratory test samples to predict the behavior of large structures with respect to their actual dimensions. This work included testing of composite strength which was then used in exploring the methodology of predicting composite reliability from the parent single filament fiber strength statistics. This required testing of a coordinate set of test samples which consisted of a composite and its parent fibers. Previously collected fiber strength statistics from two different production spools were used in conjunction with the current effort. This investigation established that, for a well made composite, the Local Load Sharing Model of reliability prediction exhibited outstanding correlation with experimental data and was sufficiently sensitive to predict deficient composite strength due to a specific fiber spool with an abnormally weak lower tail. In addition, it provided an upper bound on the composite reliability. This investigation is unique in that is used a coordinate set of data with an unambiguous genesis of parent fiber and subsequent composite. The findings of this investigation are also definitive in that six orders of extrapolation of size in reliability prediction has been verified

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9

Lee, Yun-Soo. "On some aspects of distribution theory and statistical inference involving order statistics". Virtual Press, 1991. http://liblink.bsu.edu/uhtbin/catkey/834141.

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Statistical methods based on nonparametric and distribution-free procedures require the use of order statistics. Order statistics are also used in many parametric estimation and testing problems. With the introduction of modern high speed computers, order statistics have gained more importance in recent years in statistical inference - the main reason being that ranking a large number of observations manually was difficult and time consuming in the past, which is no longer the case at present because of the availability of high speed computers. Also, applications of order statistics require in many cases the use of numerical tables and computer is needed to construct these tables.In this thesis, some basic concepts and results involving order statistics are provided. Typically, application of the Theory of Permanents in the distribution of order statistics are discussed. Further, the correlation coefficient between the smallest observation (Y1) and the largest observation (Y,,) of a random sample of size n from two gamma populations, where (n-1) observations of the sample are from one population and the remaining observation is from the other population, is presented.
Department of Mathematical Sciences

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10

Kim, Woosuk. "Statistical Inference on Dual Generalized Order Statistics for Burr Type III Distribution". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1396533232.

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11

Carlqvist, Håkan. "Multiscale analysis of multi-channel signals". Doctoral thesis, KTH, Matematik (Avd.), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230.

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I: Amplitude and phase relationship between alpha and beta oscillations in the human EEG We have studied the relation between two oscillatory patterns within EEG signals (oscillations with main frequency 10 Hz and 20 Hz), with wavelet-based methods. For better comparison, a variant of the continuous wavelet transform, was derived. As a conclusion, the two patterns were closely related and 70-90 % of the activity in the 20 Hz pattern could be seen as a resonance phenomenon of the 10 Hz activity. II: A local discriminant basis algorithm using wavelet packets for discrimination between classes of multidimensional signals We have improved and extended the local discriminant basis algorithm for application on multidimensional signals appearing from multichannels. The improvements includes principal-component analysis and crossvalidation- leave-one out. The method is furthermore applied on two classes of EEG signals, one group of control subjects and one group of subjects with type I diabetes. There was a clear discrimination between the two groups. The discrimination follows known differences in the EEG between the two groups of subjects. III: Improved classification of multidimensional signals using orthogonality properties of a time-frequency library We further improve and refine the method in paper2 and apply it on 4 classes of EEG signals from subjects differing in age and/or sex, which are known factors of EEG alterations. As a method for deciding the best basis we derive an orthogonalbasis- pursuit-like algorithm which works statistically better (Tukey's test for simultaneous confidence intervals) than the basis selection method in the original local discriminant basis algorithm. Other methods included were Fisher's class separability, partial-least-squares and cross-validation-leave-one-subject out. The two groups of younger subjects were almost fully discriminated between each other and to the other groups, while the older subjects were harder to discriminate.
QC 20101001

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12

Gustavsson, André. "Elpriserna på den nordiska elbörsen : Prognosmodellering med hjälp av ARIMA-modeller". Thesis, Umeå University, Department of Statistics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34820.

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13

Johansson, Mikael, e Erik Jönsson. "Evaluating a cumulative voting process : An analysis of different approaches". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34822.

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14

Wennberg, Jessica. "Möjligheternas kommun? : En analys av den framtida bostadsförsörjningen i Pajala Kommun". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34823.

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15

Gustavsson, André. "Prognossäkerhet : Tillför en heteroskedastisk modell någon säkerhet hos Box och Jenkins prognosmodeller?" Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34825.

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16

Lindmark, Anita. "Reliabilitet hos metoder för mätning av avstånd mellan sekvenser : En simuleringsstudie i R-paketet TraMineR". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34826.

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17

Andersdotter, Persson Anna. "Kalibrering som ett sätt att hantera bortfall : Vilken korrelation krävs mellan hjälp- och responsvariabler?" Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34827.

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18

Andersson, Björn. "Consequences of near-unfaithfulness in a finite sample : a simulation study". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34828.

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19

Hägg, David, e Henrik Olsson. "Komorbida sjukdomar hos individer med svår psoriasis : En analys med logistiska och loglinjära modeller". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34829.

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Lindberg, Fredrik. "Den demografiska utvecklingen i dagens Sverige : Konsekvenser för den framtida försörjningsbördan". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34830.

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21

Boberg, Lina. "Fertilitet och mortalitet i 1700- och 1800-talets Skellefteå : En modelleringsstudie". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34831.

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Ferm, Martin. "Prediktering av skogliga variabler med data från flygburen laser : En jämförelse mellan multipla regressionsmodeller och k nearest neighbour-modeller". Thesis, Umeå University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-34833.

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Kang, Jian. "Analysis of Temperature and Carbon Dioxide Based on Ice Core Data". Thesis, Uppsala University, Department of Statistics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-126771.

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It is widely considered that the raise of carbon dioxide is a main causeof global warming, but nature scientific has not provided us the completeand precise causes of this phenomenon. We would like to analyze whetherthere exists long-term causality between temperature and carbon dioxidewith the Vostok Ice-Core data from 400,000 years ago to 6,000 years ago.According to the properties of data, intervention analysis and time seriesanalysis with exponential time trend are applied as the methods of univariateanalysis, so that we can fit the deterministic time trends of data,and we select the time series model with exponential time trend as the finalmodel of univariate analysis by comparison. With the idea of Perron in1989, we consider determining the structural break points based on the natureof data, in order to find the best model. Then using a bivariate systemto analyze both temperature and carbon dioxide simultaneously will bereasonable, and the Granger-Causality test is an appropriate one to judgethe forecasting relation between these two series. Finally, the null hypothesisof the test, that carbon dioxide does not Granger-cause temperature,should be rejected, and this is a one way relation. Thus, this article canprovide strong empirical evidence to show that carbon dioxide causes thechange of temperature.

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Ekström, Joakim. "Contributions to the Theory of Measures of Association for Ordinal Variables". Doctoral thesis, Uppsala universitet, Statistik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-100735.

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In this thesis, we consider measures of association for ordinal variables from a theoretical perspective. In particular, we study the phi-coefficient, the tetrachoric correlation coefficient and the polychoric correlation coefficient. We also introduce a new measure of association for ordinal variables, the empirical polychoric correlation coefficient, which has better theoretical properties than the polychoric correlation coefficient, including greatly enhanced robustness. In the first article, entitled ``On the relation between the phi-coefficient and the tetrachoric correlation coefficient'', we show that under given marginal probabilities there exists a continuous bijection between the two measures of association. Furthermore, we show that the bijection has a fixed point at zero for all marginal probabilities. Consequently, the choice of which of these measures of association to use is for all practical purposes a matter of preference only. In the second article, entitled ``A generalized definition of the tetrachoric correlation coefficient'', we generalize the tetrachoric correlation coefficient so that a large class of parametric families of bivariate distributions can be assumed as underlying distributions. We also provide a necessary and sufficient condition for the generalized tetrachoric correlation coefficient to be well defined for a given parametric family of bivariate distributions. With examples, we illustrate the effects on the polychoric correlation coefficient of different distributional assumptions. In the third article, entitled ``A generalized definition of the polychoric correlation coefficient'', we generalize the polychoric correlation coefficient to a large class of parametric families of bivariate distributions, and show that the generalized and the conventional polychoric correlation coefficients agree on the family of bivariate normal distributions. With examples, we illustrate the effects of different distributional assumptions on the polychoric correlation coefficient. In combination with goodness-of-fit p-values, the association analysis can be enriched with a consideration of possible tail dependence. In the fourth article, we propose a new measure of association for ordinal variables, named the empirical polychoric correlation coefficient. The empirical polychoric correlation coefficient relaxes the fundamental assumption of the polychoric correlation coefficient so that an underlying joint distribution is only assumed to exist, not to be of a particular parametric family. We also provide an asymptotical result, by which the empirical polychoric correlation coefficient converges almost surely to the true polychoric correlation under very general conditions. Thus, the proposed empirical polychoric correlation coefficient has better theoretical properties than the polychoric correlation coefficient.

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Rota, Bernardo Joao. "USING FINITE MIXTURE OF MULTIVARIATE POISSON FOR DETECTION OF MEASUREMENT ERRORS IN COUNT DATA". Thesis, Örebro universitet, Handelshögskolan vid Örebro universitet, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-12562.

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Sahl, Åsa. "Age Cohort Effects on Measles, Mumps and Rubella Seroimmunity in Swedish Childbearing Women". Thesis, Örebro universitet, Handelshögskolan vid Örebro universitet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-15785.

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Lundell, Love, e Victor Ståhl. "Transferfunktionsmodeller modellering och prognoser av Sjötransportindex". Thesis, Örebro universitet, Handelshögskolan vid Örebro universitet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-15908.

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We have by Statistics Sweden (SCB) been given the task of using different dynamic regression models in order to forecast service price index for sea transport. The aim is to see whether these models provide better forecasts than those previously used. This essay aim to identify, estimate and evaluate the selected prediction models. Through our data material we were given access to 28 sightings of sea transport index during the period of 2004 q1 to 2010 q4. We have chosen to evaluate three different transfer function models, one ARIMA model and one naive forecasting model. The input variables we decided to test in our transfer function models were the price of petroleum products, the port activity in Swedish ports and the lending rate of Swedish Central bank. The results of our study suggest that transfer function models generally provide better models than the ARIMA model and the naive forecast model. Results also show that both the transfer function models and ARIMA model seem to provide better models than the naïve forecasting model. The transfer function model that gave the lowest forecasting errors had interest rate as an input variable.

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Petric, Milica. "ON THE EFFECTS OF THE FOLLOW-UP IN THE STATISTICS SWEDEN SURVEY OF HOUSEHOLD FINANCES". Thesis, Örebro universitet, Handelshögskolan vid Örebro universitet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-16540.

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Strömberg, Karolin. "En jämförande studie av konsumentgruppers värderingar av miljö- och ursprungsmärkning avmatfisk". Thesis, Örebro universitet, Handelshögskolan vid Örebro universitet, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-17183.

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Whitehead, Andile. "Statistical-thermodynamical analysis, using Tsallis statistics, in high energy physics". Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13391.

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Includes bibliographical references.
Obtained via the maximisation of a modified entropy, the Tsallis distribution has been used to fit the transverse momentum distributions of identified particles from several high energy experiments. We propose a form of the distribution described in Cleymans and Worku, 2012, and show it to be thermodynamically consistent. Transverse momenta distributions and fits from ALICE, ATLAS, and CMS using both Tsallis and Boltzmann distributions are presented.

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Strnadová, Lenka. "Statistika a její využití (zneužití) při tvorbě informací". Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-194698.

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This diploma thesis is focused on how statistics and statistical concepts can be abused to influence a public opinion. The thesis includes theoretical knowledge regarding to statistics, public opinion and institutions which are commonly used as a source of statistical data. A questionnaire was used for a practical part of the diploma thesis. The questionnaire should answer research questions included in the introduction. MS Excel and SAS EG 5.1 were used to process a questionnaire data. There was chosen one or several examples of use and abuse of statistics in creation of information for influencing public opinion almost in all chapters. The conclusion contains a summary of all findings and answers to research questions defined in the introduction of the diploma thesis.

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Frey, Jesse C. "Inference procedures based on order statistics". Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1122565389.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xi, 148 p.; also includes graphics. Includes bibliographical references (p. 146-148). Available online via OhioLINK's ETD Center

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Thulin, Måns. "On two classic problems in statistics". Licentiate thesis, Uppsala universitet, Matematisk statistik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-171962.

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Vaitkevičius, Robertas. "Duomenų kompiuterinės statistinės analizės technologijos". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080929_140053-98826.

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Darbo „Duomenų kompiuterinės statistinės analizės technologijos“ tikslas – išanalizuoti ir palyginti įvairių populiarių statistinių paketų galimybes bei pateikti rekomendacijas vartotojui. Šiame darbe buvo išanalizuoti SPSS 8.0 for Windows, STATISTICA 7 ir Minitab 15 English statistiniai paketai. Atlikti statistiniai skaičiavimai su anketos „Apie tai, kaip tu gyveni“ duomenimis, panaudojant minėtus statistinius paketus. Įvertintos šių statistinių paketų galimybės. Sudarytos statistinių paketų lyginamosios analizės lentelės. Pateiktos rekomendacijos vartotojui, padedančios jam pagrįstai pasirinkti tinkamiausią statistinį paketą, atsižvelgiant į vartotojo poreikius ir galimybes. Statistiniam paketui STATISTICA 7 sukurtos dvi makrokomandos, panaudojant šiame pakete integruotą VISUAL BASIC programavimo kalbą. Pirmoji makrokomanda skaičiuoja tiriamųjų anketų užpildymo baigtumo laipsnius. Antroji makrokomanda filtruoja pasirinkto kintamojo duomenis pagal pasirinktą kriterijų. Darbas inovatyvus tuo, kad sukurtos dvi makrokomandos, praplečiančios statistinio paketo STATISTICA 7 galimybes.
The aim of work “The technologies of computer-based statistical analysis of data”- to analyse and to compare the potentials of various popular statistical packages and to propose the recommendations for the consumer. In this work there were analysed SPSS 8.0 For Windows, STATISTICA 7 and Minitab 15 English statistical packages. Using these mentioned packages there were accomplished statistical calculations according to the questionnaire “About that, how do you live” data. There were assessed the potentials of these statistical packages. There were composed the charts of comparative analysis of the statistical packages. Recommendations were given for the consumer, helping him to pick reasonably the best statistical package, considering consumer’s requirements and possibilities. For the statistical package STATISTICA 7 there were created two macros, using VISUAL BASIC computerese integrated in this package. The first macro calculates the completeness degrees of the investigative questionnaires filling. The second macro filters the data of chosen variable according to the chosen criterion. This work is innovative that there were created two macros, extending potentials of statistical package STATISTICA 7.

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Slob, Wout. "Strategies in applying statistics in ecological research /". Amsterdam : Free University Press, 1986. http://bibpurl.oclc.org/web/28544.

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Wang, Baoyong. "Fractionation Statistics". Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31001.

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Paralog reduction, the loss of duplicate genes after whole genome duplication (WGD) is a pervasive process. Whether this loss proceeds gene by gene or through deletion of multi-gene DNA segments is controversial, as is the question of fractionation bias, namely whether one homeologous chromosome is more vulnerable to gene deletion than the other. As a null hypothesis, we first assume deletion events, on one homeolog only, excise a geometrically distributed number of genes with unknown mean mu, and these events combine to produce deleted runs of length l, distributed approximately as a negative binomial with unknown parameter r; itself a random variable with distribution pi(.). A biologically more realistic model requires deletion events on both homeologs distributed as a truncated geometric. We simulate the distribution of run lengths l in both models, as well as the underlying pi(r), as a function of mu, and show how sampling l allows us to estimate mu. We apply this to data on a total of 15 genomes descended from 6 distinct WGD events and show how to correct the bias towards shorter runs caused by genome rearrangements. Because of the difficulty in deriving pi(.) analytically, we develop a deterministic recurrence to calculate each pi(r) as a function of mu and the proportion of unreduced paralog pairs. This is based on a computing formula containing nested sums. The parameter mu can be estimated based on run lengths of single-copy regions. We then reduce the computing formulae, at least in the one-sided case, to closed form. This virtually eliminates computing time due to highly nested summations. We formulate a continuous version of the fractionation process, deleting line segments of exponentially distributed lengths in analogy to geometric distributed numbers of genes. We derive nested integrals and discover that the number of previously deleted regions to be skipped by a new deletion event is exactly geometrically distributed. We undertook a large simulation experiment to show how to discriminate between the gene-by-gene duplicate deletion model and the deletion of a geometrically distributed number of genes. This revealed the importance of the effects of genome size N, the mean of the geometric distribution, the progress towards completion of the fractionation process, and whether the data are based on runs of deleted genes or undeleted genes.

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37

Chou, Chihong. "Fractional statistics". Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/31030.

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38

Chiarella, Andrew. "Statistical reasoning and scientific inquiry : statistics in the physical science classroom". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33882.

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Teaching science using an inquiry approach is encouraged by several organisations responsible for defining teaching and learning guidelines in North America. However, using this approach can be difficult because of the complexity of inquiry. One source of difficulty is an inability to make sense of the data. Error variation, in particular, poses a significant barrier to the correct interpretation of data and therefore successful inquiry learning. A study was conducted to examine middle school students' ability to make sense of the data they collected in three related experiments. These data involved taking measurements of two continuous variables that were affected by error variation. The results indicated that students tended not to use abstract patterns to describe the data but rather used more local patterns that did not make use of the whole data set. However, many students also indicated an intuitive understanding that a greater amount of data could be used to generate results that are more accurate. This suggests a disparity between what the students understand about data and what they are capable of doing with data. Educational implications are that students may benefit from learning ideal patterns that can be compared to non-ideal data they collect.

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Raj, Alvin Andrew. "Ambiguous statistics - how a statistical encoding in the periphery affects perception". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79214.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2013.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 159-163).
Recent understanding in human vision suggests that the periphery compresses visual information to a set of summary statistics. Some visual information is robust to this lossy compression, but others, like spatial location and phase are not perfectly represented, leading to ambiguous interpretations. Using the statistical encoding, we can visualize the information available in the periphery to gain intuitions about human performance in visual tasks, which have implications for user interface design, or more generally, whether the periphery encodes sufficient information to perform a task without additional eye movements. The periphery is most of the visual field. If it undergoes these losses of information, then our perception and ability to perform tasks efficiently are affected. We show that the statistical encoding explains human performance in classic visual search experiments. Based on the statistical understanding, we also propose a quantitative model that can estimate the average number of fixations humans would need to find a target in a search display. Further, we show that the ambiguities in the peripheral representation predict many aspects of some illusions. In particular, the model correctly predicts how polarity and width affects the Pinna-Gregory illusion. Visualizing the statistical representation of the illusion shows that many qualitative aspects of the illusion are captured by the statistical ambiguities. We also investigate a phenomena known as Object Substitution Masking (OSM), where the identity of an object is impaired when a sparse, non-overlapping, and temporally trailing mask surrounds that object. We find that different types of grouping of object and mask produce different levels of impairment. This contradicts a theory about OSM which predicts that grouping should always increase masking strength. We speculate some reasons for why the statistical model of the periphery may explain OSM.
by Alvin Andrew Raj.
Ph.D.

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40

Schneider, William Ray. "The Relationship Between Statistics Self-Efficacy, Statistics Anxiety, and Performance in an Introductory Graduate Statistics Course". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3335.

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The purpose of this study was to determine the relationship between statistics self-efficacy, statistics anxiety, and performance in introductory graduate statistics courses. The study design compared two statistics self-efficacy measures developed by Finney and Schraw (2003), a statistics anxiety measure developed by Cruise and Wilkins (1980), and a course performance measure. To view self-efficacy from two perspectives, the Current Statistics Self-Efficacy (CSSE) assessed student confidence in their ability to complete specific statistics tasks in the present, whereas Self-Efficacy to Learn Statistics (SELS) assessed student confidence in their ability to learn statistics in the future. The performance measure was the combined average of the midterm and final exam scores only, excluding grades from other course activities. The instruments were distributed to four sections of an introductory graduate statistics course (N=88) in a College of Education at a large metropolitan university during the first week of the semester during Fall 2009 and Spring 2010. Both of the statistics self-efficacy measures revealed a low to moderate inverse relationship with statistics anxiety and a low to moderate direct relationship with each other. In this study there was no correlation between statistics anxiety (CSCS), statistics self-efficacy (CSSE and SELS), and course performance. There was high internal reliability for each instrument's items making the instruments suitable for use with graduate students. However, none of the instruments' results were significant in relation to course performance with graduate students in this sample. Unlike prior research involving undergraduate-level statistic students that has reported a relationship between the CSSE and SELS, the present study, involving graduate students, did not find any significant correlation with performance. Additional research is suggested to investigate the reasons for the differences between the studies.

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Wong, Sik-kwan Francis. "Outcome of a web-based statistic laboratory for teaching and learning of medical statistics". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43251687.

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42

Friedrich, Oliver [Verfasser], e Ralf [Akademischer Betreuer] Bender. "Statistical properties of the cosmic density field beyond 2-point statistics : covariance matrices and density split statistics / Oliver Friedrich ; Betreuer: Ralf Bender". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1178323749/34.

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43

Friedrich, Oliver Verfasser], e Ralf [Akademischer Betreuer] [Bender. "Statistical properties of the cosmic density field beyond 2-point statistics : covariance matrices and density split statistics / Oliver Friedrich ; Betreuer: Ralf Bender". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1178323749/34.

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44

Lesser, Elizabeth Rochelle. "A New Right Tailed Test of the Ratio of Variances". UNF Digital Commons, 2016. http://digitalcommons.unf.edu/etd/719.

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It is important to be able to compare variances efficiently and accurately regardless of the parent populations. This study proposes a new right tailed test for the ratio of two variances using the Edgeworth’s expansion. To study the Type I error rate and Power performance, simulation was performed on the new test with various combinations of symmetric and skewed distributions. It is found to have more controlled Type I error rates than the existing tests. Additionally, it also has sufficient power. Therefore, the newly derived test provides a good robust alternative to the already existing methods.

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Thayne, Jeffrey L. "Making Statistics Matter: Using Self-data to Improve Statistics Learning". DigitalCommons@USU, 2016. https://digitalcommons.usu.edu/etd/5214.

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Research has demonstrated that well into their undergraduate and even graduate education, learners often struggle to understand basic statistical concepts, fail to see their relevance in their personal and professional lives, and often treat them as little more than mere mathematics exercises. This study explored ways help learners in an undergraduate learning context to treat statistical inquiry as mattering in a practical research context, by inviting them to ask questions about and analyze large, real, messy datasets that they have collected about their own personal lives (i.e., self-data). This study examined the conditions under which such an intervention might (and might not) successfully lead to a greater sense of the relevance of statistics to undergraduate learners.

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46

Audibert, Jean-Yves. "PAC-Bayesian aggregation and multi-armed bandits". Habilitation à diriger des recherches, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00843972.

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This habilitation thesis presents several contributions to (1) the PAC-Bayesian analysis of statistical learning, (2) the three aggregation problems: given d functions, how to predict as well as (i) the best of these d functions (model selection type aggregation), (ii) the best convex combination of these d functions, (iii) the best linear combination of these d functions, (3) the multi-armed bandit problems.

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47

Karlsson, Maria. "Estimators of semiparametric truncated and censored regression models". Doctoral thesis, Umeå : Department of Statistics, UmeåUniversity, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-540.

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48

Lindblad, Niclas. "Subversion Statistics Tool". Thesis, Linköping University, Department of Computer and Information Science, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15792.

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På Linköpings universitet använder man sig sällan av versionshanteringssystem i kurser. Istället sparas till exempel programmeringslabbar på enskilda personers UNIX konton. Detta leder till problem både när man programmerar i grupp men också om någonting skulle gå snett. Labhandledaren har också mycket sämre vetskap om hur specifika gruppers arbeten framskrider och många grupper kan få hjälp för sent på grund av detta. Troligtvis kommer versionshanteringssystem användas mycket mer i framtiden.

Att läsa versionsloggar för att följa upp grupper är ett osmidigt och tidskrävande jobb och ger dålig överblick. Detta examensarbete beskriver ett verktyg till hjälp för labhandledaren i kurser där versionshanteringssystem används. Tillvägagångssättet och designen men även vilka problem som uppstod är fokus i rapporten.

Resultatet av examensarbetet är en webapplikation som visar statistik för alla labgrupper i en specifik kurs, både textuellt och grafiskt. Webapplikationen strävar efter att bete sig som en vanlig och lättanvänd skrivbordsapplikation. Detta verktyg ger labhandledaren bättre överblick över individernas arbete samtidigt som fusk kan komma att uppmärksammas.

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49

Karlslätt, David. "Improved Statistics Handling". Thesis, Linköping University, Department of Computer and Information Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-18238.

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Ericsson is a global provider of telecommunications systems equipment and related services for mobile and fixed network operators.

3Gsim is a tool used by Ericsson in tests of the 3G RNC node.

In order to validate the tests, statistics are constantly gathered within 3Gsim and users can use telnet to access the statistics using some system specific 3Gsim commands.

The statistics can be retrieved but is unstructured for the human eye and needs parsing and arranging to be readable.

The statistics handler that is implemented during this thesis provides a possibility for users of 3Gsim to present information that favors their personal interest.

The implementation can produce one prototype output document which contains the most common statistics needed by the 3Gsim user. A main focus of this final thesis has been to simplify content and format control for the user as much as possible.

Presenting and structuring information now comes down to simple text editing and rid the user of the time consuming work of updating and recompiling the entire application.

Earlier, scripts written in Perl, an iterative oriented language, were used for presenting the statistics. These scripts were often difficult to comprehend since there were many different authors with inadequate experience and knowledge.

The new statistics handler has been written in Java, a high-level object-oriented language which should better suite the users and developers of 3Gsim.

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Ghoudi, Kilani. "Multivariate randomness statistics". Thesis, University of Ottawa (Canada), 1993. http://dx.doi.org/10.20381/ruor-17165.

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During the startup phase of a production process while statistics on the product quality are being collected it is useful to establish that the process is under control. Small samples ni qi=1 are taken periodically for q periods. We shall assume each measurement is multivariate. A process is under control or on-target if all the observations are deemed to be independent and identically distributed. Let Fi represent the empirical distribution function of the ith sample. Let F¯ represent the empirical distribution function of all observations. Following Lehmann (1951) we propose statistics of the form i=1q -infinityinfinityFi s-F- s2d Fs. The asymptotics of nonparametric q-sample Cramer-Von Mises statistics were studied in Kiefer (1959). The emphasis there, however, is on the case where n(i) → infinity while q stayed fixed. Here we study the asymptotics of a family of randomness statistics, that includes the above. These asymptotics are in the quality control situation (i.e q → infinity while n( i) stay fixed). Such statistics can be used in many situations; in fact one can use randomness statistics in any situation where the problem amounts to a test of homoscedasticity or homogeneity of a collection of observations. We give two such applications. First we show how such statistics can be used in nonparametric regression. Second we illustrate the application to retrospective quality control.

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Tesi sul tema "Statistics"

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