Latent Class Models

Bioarchaeological Investigations of health and demography in Medieval Asturias, Spain

by Nicholas Passalacqua

Dissertation

The purpose of this study is to investigate the impact of political and economic change on the health of people living... more The purpose of this study is to investigate the impact of political and economic change on the health of people living in predominantly rural communities of Medieval Asturias, Spain from
~900-1800 AD. This project examines the remains of ~325 individuals recovered from 12 Medieval Christian church cemeteries located within the historically and politically defined
boundaries of Asturias, Spain.

Iberia has a rich written history beginning with the first Romans to enter the peninsula and describe the peoples they encountered (Collins 2000). This history became more detailed as time progressed with multiple histories of events being recorded in the Medieval Period by different parties (Linehan 1993). Unfortunately, as is common in Medieval histories, these documents concern only the key individuals involved in large political events. The average individual has no written history, nor is there an anecdotal summary of what peasant life was like in Medieval Asturias. Due to this dearth of information, this dissertation takes a historical bioarchaeology approach using what information is available from the historical narrative relating to Medieval Asturias, in order to approach issues of the economy, inferred gender, and familial status roles and their relationship to pathological markers found in the human skeletal
remains of this population.

Due to the often rushed nature of salvage archaeological methods, much contextual evidence was lost during excavation of many of these sites. Further the acidic mountainous soils of Asturias often result in poorly preserved skeletal material. Here these pitfalls will be addressed using two unique approaches: (1) this project will examine life histories of the general rural population of Medieval Asturias at the regional level. This will be achieved by aggregating all individuals from the available archaeological sites, and directing hypotheses at regularities at
the regional scale. (2) In order to tackle the issue of poor or differential preservation of human remains, this project will employ new maximum likelihood statistical procedures specifically
designed to handle missing data and generate probability statements. It should be noted that while the robust statistical approaches taken here will focus on region-level analyses, they could also be applied to large well documented sites in future investigations.

Results demonstrate that while historians (e.g. Kamen 1991; Lynch 1992; Ortiz 1971; Ruiz 2007) suggest rampant collapse and crisis throughout much of the later Medieval and Spanish Empire periods, the biology of the individuals from the same time shows no record of significant increases in stress or disease. Many other scholars (e.g. Bennett 2005; Miller 2003; Lopez et al. 2012) suggest the patriarchal nature of Medieval and Imperial Spain resulted in negative health outcomes for females in comparison to their male counterparts, but this is again not detected in the present examination of the skeletal biology. Finally, historians (e.g. Bango Toviso 1992) and mortuary anthropologists (e.g. Naji 2005; Ivison 1993; Effros 1997) alike argue that the practice of ad sanctos burial favored those high status individuals who were most regarded in the community, for prestigious burial locations within churches, but these results found no significant differences in terms of mortality (risk of dying at younger ages) or the development of physiological stress markers.

Assessing reliability of categorical substance use measures with latent class analysis

by Brian Flaherty

Using Data Augmentation to Obtain Standard Errors and Conduct Hypothesis Tests in Latent Class and Latent Transition Analysis

by Brian Flaherty

Cross-National and Cross-Ethnic Differences in Attitudes: A Case of Luxembourg

by Miloš Kankaraš

Kankaraš, M. & Moors, G. (in press). Cross-National and Cross-Ethnic Differences in Political and Leisure Attitudes. A Case of Luxemburg. Cross-Cultural Research, Sage.

Minorities’ attitudes can be compared to attitudes of fellow citizen within the host country as well as to attitudes... more Minorities’ attitudes can be compared to attitudes of fellow citizen within the host country as well as to attitudes of the motherland. Given the heterogeneity of Luxembourg’s minority groups, this country is a relevant example case in which the comparison needs to involve answering a two-folded question. First we analyze the level of measurement equivalence, i.e. the extent to which different groups can be compared. Secondly, we examine whether ethnic-cultural groups within Luxembourg resemble citizens from their native country more than their country of residence. Using EVS-data from 2008 we demonstrate different types of outcomes. Results indicate that cultural background is more important than national context in the case of culturally more distant minorities to Luxembourg’s resident population, and that national setting is the prevailing factor when minorities are from neighboring countries. The effect of a common national setting is also important with regards to the issue of measurement equivalence, where it contributes to greater comparability of intra-national, cross-ethnic comparisons.

The heterogeneity in shipper value of time: results from an SP experiments using mixed logit and latent class

by marcucci edoardo

Two‐year predictive validity of conduct disorder subtypes in early adolescence: a latent class analysis of a Canadian longitudinal sample

by Eric Lacourse

Use and validation of the Short Inventory to Monitor Psychosocial Hazards at the workplace

by Guy Notelaers

European Conference of Psychology, Oslo, 2009

Measuring exposure to bullying and harassment at work: Validity, factor structure and psychometric properties of the Negative Acts Questionnaire-Revised

by Guy Notelaers

Staale Einarsen, Helge Hoel and Guy Notelaers in Work & Stress, 2009.

This study investigates the psychometric properties, factor structure and validity of the revised Negative Acts ... more This study investigates the psychometric properties, factor structure and validity of the revised Negative Acts  Auestionnaire-Revised (NAQ-R), an instrument designed to measure exposure to bullying in the workplace. By reanalyzing data based on a heterogeneous sample of 5288 UK employees, the results show that the 22-item instrument has a high internal stability,with three underlying factors: personal bullying, work-related bullying and physically intimidating
forms of bullying, although the instrument may also be used as a single factor measure. Criterion validity was explored by relating the scores on the NAQ-R to a single-item measure of perceived victimization from bullying, showing high correlations with both the total NAQ-R and scores on the three factors. Targets of bullying scored significantly higher on
all 22 items compared to non-targets. The NAQ-R correlated as expected with measures of mental health, psychosocial work environment and leadership, indicating a good construct
validity of the instrument. Furthermore, a latent class cluster (LCC) analysis showed that the instrument may be used to differentiate between groups of employees with different levels of exposure to bullying, ranging from infrequent exposure to incivility at work to severe victimization from bullying and harassment. The more commonly used operational criteria can also be used to detect targets of bullying. Hence, the NAQ-R is proposed as a standardized
and valid instrument for the measurement of workplace bullying.

Advances in Stated Preference Methods: Discrete and continuous Mixing distributions in Logit models for representing variance and taste heterogeneity.

by Marco Boeri

My thesis for The Degree of Doctor of Philosophy
Main supervisor: Alberto Longo; other supervisors Danny Campbell and George Hutchinson.

Public policies should reflect and accommodate as much as possible citizens’ preferences and values. However, it is... more Public policies should reflect and accommodate as much as possible citizens’ preferences and values. However, it is dicult to know the correct value citizens place on public goods as they are not generally exchanged in the marketplace. For this reason,
non market valuation is increasingly considered to be an important tool for informing policy decisions. In this context, Contingent Valuation (CV) and Discrete Choice Experiments (DCE) are probably the most widely used tools to analyse Stated preferences and retrieve people’s Willingness to Pay (WTP) for improving a particular environmental amenity. Since its introduction as a technique of non-market valuation, the number of CV studies published in peer reviewed journals consistently increased for more than three decades. Then, since the mid to late 1990s, the CV technique has been largely substituted by the DCE method.

Having reviewed the literature, it was decided to focus my Phd on DCE method. Notwithstanding the importance of CV as a useful tool for preference elicitation, DCE proved more appealing, as recent literature have identified a number of exciting research
avenues from a methodological and econometric point of view.
Therefore, the PhD has been mainly focused on developing new tools for accommodating heterogeneity in tastes, variances and heuristics employing Latent Class (LC) analysis. As a result, I formalised a class of LC models that can accommodate heteroscedasticity and/or heterogeneity (depending on assumptions and parameterisation) within each class as well as dierent heuristics across classes. The three essays collected
in this thesis represent the main outcome of this research.

More specifically the first paper, on urban land use, introduces class heterogeneity within a LC model. This is obtained by specifying a discrete mixture of sets of continuous distributions. The model is applied to both simulated and real data in order to
demonstrate its flexibility and the advantages for policy appraisal.

The second paper introduces and formalises the idea of a heteroscedastic LC model using data from a recreational site choice study elicited through stated preference methods
to compare various model specifications. Results show that model fit, welfare estimates and choice predictions are sensitive to the manner in which both types of heterogeneity are accommodated for. This is done in WTP-space to directly compare estimates from continuous and discrete mixture representations as well as to demonstrate the importance of including the scale parameter even under this reparameterisation.

In the third and final paper, on species preservation, the well known problem of preference and variance instability due to learning and fatigue in DCE is tackled by applying a scale-adjusted latent class model to uncover both types of instability simultaneously and probabilistically across the sample. Findings highlight the advantages, in terms of model fit, interpretation and policy implications, that can be achieved when both types
of instability are addressed concurrently. Data collected to estimate the existence value of rare and endangered fish species in Ireland are utilised as an empirical case-study.

Finally conclusions and avenues for possible further research and future applications
of the presented models are drawn.

Special topics in the inclusion of covariates and distal outcomes in finite mixture and latent class models

by Elián Cabrera-Nguyen

Masyn,K., Nylund-Gibson,K., Cabrera-Nguyen, E. P.,Peña, J.B. (2012, February 11). Special topics in the inclusion of covariates and distal outcomes in finite mixture and latent class models. Symposium to be conducted at the meeting of the Society for Research in Child Development, Developmental Methodology Section, Tampa, FL.

Presenting authors: Masyn,K., Nylund-Gibson,K., Cabrera-Nguyen, E. P.

Teacher Efficacy as a Multigroup Model Using Latent Class Analysis

by Donald Easton-Brooks

Autism symptoms in attention-deficit/hyperactivity disorder: a familial trait which correlates with conduct, oppositional defiant, language and motor disorders

by Richard Anney

Mulligan A, Anney RJ, O'Regan M, Chen W, Butler L, Fitzgerald M, Buitelaar J, Steinhausen HC, Rothenberger A, Minderaa R, Nijmeijer J, Hoekstra PJ, Oades RD, Roeyers H, Buschgens C, Christiansen H, Franke B, Gabriels I, Hartman C, Kuntsi J, Marco R, Meidad S, Mueller U, Psychogiou L, Rommelse N, Thompson M, Uebel H, Banaschewski T, Ebstein R, Eisenberg J, Manor I, Miranda A, Mulas F, Sergeant J, Sonuga-Barke E, Asherson P, Faraone SV, Gill M. Autism symptoms in Attention-Deficit/Hyperactivity Disorder: a familial trait which correlates with conduct, oppositional defiant, language and motor disorders. J Autism Dev Disord. 2009 Feb;39(2):197-209. Epub 2008 Jul 19. Erratum in: J Autism Dev Disord. 2009 Feb;39(2):210-1. PubMed PMID: 18642069.

U.S. Cultural Involvement and its Association with Co-Occurring Substance Abuse and Sexual Risk Behaviors among Youth in the Dominican Republic: A Latent Class Regression Analysis

by Elián Cabrera-Nguyen

Authors: Cabrera-Nguyen, E. P., & Peña, J.B.

Cabrera-Nguyen was presenting author

We examined the relationship of US cultural involvement with substance abuse and sexual risk behavior profiles in a... more We examined the relationship of US cultural involvement with substance abuse and sexual risk behavior profiles in a nationally representative sample of public high school students in the Dominican Republic using latent class analysis. Using a novel methodological approach, we examined explanations for the so-called Latino or Hispanic immigrant paradox while controlling for selection bias. US cultural involvement indicators were independent and robust predictors of increased substance abuse and sexual risk behaviors after adjusting for sociodemographic covariates. Implications for prevention efforts targeting risk behaviors among Latino/a adolescents in the US and abroad are considered.

From Natural Language Software Specifications to UML Class Models

by Imran Sarwar Bajwa

Lecture Notes in Business Information Processing, Springer

Software specifications are typically captured in natural languages and then software analysts manually analyzed and... more Software specifications are typically captured in natural languages and then software analysts manually analyzed and produce the software models such class models. Various approaches, frameworks and tool have been presented for automatic translation of software models such as CM-Builder, Re-Builder, NL-OOML, GOOAL, etc. However, the experiments with these tools show that they do not provide with high accuracy in translation. Major reason of less accuracy reported in the literature is the ambiguous and informal nature of the natural languages. In this article, we aim to address this issue and present a better approach for processing natural languages and produce more accurate UML software models. The presented approach is based on Semantic Business Vocabulary and Rules (SBVR) recently adopted standard by OMG. Our approach works as the natural language software specifications are first mapped to SBVR rules representation. SBVR rules are easy to translate other formal representations such as OCL and UML as SBVR is based on higher order logic. A case study solved with our tool NL2UMLviaSBVR is also presented and the a comparative analysis of our tools research with other available tools show that use of SBVR in NL to UML translation helps to improve the accuracy.

¿Ineficiencia o diferencias tecnológicas en el sector lechero?

by Julio del Corral

published in Revista de Economía Aplicada, 2008

Identification of Segments of Soccer Clubs in the Spanish League First Division with a Latent Class Model

by Julio del Corral

published in Journal of Sports Economics, 2008

Identifying Different Technologies using a Latent Class Model: Extensive versus Intensive Dairy Farms

by Julio del Corral

published in European Review of Agricultural Economics, 2010

Latent mixture models for multivariate and longitudinal outcomes

by Tim Croudace

Biased mentalizing in children aged seven to 11: Latent class confirmation of response styles to social scenarios and associations with psychopathology

by Tim Croudace

Improvements in social functioning reported by a birth cohort in mid-adult life: a person-centred analysis of GHQ-28 social dysfunction items using latent class analysis

by Tim Croudace