Bibliografías temáticas / Longitudinal data sets

Índice

Artículos de revistas
Tesis
Libros
Capítulos de libros
Actas de conferencias
Informes

Literatura académica sobre el tema "Longitudinal data sets"

Autor: Grafiati

Publicado: 25 de mayo de 2024

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte las listas temáticas de artículos, libros, tesis, actas de conferencias y otras fuentes académicas sobre el tema "Longitudinal data sets".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Artículos de revistas sobre el tema "Longitudinal data sets"

Valenstein, Marcia. "The Promise of Large, Longitudinal Data Sets". Psychiatric Services 64, n.º 6 (junio de 2013): 503. http://dx.doi.org/10.1176/appi.ps.201300134.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Schneiderman, Emet D., Charles J. Kowalski y Stephen M. Willis. "Regression imputation of missing values in longitudinal data sets". International Journal of Bio-Medical Computing 32, n.º 2 (marzo de 1993): 121–33. http://dx.doi.org/10.1016/0020-7101(93)90051-7.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Bône, Alexandre, Olivier Colliot y Stanley Durrleman. "Learning the spatiotemporal variability in longitudinal shape data sets". International Journal of Computer Vision 128, n.º 12 (2 de julio de 2020): 2873–96. http://dx.doi.org/10.1007/s11263-020-01343-w.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Prahl-Andersen, B. y C. Kowalski. "Analysis of Cohort Effects in Mixed Longitudinal Data Sets". International Journal of Sports Medicine 18, S 3 (julio de 1997): S186—S190. http://dx.doi.org/10.1055/s-2007-972712.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Evans, William N., Helen Levy y Kosali I. Simon. "Data Watch: Research Data in Health Economics". Journal of Economic Perspectives 14, n.º 4 (1 de noviembre de 2000): 203–16. http://dx.doi.org/10.1257/jep.14.4.203.

Texto completo

Resumen

In this paper, we discuss some important data sets that can be used by economists interested in conducting research in health economics. We describe six types of data sets: health components of data sets traditionally used by economists; longitudinal surveys of health and economic behavior; data on employer-provided insurance; cross-sectional surveys of households that focus on health; data on health care providers; and vital statistics. We summarize some of the leading surveys, discuss the availability of the data, identify how researchers have utilized these data and when possible, include a web address that contains more detailed information about each survey.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Carstensen, Laura L. "Peril in the Prediction of Psychopathology From Longitudinal Data Sets". Contemporary Psychology: A Journal of Reviews 34, n.º 4 (abril de 1989): 344–45. http://dx.doi.org/10.1037/027884.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Dawson, Deborah V. y Ilene C. Siegler. "Approaches to the nonparametric analysis of limited longitudinal data sets". Experimental Aging Research 22, n.º 1 (enero de 1996): 33–57. http://dx.doi.org/10.1080/03610739608253996.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Bryan, Julia A., Norma L. Day-Vines, Cheryl Holcomb-McCoy y Cheryl Moore-Thomas. "Using National Education Longitudinal Data Sets in School Counseling Research". Counselor Education and Supervision 49, n.º 4 (junio de 2010): 266–79. http://dx.doi.org/10.1002/j.1556-6978.2010.tb00102.x.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Reith, Nicholas E., Pamela Paxton y Melanie M. Hughes. "Building Cross-National, Longitudinal Data Sets: Issues and Strategies for Implementation". International Journal of Sociology 46, n.º 1 (2 de enero de 2016): 21–41. http://dx.doi.org/10.1080/00207659.2016.1130416.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Barham, Catherine y Nasima Begum. "Time series analysis of the Labour Force Survey longitudinal data sets". Economic & Labour Market Review 1, n.º 1 (enero de 2007): 48–53. http://dx.doi.org/10.1057/palgrave.elmr.1410012.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Más fuentes

Tesis sobre el tema "Longitudinal data sets"

Liu, Rong. "A Comparison for Longitudinal Data Missing Due to Truncation". VCU Scholars Compass, 2006. http://hdl.handle.net/10156/1755.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

MONGELLUZZO, SILVIA. "Bayesian semiparametric inference for longitudinal data with applications". Doctoral thesis, Università Bocconi, 2013. https://hdl.handle.net/11565/4054325.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

MAZZOLENI, MARCELLA. "Joint models for time-to-event and multivariate longitudinal data". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2015. http://hdl.handle.net/10281/95620.

Texto completo

Resumen

The joint models for longitudinal and time-to-event data are a recent family models that jointly analyse the longitudinal and the survival data. The models are composed by two sub-models, the longitudinal and the survival sub-model. A proportional hazard model can be used for survival sub-model and it is expressed in function of the true and unobserved value of the longitudinal outcome, while concerning the longitudinal sub-model a linear mixed model is often proposed. After analysing some univariate cases, it is interesting to study the situation in which one of the two sub-models or both are multivariate. Thus different scenarios are possible. Firstly it is possible to consider a situation in which only the longitudinal sub-model is multivariate, in this situation a multivariate linear mixed model or another type of multivariate longitudinal model can be considered. Choosing a multivariate linear mixed-effects model, a different longitudinal outcome must be considered for each linear predictor. Accordingly the survival sub-model is composed by several parameters that express the relation of each true and unobserved value of the longitudinal outcome with the hazard function. Secondly a situation in which only the survival sub-model is multivariate is possible, thus the survival sub-model may consider two situations, competing risks or recurrent events. Lastly a situation in which both the longitudinal and the survival model are multivariate must be considered. The sub-models are composed by the multivariate longitudinal and survival sub-models which are jointly analysed. The biggest problem related to the multivariate situation concerns the computational aspect of the estimation. In fact considering that the univariate case is computational demanding, increasing the number of the parameters or the dimension of the sub-models will lead to higher computational demanding situations. This problem could be solved with the implementation of some algorithms in the R software that could reduce the time and the memory requested. In this thesis the focus is on the situation in which only the longitudinal sub-model is multivariate. The aim is to find new methods of estimation and some algorithms that could help to solve the problem of the computational aspect. At first a two stages approach is implemented as it permits to obtain very fast and significant estimations. The most of the applications of joint models focus on the biostatistical area, thus the event analysed is death or the manifestation of a disease and the influence of some biomarkers on it. In this thesis the focus is on the undergraduates' career, analysing the careers of the undergraduate students in an Italian university, using jointly the time to graduation and the student's path, focusing on the marks and on the number of exams that the student has already passed before a fixed time. The algorithms are implemented also on a well-known biostatistical data set available in the package JM of the software R the test the reliability and the efficiency.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Sgargi, Daria <1986&gt. "The analysis of survival and longitudinal data from life-span carcinogenicity bioassay on Sprague-Dowley rats". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8303/1/sgargi_daria_tesi.pdf.

Texto completo

Resumen

Carcinogenicity bioassay are among the best instruments to strengthen the evidence on which regulatory agencies vase their decision to classify harmful agents as human carcinogens, so they are fundamental to protect public health. The statistical analysis is fundamental to validate the results from carcinogenicity bioassay. This work aims to propose and illustrate some methodologies for the analysis of non-cancer outcomes, in particular for the analysis of time-to-death and of longitudinal measurements of body weights. The data from an old experiment were used for this purpose: 4 experiments aimed at testing the carcinogenic potential of Coca-Cola on Sprague-Dawley rats of different ages (randomized males and females of 7, 30, 39, 55 weeks of age, and their non-randomized offspring, observed since birth) were re-analysed. Survival analysis aimed to verify the influence of the treatment, controlling for possible differences due to sex, age at beginning of observation and age of the dams at pregnancy. It was performed using Cox proportional hazards models for the rats of second generation, and accelerated failure-times models for those of first generation; the use of frailty terms was evaluated (univariate gamma frailty to account for unobserved heterogeneity applied to data from breeders; shared gamma frailty at the litter level applied to data from offspring). The analysis of longitudinal body weights of the offspring was aimed at verifying the relevance of treatment, controlling for physiological differences due to sex and age of the dams at gestation. It was performed using linear and nonlinear mixed-effects models to handle the hierarchical structure of the data. Linear models were fitted using log-transformation of time and polynomial terms of order 3; nonlinear models consisted of growth models, in particular the Berkey-Reed model, that is usually used to analyse human growth during infancy, was applied.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Bazzocchi, Marika <1991&gt. "Inequality of income and poverty persistence in the Municipality of Bologna: a cross-sectional and longitudinal analysis through administrative data". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10335/1/Main.pdf.

Texto completo

Resumen

This work is part of a project promoted by Emilia-Romagna that aims at encouraging research activities in order to support the innovation strategies of the regional economic system through the exploitation of new data sources. To gain this scope, a database containing administrative data is provided by the Municipality of Bologna. This is achieved by linking data from the Register Office of the Municipality and fiscal data coming from the tax returns submitted to the Revenue Agency and released by the Ministry of Economy and Finance for the period 2002-2017. The main purpose of the project is the analysis of the medium term financial and distributional trends of income of the citizens residing in the Municipality of Bologna. Exploiting this innovative source of data allow us to analyse the dynamics of income at municipal level, overcoming the lack of information in official survey-based statistic. We investigate these trends by building inequality indicators and by examining the persistence of in-work poverty. Our results represent an important informative element to improve the effectiveness and equity of welfare policies at the local level, and to guide the distribution of economic and social support and urban redevelopment interventions in different areas of the Municipality.

Los estilos APA, Harvard, Vancouver, ISO, etc.

AMATI, VIVIANA. "New statistics for the parameters estimation of the stochastic actor-oriented model for network change". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2011. http://hdl.handle.net/10281/19389.

Texto completo

Resumen

The Stochastic actor-oriented model (SAO) is a statistical model for longitudinal network data. The most often used procedure for the estimation of the parameter of the SAO model is the Method of Moments (MoM), which estimates the parameters using one observed statistic for each estimated parameter. A new set of statistics is defined taking into account the different ways of creating and deleting ties to which a certain effect can contribute. This definition leads to having more than one statistic for a single parameter, i.e. to an over-determined system of equations. Thus, the ordinary MoM cannot be applied. A suitable method then is the Generalized Method of Moments (GMM), an estimation technique mainly used in econometrics, and potentially more efficient than the MoM. Like the regular MoM, the GMM is based on the differences between the expected values of the statistics and their sample counterparts, but the GMM involves the minimization of a quadratic function of these differences rather than setting all differences to 0. This means that an extra problem arises: the determination of a matrix of weights reflecting the different importance and correlations of the statistics involved. An optimization-simulation algorithm is used, following the approach suggested by Gelman (1995) and based on the Newton-Raphson algorithm, to compare the estimators deriving from the MoM and the GMM. Simulation results suggest that the new set of statistics performs better when network observations are close. In fact, in this context the standard errors of the GMM estimators are lower than those of the MoM.

Los estilos APA, Harvard, Vancouver, ISO, etc.

COMUNE, MARIA ELENA. "DISEGUAGLIANZE DEI REDDITI E POVERTA' DELLE FAMIGLIE ATTRAV ERSO DATI AMMINISTRATIVI. UN'INDAGINE LONGITIDINALE NEL COMUNE DI BRESCIA". Doctoral thesis, Università Cattolica del Sacro Cuore, 2012. http://hdl.handle.net/10280/1249.

Texto completo

Resumen

In questo studio, attraverso la realizzazione di un’indagine longitudinale basata su dati amministrativi, sono stati ricostruiti i redditi delle famiglie residenti nel comune di Brescia per gli anni 2005-2008, in una prospettiva trasversale e longitudinale, individuando situazioni di disuguaglianza, di disagio e povertà economica di alcune fasce della popolazione. L’indagine longitudinale è stata realizzata mediante il record-linkage tra i dati amministrativi provenienti dall’Anagrafe comunale e quelli fiscali del Sistema Interscambio Anagrafe Tributaria Enti Locali dell’Agenzia delle Entrate (SIATEL) per il comune di Brescia. La peculiarità e l’importanza di questo lavoro risiedono sia nell’utilizzare dati di fonte amministrativa fiscale e anagrafica nella stima sui redditi e povertà delle famiglie, sia nella possibilità di ottenere stime a livello comunale o small-area, ampliando il campo della ricerca sociale sul tema oggetto di studio. L’approccio teorico di riferimento adottato è quello unidimensionale, basato sul reddito, e relativo, in cui la povertà è definita in relazione allo standard di benessere raggiunto dalla popolazione di riferimento nel suo complesso. Pertanto, anziché la soglia di povertà nazionale, che tende a sottostimare la povertà nel nord d’Italia, è stata adottata una soglia di povertà locale, pari al 60% del reddito mediano equivalente delle famiglie residenti.
In this study the incomes of the families residing in the town of Brescia for the years 2005-2008 have been simulated in a cross-section and longitudinal perspective, through the creation of a Panel based on administrative data. The research aimed at identifying situations of inequality, dislocation and economic poverty of certain population groups. The Panel was carried out on the basis of the record-linkage administrative data from Registry Office and ” Informatics’ System of Local Italian Revenue Agency” (SIATEL), for the town of Brescia. The uniqueness and importance of this work is the use of live data in estimating income and family poverty using fiscal and personal data from registry office sources, as well as in the availability of estimates at the municipal level or small-area, thus expanding the social research on the subject of study. The theoretical approach adopted by reference is one-dimensional (based on income) and relative, in which poverty is defined in relation to the standards being achieved by the reference population as a whole. Therefore, instead of the national poverty line, which tends to underestimate poverty in northern Italy, a local poverty threshold was adopted, equal to 60% of equivalised median income of the families residing in the town of Brescia.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Texto completo

Resumen

Los estilos APA, Harvard, Vancouver, ISO, etc.

BRIGLIA, ANDREA. "Statistical and computational approaches to first language acquisition. Mining a set of French longitudinal corpora (CoLaJE)". Doctoral thesis, 2021. http://hdl.handle.net/11570/3193136.

Texto completo

Resumen

This thesis is based on a French datasets composed by seven longitudinal corpora of child spoken language. Each monthly transcript can be turned in a machine-readable spreasheet which is the base of all the computations that have been made, as well as the related graphical visualisations. Hypotheses about phonemes acquisition, phonological acquisition and grammar acquisition have been tested by using tools and concept from descriptive and inferential statistics, regression (chi squared) and clustering. A complete part-of-speech tagging of around 15'000 sentences is proposed to study the emergence of syntax (from one-word to multi-word utterances). A convolutional neural network trained on the same dataset is proposed and the accuracy of its prediction is discussed. A final consideration on the importance of modelling phonetic variations within the syllable level is finally discussed, as the main limit of the thesis has been to having put aside the coarticulatory differences that a given phoneme can have according to the place it occupies in the syllable structure (onset-nucleus-coda).

Los estilos APA, Harvard, Vancouver, ISO, etc.

Libros sobre el tema "Longitudinal data sets"

L, Arnold Carolyn. Using national data sets to create comparable national statistics for the student characteristics and outcomes in community colleges. Hayward, Calif: Chabot College, Office of Institutional Research, 1997.

Buscar texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Stull, Judith C. Large data sets: Opportunities and challenges for educational researchers / by Judith C. Stull, Nancy Morse-Kelly, Leo C. Rigsby. [Washington, DC]: U.S. Dept. of Education, Office of Educational Research and Improvement, Educational Resources Information Center, 1995.

Buscar texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Welsman, Joanne R. y Neil Armstrong. Interpreting exercise performance data in relation to body size. Oxford University Press, 2013. http://dx.doi.org/10.1093/med/9780199232482.003.0002.

Texto completo

Resumen

The appropriate normalization of exercise performance data for differences in body size underpins the clarification of growth and maturational influences on physiological function. Therefore, scaling is an issue of fundamental importance for all paediatric exercise scientists. The selection and application of a scaling method appropriate for the data and research question being addressed is at least as important as ensuring that the methodology used to collect the data is valid, reliable, and appropriate for use with young people. Several scaling methods are available and some methods can be applied in different ways. Unfortunately, taken as a whole, the extant literature presents a confusing picture as to which of these techniques is preferable, how they should be applied, and the meaning of the results obtained. The aim of this chapter is to clarify these issues through a description of the techniques available for analysing both cross-sectional and longitudinal data sets, highlighting their statistical and theoretical derivations.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Snijders, Tom A. B. y Mark Pickup. Stochastic Actor Oriented Models for Network Dynamics. Editado por Jennifer Nicoll Victor, Alexander H. Montgomery y Mark Lubell. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780190228217.013.10.

Texto completo

Resumen

Stochastic Actor Oriented Models for Network Dynamics are used for the statistical analysis of longitudinal network data collected as a panel. The probability model defines an unobserved stochastic process of tie changes, where social actors add new ties or drop existing ties in response to the current network structure; the panel observations are snapshots of the resulting changing network. The statistical analysis is based on computer simulations of this process, which provides a great deal of flexibility in representing data constraints and dependence structures. In this Chapter we begin by defining the basic model. We then explicate a new model for nondirected ties, including several options for the specification of how pairs of actors coordinate tie changes. Next, we describe coevolution models. These can be used to model the dynamics of several interdependent sets of variables, such as the analysis of panel data on a network and the behavior of the actors in the network, or panel data on two or more networks. We finish by discussing the differences between Stochastic Actor Oriented Models and some other longitudinal network models. A major distinguishing feature is the treatment of time, which allows straightforward application of the model to panel data with different time lags between waves. We provide a variety of applications in political science throughout.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Claessens, Albrecht L., Gaston Beunen y Robert M. Malina. Anthropometry, physique, body composition, and maturity. Oxford University Press, 2013. http://dx.doi.org/10.1093/med/9780199232482.003.0003.

Texto completo

Resumen

Los estilos APA, Harvard, Vancouver, ISO, etc.

Desmarais, Bruce A. y Skyler J. Cranmer. Statistical Inference in Political Networks Research. Editado por Jennifer Nicoll Victor, Alexander H. Montgomery y Mark Lubell. Oxford University Press, 2016. http://dx.doi.org/10.1093/oxfordhb/9780190228217.013.8.

Texto completo

Resumen

Researchers interested in statistically modeling network data have a well-established and quickly growing set of approaches from which to choose. Several of these methods have been regularly applied in research on political networks, while others have yet to permeate the field. This chapter reviews the most prominent methods of inferential network analysis for both cross-sectionally and longitudinally observed networks, including (temporal) exponential random graph models, latent space models, the quadratic assignment procedure, and stochastic actor oriented models. For each method, the chapter summarizes its analytic form, identifies prominent published applications in political science, and discusses computational considerations. It concludes with a set of guidelines for selecting a method for a given application.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Pratt, Michael W. y M. Kyle Matsuba. Parent and Grandparent Relationships in Emerging Adulthood. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199934263.003.0007.

Texto completo

Resumen

Chapter 7 begins with an overview of Erikson’s ideas about intimacy and its place in the life cycle, followed by a summary of Bowlby and Ainsworth’s attachment theory framework and its relation to family development. The authors review existing longitudinal research on the development of family relationships in adolescence and emerging adulthood, focusing on evidence with regard to links to McAdams and Pals’ personality model. They discuss the evidence, both questionnaire and narrative, from the Futures Study data set on family relationships, including emerging adults’ relations with parents and, separately, with grandparents, as well as their anticipations of their own parenthood. As a way of illustrating the key personality concepts from this family chapter, the authors end with a case study of Jane Fonda in youth and her father, Henry Fonda, to illustrate these issues through the lives of a 20th-century Hollywood dynasty of actors.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Power, Sally, ed. Civil Society through the Lifecourse. Policy Press, 2020. http://dx.doi.org/10.1332/policypress/9781447354833.001.0001.

Texto completo

Resumen

This edited collection explores the temporal dimensions of civil society through examining how different lifecourse stages and events trigger or hinder engagement with civil society. There is increasing concern about declining levels of participation, and fears that young people today are far less civically engaged than older generations. Some believe that an already-weakened civil society looks set to enter a phase of terminal decline. However, these gloomy predictions do not consider the possibility not only that the nature of civic engagement may be changing, but that participation may wax and wane over the lifecourse. Drawing on a range of empirical data, including cross-sectional analyses, longitudinal data and interviews, this book investigates not changing levels of engagement, and the shifting priorities of citizens as they manage the contingencies of career, family and old age. Largely chronological in organisation, this book explores civic participation over the lifecourse – from school to later life. The book includes chapters on young people’s civil and political participation and the role of universities in promoting civic engagement. It also examines the challenges of parenthood and grandparenthood – as well as the opportunities for volunteering in later life. Finally, the examines how older people balance the competing claims of charities and family when thinking about their legacy.

Los estilos APA, Harvard, Vancouver, ISO, etc.

de Waal, André A. High Performance Managerial Leadership. ABC-CLIO, LLC, 2020. http://dx.doi.org/10.5040/9798400663321.

Texto completo

Resumen

Learn how managers have transformed their teams and companies into envied high-performance organizations in this guide to nurturing successful managers at your organization, informed by the author's 10-year study of applications of his High Performing Organization (HPO) Framework. How can an organization learn to perform at a high level? The key is management. Based on years of intensive research and experience, André de Waal's proven strategy for achieving positive organizational change can turn your company or team into a true High Performance Organization (HPO). De Waal's HPO Framework is the only management improvement technique that has been developed on a solid scientific basis, validated through longitudinal site-level research, and developed over years of measuring organizational results. In this book, de Waal focuses on the activities and behaviors of managers in organizations that have successfully transformed themselves into HPOs. The author and his team closely followed and measured organizations that have adopted and applied the HPO Framework over many years, uncovering the secrets to creating successful and transformative managers through the use of HPO coaches, the application of "silo-busting" techniques to spur collaboration, and use of the HPO transformation success wheel. The resulting data set, analytics, and lessons presented represent a treasure trove of actionable tools for achieving successful managerial and organizational change and improvement.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Capítulos de libros sobre el tema "Longitudinal data sets"

Anguita-Ruiz, Augusto, Alberto Segura-Delgado, Rafael Alcala, Concepción Maria Aguilera y Jesus Alcala-Fernandez. "Describing Sequential Association Patterns from Longitudinal Microarray Data Sets in Humans". En Bioinformatics and Biomedical Engineering, 318–29. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-17935-9_29.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Berk, Maurice, Cheryl Hemingway, Michael Levin y Giovanni Montana. "Longitudinal Analysis of Gene Expression Profiles Using Functional Mixed-Effects Models". En Advanced Statistical Methods for the Analysis of Large Data-Sets, 57–67. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-21037-2_6.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Debavelaere, Vianney, Alexandre Bône, Stanley Durrleman y Stéphanie Allassonnière. "Clustering of Longitudinal Shape Data Sets Using Mixture of Separate or Branching Trajectories". En Lecture Notes in Computer Science, 66–74. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32251-9_8.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Belloc, Filippo, Antonello Maruotti y Lea Petrella. "A Correlated Random Effects Model for Longitudinal Data with Non-ignorable Drop-Out: An Application to University Student Performance". En Advanced Statistical Methods for the Analysis of Large Data-Sets, 127–36. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-21037-2_12.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Sibbritt, David y Jon Adams. "Utilizing existing data sets to investigate complementary and alternative medicine consumption: Cohort studies and longitudinal analyses". En Traditional, Complementary and Integrative Medicine, 26–32. London: Macmillan Education UK, 2012. http://dx.doi.org/10.1007/978-1-137-26559-3_4.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Elliott, Jane. "Data Through Time: Figuring Out the Narrative Self in Longitudinal Research". En Figure, 173–96. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-2476-7_9.

Texto completo

Resumen

AbstractThis chapter explores the ways in which individuals have figured within longitudinal research in the social sciences. It raises questions about the implications of the self-tracking movement, and ‘personal informatics’, for future research practices. This chapter discusses the importance of focusing on what can be considered as ‘figure’ and ‘ground’ in research and in representations of individuals’ lives. There is a focus on understanding figure and ground in temporal terms—contrasting the events and experiences that structure personal life narratives with the routines of daily life which are often almost unnoticed. This chapter draws on exemplars from Britain’s portfolio of national longitudinal studies of individuals’ lives and highlights an emerging set of methods focused on reconstructing individual cases within quantitative longitudinal research.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Salinas Ruíz, Josafhat, Osval Antonio Montesinos López, Gabriela Hernández Ramírez y Jose Crossa Hiriart. "Generalized Linear Mixed Models for Repeated Measurements". En Generalized Linear Mixed Models with Applications in Agriculture and Biology, 377–423. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-32800-8_9.

Texto completo

Resumen

AbstractRepeated measures data, also known as longitudinal data, are those derived from experiments in which observations are made on the same experimental units at various planned times. These experiments can be of the regression or analysis of variance (ANOVA) type, can contain two or more treatments, and are set up using familiar designs, such as CRD (Completely Randomized design), randomized complete block design (RCBD), or randomized incomplete blocks, if blocking is appropriate, or using row and column designs such as Latin squares when appropriate. Repeated measures designs are widely used in the biological sciences and are fairly well understood for normally distributed data but less so with binary, ordinal, count data, and so on. Nevertheless, recent developments in statistical computing methodology and software have greatly increased the number of tools available for analyzing categorical data.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Nilsen, Ann. "The Origins of Biographical and Life Course Research". En Biographical Life Course Research, 23–44. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-44717-4_2.

Texto completo

Resumen

AbstractThis chapter, on the origins of biographical and life course research, draws the lines from American pragmatism which started from a processual approach with time and temporality as central features. George Herbert Mead’s concept of the processual self provides an entry point for understanding biographical material. Crucial to the development of this approach was the meeting place provided by Hull House. The women at this charity, Jane Addams in particular, contributed to the methodological innovations of Chicago sociology. The funder of the charity provided a grant for William I Thomas study that he published with Florian Znaniecki, The Polish Peasant in Europe and America. This first example of a sociological study that applied biographical material is presented. It discusses how this work only received recognition when Herbert Blumer chaired the Appraisal proceedings of it at an ASA session in 1938. C. Wright Mills’ book The Sociological Imagination made the dynamic history-biography relationship an inspiration for later biographical life course research. The chapter ends with a discussion of Glen Elder’s classic study Children of the Great Depression and demonstrates how Elder’s inspiration from Mills set his approach to the analysis of longitudinal data apart from those who sought to uncover ‘laws of social deviance’ through longitudinal studies.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Salinas Ruíz, Josafhat, Osval Antonio Montesinos López, Gabriela Hernández Ramírez y Jose Crossa Hiriart. "Generalized Linear Mixed Models for Non-normal Responses". En Generalized Linear Mixed Models with Applications in Agriculture and Biology, 113–27. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-32800-8_4.

Texto completo

Resumen

AbstractGeneralized linear mixed models (GLMMs) have been recognized as one of the major methodological developments in recent years, which is evidenced by the increased use of such sophisticated statistical tools with broader applicability and flexibility. This family of models can be applied to a wide range of different data types (continuous, categorical (nominal or ordinal), percentages, and counts), and each is appropriate for a specific type of data. This modern methodology allows data to be described through a distribution of the exponential family that best fits the response variable. These complex models were not computationally possible up until recently when advances in statistical software have allowed users to apply GLMMs (Zuur et al. 2009; Stroup 2012; Zuur et al. 2013). Researchers in fields other than statistical science are also interested in modeling the structure of data. For example, in the social sciences there have been applications in the field of education when several tests are applied to students; in longitudinal personality studies when the occurrence of an emotion is repeatedly observed over time over a set of people; and in surveys to investigate the political preference of a population, among others.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Décieux, Jean Philippe. "Is There More Than the Answer to the Question? Device Use and Completion Time as Indicators for Selectivity Bias and Response Convenience in Online Surveys". En IMISCOE Research Series, 309–24. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-67498-4_17.

Texto completo

Resumen

AbstractThe main objective of the German Emigration and Remigration Panel Study (GERPS) is to establish a longitudinal data set that provides information on life trajectories of international migrants. However, a large amount of paradata were also collected in order to obtain meta-information on respondents’ survey participation. This auxiliary information can help to optimize data quality at all stages of the survey process. By continuing the existing discussion in the field of online surveys, this chapter pursues a twofold objective: it reflects device usage (mobile vs. computer) and elucidates determinants of device choice. In particular, it analyses whether selectivity effects due to respondent’s device choices bias the sample. Moreover, this chapter investigates differences in response time between devices to detect differences in response burden. The analysis of response burden differences by device is an important issue, since an increased device-specific response burden can be a predictor of actual and further panel dropouts. In both device-specific selectivity and survey burden, only slight differences were found between mobile and desktop devices. Using these data, the following paper addresses the need to analyse potential sources of survey error and provides evidence that GERPS data do not appear to contain noteworthy bias attributed to device usage.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Actas de conferencias sobre el tema "Longitudinal data sets"

Prommegger, Bernhard, Christof Kauba y Andreas Uhl. "On the Extent of Longitudinal Finger Rotation in Publicly Available Finger Vein Data Sets". En 2019 International Conference on Biometrics (ICB). IEEE, 2019. http://dx.doi.org/10.1109/icb45273.2019.8987384.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Timmins, Lucas H., Jonathan D. Suever, Parham Eshtehardi, Michael C. McDaniel, Habib Samady, John N. Oshinski y Don P. Giddens. "Correlation of Longitudinal Intravascular Ultrasound Data for the Clinical Assessment of Coronary Artery Disease Progression". En ASME 2012 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/sbc2012-80630.

Texto completo

Resumen

Virtual histology-intravascular ultrasound (VH-IVUS) has gained increasing utility in the cardiac catheterization laboratory, not only in determining underlying atherosclerotic lesion composition prior to stent placement, but also in clinical studies assessing the natural history of coronary artery disease (CAD) [1]. Furthermore, VH-IVUS has provided an excellent means of quantifying disease progression by comparing data sets collected over time (i.e., longitudinal studies) and potentially identifying rapidly progressing and potentially vulnerable plaques. One difficulty, however, in analyzing VH-IVUS derived CAD progression is the accurate co-registration of image sets collected over a period of time. Commonly, an expert VH-IVUS image reader reviews these image sets side-by-side on a display and co-registers images along the vessel main axis, herein axially co-registered, by identifying image locations relative to fiduciary anatomical markers (e.g., branches). Despite this method being the standard for analyzing CAD progression, it is limited by the inability to accurately co-register VH-IVUS data in the circumferential direction (i.e., rotating images such that their cylindrical coordinate bases coincide; herein circumferentially co-registered). Thus, a significant amount of information on focal plaque progression is lost that could provide a greater understanding of the natural evolution of CAD, the effects of various pharmaceutical agents (e.g., statins) on lesion composition changes, and the impact of local mechanical factors that induce plaque progression/regression and transformation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Heffernan, Matthew E. y David Bevly. "Validation of Longitudinal Vehicle Estimation Techniques on a Heavy Truck Test-Bed". En ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81901.

Texto completo

Resumen

Commercial vehicles display a large variation in their parameters, and due to many current trends in vehicle control systems, identifying these parameters has been the subject of much research. Using the National Center for Asphalt Technology’s test track and instrumented Freightliner vehicles as a test bed, this paper sets out to provide analysis of real world and simulated estimation results and explore how sensor accuracies can degrade these results. Various vehicle parameters are identified using both the existing test conditions of the facility and simulated data. The estimation accuracy and performance are then analyzed for validation and use in other vehicle design arenas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Hosseini, Sayedmohammad, Arash Hosseinian Ahangarnejad, Ahmad Radmehr, Ali Tajaddini y Mehdi Ahmadian. "A Statistical Approach to Evaluating Wheel-Rail Contact Dynamics". En 2021 Joint Rail Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/jrc2021-58381.

Texto completo

Resumen

Abstract This paper provides a statistical analysis of the effects of wheel load, angle of attack (AoA), and creepage on longitudinal traction force at the wheel-rail contact using experimental data collected on the Virginia Tech-Federal Railroad Administration (VT-FRA) Roller Rig. The VT-FRA Roller Rig is a unique piece of equipment designed and built with the specific goal of evaluating the wheel-rail contact mechanics and dynamics with a high degree of precision. Longitudinal traction forces are of great importance to the railroad industry since they provide the motive power needed to move a train. Various experiments are conducted in different settings to study the relationship between the aforementioned variables and the longitudinal traction force. The test data is split into “training” and “testing” sets, and the training sets (a total of four) are used to entertain statistical models in a standard parametric regression framework. The study carefully assesses whether the assumptions of the classical linear regression model hold by studying the empirical histogram and the normal Q-Q plot of the residuals. In the case of non-linearities, different transformations are applied to the explanatory variable to find the closest functional form that captures the relationship between the response and the explanatory variables. The developed models are then compared with their non-parametric counterparts such as natural cubic splines in terms of goodness of fit, and prediction error on the testing set. The study develops regression models that are able to accurately explain the relationship between longitudinal traction and creepage and AoA. The models are intended to be used for predicting traction under various operating conditions.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ratcliffe, Toby y Michael Wilson. "Uncertainty in Measurement of Ship Model Wave Profiles and Wave Pattern Resistance". En SNAME 22nd American Towing Tank Conference. SNAME, 1989. http://dx.doi.org/10.5957/attc-1989-047.

Texto completo

Resumen

Two sets of longitudinal wave cut data serve as the basis for estimating the measurement uncertainty associated with the ship model waves profiles and wave pattern resistance. The data was obtained from two similar frigate type hull forms tested over a speed range from Fn=0.25 to 0.5. Five wave probes were used simultaneously to measure wave elevations and from these measurements five parallel estimates of wave pattern resistance were obtained. The elemental bias and precision error sources which are encountered are grouped and discussed according to three categories; calibration, data acquisition and analysis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Li, Xin, He Xu, Chen Yang, Haihang Wang y Fengshu Yu. "Study on an Underwater Flexible Manipulator Based on Hydraulic Drive". En BATH/ASME 2020 Symposium on Fluid Power and Motion Control. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/fpmc2020-2731.

Texto completo

Resumen

Abstract The underwater flexible robot is a field of continuous exploration and innovation. An underwater flexible manipulator with the functions of bending and grasping is presented in this paper, which is driven by the water hydraulic. The flexible manipulator is consisted mainly of three sets of transverse and three sets of longitudinal Mckibben artificial muscles (MAM) equidistantly arranged. The motions of the manipulator were driven by accurately controlling the length of each MAM that was changed by controlling the internal pressure, which was provided by the hydraulic power subsystem. The flexible manipulator was controlled remotely by the control subsystem. The inverse kinematics of the flexible manipulator was studied based on the neural network in this paper. The feasibility of the neural network inverse kinematics was proved by the data analysis. The three-dimensional virtual model of the flexible manipulator was projected into the captured real scene by the augmented reality (AR) technology to judge the bending degree of the manipulator operation, which could be seen in the experiment image.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Yildirim, Halid Can, Gary B. Marquis y Per J. Haagensen. "Experimental Verification of HFMI Treatment of Large Structures". En ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23764.

Texto completo

Resumen

Design recommendations for high frequency mechanical impact (HFMI)-treated welds have been proposed based on available experimental fatigue data of axially-loaded high strength steel specimens which include longitudinal, cruciform and butt welds. Test specimens were of a size appropriate for laboratory study. However, in reality, structures in civil, offshore and ship industries generally include large-scale and more complicated components, such as bridges, cranes, platforms, excavators etc. This paper presents a further validation of the design proposals by considering fatigue data sets which are obtained from large-scale components. The extracted fatigue data from the available literature includes bridge, crane and beam like components. In total, 65 published test results of weld details with various yield strengths (250 ≤ fy ≤ 725 MPa) and stress ratios (−1 ≤ R ≤ 0.56) are presented. All the data are found to be in good agreement with the previously-shown design curves.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Uluer, Pınar, Can Göçmenoğlu y Tankut Acarman. "Evaluation of Drivers Authority in a Structured Set of Driving Tasks and Decisions: Preliminary Results on Vehicle Simulator Study". En ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/esda2012-82675.

Texto completo

Resumen

One of the most challenging factors in the development of autonomous vehicles and advanced driver assistance systems is the imitation of an expert driver system which is the observer and interpreter of the technical system in the related driving scenario. To achieve an expert human-like situational understanding and decision making may be an important feature to fulfill the necessary active safety requirements. In this paper, an exploratory study on a multimodal adaptive driver assistance system is presented. The main goal is to determine the human driver’s attention and authority level in a cognitive model and to trigger the timely warnings according to his/her driving intents and driving skills with respect to the possible driving situation and hazard scenarios. In the previous studies, a fairly restrictive vision-based driver assistance system has been deployed to detect lane departure, blind-spot and to monitor following distance, headway time. This vision-based driver assistance system considers the driver’s driving performance metric sampled during the longitudinal and lateral vehicle control tasks as well as the processed information about the surrounding traffic environment consisting of the interactions with the other vehicles and the road situations. The presented active safety system models the driving task in a cognitive architecture and assesses the cognition of the human driver by modeling the situation awareness of the driver by using fuzzy sets. Each fuzzy set simply represents the expert driver’s perception in both of the longitudinal and lateral traffic. The presented system evaluates the driver’s driving skills and attention level by comparing the expert and human driver’s reactions suited in a finite set of decision and maneuvering task. In case of hazard analysis, the system triggers timely warnings pointing the driver’s attention at the lateral or longitudinal maneuvering tasks depending on the interpreted situation. Introductory experiments are performed with a limited number of participants, the test driving data including the driver’s perception and reaction to the surrounding vehicles and traffic situations are collected by the use of a vehicle simulator. And the presented multimodal adaptive driver assistance system is evaluated by the simulator. The preliminary results seem to be promising.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Gonzalez, Marco, Raul Machado y Jeanette Gonzalez. "Fatigue Analysis of PE-100 Pipe Under Axial Loading". En ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57631.

Texto completo

Resumen

In this paper, an experimental analysis for determining the fatigue strength of PE-100, one of the most used High Density Polyethylene (HDPE) materials for pipes, under cyclic axial loadings is presented. HDPE is a thermoplastic material used for piping systems, such as natural gas distribution systems, sewer systems and cold water systems, becoming in a good alternative to metals, as cast iron or carbon steel. One of the causes for failures of HDPE pipes is fatigue, due to pipes are under cyclic loading, such as internal pressure, weight loads or external loadings on buried pipes, which generate stress in different directions: circumferential, longitudinal and radial. HDPE pipes are fabricated using an extrusion process, which generates anisotropic properties. By testing in the Laboratory a series of identical specimens obtained directly from PE-100 HDPE pipes in longitudinal and circumferential directions, the relationships between amplitude stress and number of cycles (S-N curves) for two values of test frequency (2 and 5 Hz.) and stress ratio (R = 0.0 and R = 0.5), are established. For each case, three sets of survival probability data (90%, 50% and 10%) and coefficients of Basquin’s equation for the Ps = 50% curves, were obtained. The results obtained are in good agreement with the literature results, showing that stress direction in the pipe, tests frequency and stress ratio affect the fatigue strength of HDPE grade PE-100 pipes.

Los estilos APA, Harvard, Vancouver, ISO, etc.

McAuliffe, Brian. "A Drag-Reduction Prediction Model for Truck Platoons". En WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2024. http://dx.doi.org/10.4271/2024-01-2548.

Texto completo

Resumen

<div class="section abstract"><div class="htmlview paragraph">Truck platooning is an emerging technology that exploits the drag reduction experienced by bluff bodies moving together in close longitudinal proximity. The drag-reduction phenomenon is produced via two mechanisms: wake-effect drag reduction from leading vehicles, whereby a following vehicle operates in a region of lower apparent wind speed, thus reducing its drag; and base-drag reduction from following vehicles, whereby the high-pressure field forward of a closely-following vehicle will increase the base pressure of a leading vehicle, thus reducing its drag.</div><div class="htmlview paragraph">This paper presents a physics-guided empirical model for calculating the drag-reduction benefits from truck platooning. The model provides a general framework from which the drag reduction of any vehicle in a heterogeneous truck platoon can be calculated, based on its isolated-vehicle drag-coefficient performance and limited geometric considerations. The model is adapted from others that predict the influence of inter-vehicle distance for vehicle platoons, but extends the concept to account for cross winds and for lateral offsets between sequential vehicles, thus permitting its use for a range of modelling and simulation applications. Good agreement with experimental data sets from wind-tunnel and track tests is demonstrated in the paper.</div></div>

Los estilos APA, Harvard, Vancouver, ISO, etc.

Informes sobre el tema "Longitudinal data sets"

Younkman, Dianne D. Development of ROTC (Reserve Officers' Training Corps) Data Sets and Evaluation of Their Usefulness for Officer Longitudinal Research Data Base. Fort Belvoir, VA: Defense Technical Information Center, agosto de 1987. http://dx.doi.org/10.21236/ada189692.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Calderón Madrid, Angel. Revisiting the Employability Effects of Training Programs for the Unemployed in Developing Countries. Inter-American Development Bank, mayo de 2006. http://dx.doi.org/10.18235/0011237.

Texto completo

Resumen

Data sets used for evaluations in developing countries do not lend themselves to measuring the impact of training programs on the re-employment dynamics of trainees. An exception is a data set collected for an evaluation conducted in 1994 on participants in a training program targeting the unemployed in Mexico. In addition to having a control group of eligible individuals who did not participate in the program, this data set is the only one with longitudinal data covering not only the length of unemployment episodes after the training of the respondent, but also the duration of his/her employment spells. The authors show that a failure to distinguish between finding a "sustained" job versus finding "a job" can lead to misleading conclusions about a program's effectiveness. The authors also illustrate the need to correct for unobserved heterogeneity across individuals in hazard functions to avoid misleading implications in an evaluation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Milan, Lynn M. Analog Scales as Temperament Measures in the Baseline Officer Longitudinal Data Set (BOLDS). Fort Belvoir, VA: Defense Technical Information Center, marzo de 2002. http://dx.doi.org/10.21236/ada400570.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ramsey, Lori J. y Dianne D. Younkman. Development of the Automated Instructional Management System Data Set of the Officer Longitudinal Research Data Base. Fort Belvoir, VA: Defense Technical Information Center, enero de 1989. http://dx.doi.org/10.21236/ada207213.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Kimhi, Ayal, Barry Goodwin, Ashok Mishra, Avner Ahituv y Yoav Kislev. The dynamics of off-farm employment, farm size, and farm structure. United States Department of Agriculture, septiembre de 2006. http://dx.doi.org/10.32747/2006.7695877.bard.

Texto completo

Resumen

Objectives: (1) Preparing panel data sets for both the United States and Israel that contain a rich set of farm attributes, such as size, specialization, and output composition, and farmers’ characteristics such as off-farm employment status, education, and family composition. (2) Developing an empirical framework for the joint analysis of all the endogenous variables of interest in a dynamic setting. (3) Estimating simultaneous equations of the endogenous variables using the panel data sets from both countries. (4) Analyzing, using the empirical results, the possible effects of economic policies and institutional changes on the dynamics of the farm sector. An added objective is analyzing structural changes in farm sectors in additional countries. Background: Farm sectors in developed countries, including the U.S. and Israel, have experienced a sharp decline in their size and importance during the second half of the 20th century. The overall trend is towards fewer and larger farms that rely less on family labor. These structural changes have been a reaction to changes in technology, in government policies, and in market conditions: decreasing terms of trade, increasing alternative opportunities, and urbanization pressures. As these factors continue to change, so does the structure of the agricultural sector. Conclusions: We have shown that all major dimensions of structural changes in agriculture are closely interlinked. These include farm efficiency, farm scale, farm scope (diversification), and off-farm labor. We have also shown that these conclusions hold and perhaps even become stronger whenever dynamic aspects of structural adjustments are explicitly modeled using longitudinal data. While the results vary somewhat in the different applications, several common features are observed for both the U.S. and Israel. First, the trend towards the concentration of farm production in a smaller number of larger farm enterprises is likely to continue. Second, at the micro level, increased farm size is negatively associated with increased off-farm labor, with the causality going both ways. Third, the increase in farm size is mostly achieved by diversifying farm production into additional activities (crops or livestock). All these imply that the farm sector converges towards a bi-modal farm distribution, with some farms becoming commercial while the remaining farm households either exit farming altogether or continue producing but rely heavily on off-farm income. Implications: The primary scientific implication of this project is that one should not analyze a specific farm attribute in isolation. We have shown that controlling for the joint determination of the various farm and household attributes is crucial for obtaining meaningful empirical results. The policy implications are to some extent general but could be different in the two countries. The general implication is that farm policy is an important determinant of structural changes in the farm sector. For the U.S., we have shown the different effects of coupled and decoupled (direct) farm payments on the various farm attributes, and also shown that it is important to take into account the joint farm-household decisions in order to conduct a meaningful policy analysis. Only this kind of analysis explains the indirect effect of direct farm payments on farm production decisions. For Israel, we concluded that farm policy (or lack of farm policy) has contributed to the fast structural changes we observed over the last 25 years. The sharp change of direction in farm policy that started in the early 1980s has accelerated structural changes that could have been smoother otherwise. These accelerated structural changes most likely lead to welfare losses in rural areas.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Beal, Daniel. ESM Research: From Design and Analysis to Publication. Instats Inc., 2022. http://dx.doi.org/10.61700/cldz810mwahip469.

Texto completo

Resumen

This seminar introduces the use of Experience Sampling Methods (intensive longitudinal methods, ecological momentary assessment, diary methods, ambulatory assessment) to examine organizational phenomena. The first set of topics include development of ESM designs and measures, challenges with publishing ESM studies (with a particular emphasis on organizational journals), and an overview of tools used for ESM data collection and cleaning in R. The second set of topics focus on issues of ESM data analysis, including basic within- and between-person descriptive statistics and multilevel omega reliability from a Multilevel SEM perspective, and then more advanced Dynamic SEM techniques for causal inference in Mplus. An official Instats certificate of completion is provided at the conclusion of the seminar. For European PhD students, the seminar offers 2 ECTS Equivalent point.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Attanasio, Orazio P., Florencia Lopez Boo, Diana Perez-Lopez y Sarah Anne Reynolds. Inequality in the Early Years in LAC: A Comparative Study of Size, Persistence, and Policies. Inter-American Development Bank, diciembre de 2023. http://dx.doi.org/10.18235/0005359.

Texto completo

Resumen

Gaps in child development by socioeconomic status (SES) start early in life, are large and can increase inequalities later in life. We use recent national-level, cross-sectional and longitudinal data to examine inequalities in child development (namely, language, cognition, and socio-emotional skills) of children 0-5 in five Latin American countries (Chile, Colombia, Mexico, Peru and Uruguay). In the cross-section analysis, we find statistically significant gaps with inequality patterns that widely differ across countries. For instance, gaps in language and cognition for Uruguay and Chile are much smaller than those for Colombia and Peru. When turning to the longitudinal data, average SES gaps are similar to those of the cross-section in language but differ substantially in cognition, mainly in Uruguay where they emerge as more unequal when cohort effects do not operate. Importantly, we also find that the ECD gaps found at early ages (0-5), still manifest 6-12 years later in almost all locations and realms in which we have measures of early child development, but they do not increase with age. Results are robust to using different measures of inequality (income and maternal education). Gaps are smaller but generally remain when adjusting for possible explanatory factors (e.g., family structure, parental education, geographic fixed effects). To reduce ECD inequality and promote equality in later life outcomes, policymakers should look to implementing evidence-based interventions at scale to improve developmental outcomes of the most disadvantaged children in society.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Kiefner, J. F., J. M. Tuten y T. A. Wall. L51516 Preventing Pipeline Failure in Areas of Soil Movement - Part 1. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), enero de 1987. http://dx.doi.org/10.55274/r0010303.

Texto completo

Resumen

Ordinarily, buried pipelines undergo little or no movement in service. In a stable soil environment the longitudinal stress in a pipeline seldom approaches the limiting design value set by applicable codes and regulations. Pipeline serviceability under such conditions is seldom, if ever, threatened by the degree of longitudinal stress. In contrast, localized areas may exist along a pipeline where soils and/or slopes are unstable or where subsidence or differential settlement can occur. In these areas, longitudinal stresses may become severe enough to cause a failure. Over the years various techniques have been developed to monitor the status of pipelines in unstable areas, and various remedial techniques have been attempted. In more recent times, with the advent of Arctic and offshore pipelining, such potential movements of pipelines are being taken into account in the initial designs. In any case, there is a continuing need to develop better monitoring and remedial techniques to prevent pipeline failures in unstable soil areas. The objectives of this project are to develop a versatile and reliable prototype strain monitoring system, to demonstrate its applicability on an actual pipeline, and to establish allowable limits on strains due to soil movement or subsidence. The scope of the project includes:(1) Review of previous or on-going monitoring efforts by others.(2) Analysis of strains and development of models to predict strain behavior(3) Calculations to establish limits on strains(4) The design and construction of a microprocessor-controlled automatic monitoring system(5) The implementation of the system on an actual pipeline(6) The collection, analysis and interpretation of strain data from the system.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Wang. PGH376V A Comprehensive Update on the Evaluation of Pipeline Weld Defects. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), enero de 2008. http://dx.doi.org/10.55274/r0010920.

Texto completo

Resumen

Girth weld defect acceptance criteria are set and enforced in pipeline constructions per federal regulations (CFR 49 Parts 192 and 195). With the increased use of mechanized welding and AUT (Automated Ultrasonic Testing) in new pipeline constructions, alternative defect acceptance criteria based on ECA (Engineering Critical Assessment) principles are frequently used in lieu of the traditional workmanship criteria that are in the main body of API Standard 1104. Unfortunately, the current alternative defect acceptance criteria of API 1104 Appendix A has not been kept up-to-date with new linepipe materials, welding processes, and pipeline service environments. The objective of this project is to provide technical basis for updating the alternative girth weld defect acceptance criteria in API 1104 Appendix A and other similar codes and standards. There are two focus areas in this project. The first focus area is to update the alternative defect acceptance criteria to address the immediate need of pipeline constructions in the U.S., typically with pipeline longitudinal strains less than 0.5%, or alternatively termed stress-based design. The materials in the new constructions are typically of micro-alloyed type and the grades are moving higher, up to X80 and X100. These materials did not exist when the current API 1104 Appendix A was adopted. Their behavior is sufficiently different that a fresh look in the current environment is needed. The second focus area is to develop a set of procedures that may be used for determining the girth weld defect acceptance level under high longitudinal strains ( greater than 0.5% and up to 2-4%).

Los estilos APA, Harvard, Vancouver, ISO, etc.

Yunovich y Tossey. L52207 A Rapid Quality Assessment Method of Magnesium Anodes for Underground Pipeline Service. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), enero de 2008. http://dx.doi.org/10.55274/r0010960.

Texto completo

Resumen

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!