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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Evaluation of Post-Deployment PTSD Screening of Marines Returning From a Combat Deployment

Hall, Erika L. 01 January 2015 (has links)
The purpose of this quantitative study was to examine whether the post-deployment screening instrument currently utilized to assess active-duty Marines for symptoms of PTSD upon their return from a combat deployment can be solely relied upon to accurately assess for PTSD. Additionally, this study sought to compare the number of Marines who have sought trauma-related mental health treatment based on their answers on the Post-Deployment Health Assessment (PDHA) to the number who have sought trauma-related mental health treatment based on their answers on their PTSD Checklist â?? Military Version (PCL-M). The participants in this study were comprised of a sample of active-duty Marines that had recently returned from a combat deployment. A quantitative secondary data analysis used Item Response Theory (IRT) to examine the answers provided by the participants on both the PDHA and PCL-M. Both instruments proved to be effective when assessing symptoms of PTSD and the participants identified as having symptoms of PTSD were referred for mental health services as required. According to the results, more Marines were identified as having symptoms of PTSD using both assessment instruments (PDHA and PCL-M) compared to those identified using just the PDHA. The result was a better understanding of predictors of Marines who may later develop PTSD. The results of this study can also assist the Marine Corps with its post-deployment screening for symptoms of PTSD which in turn can provide appropriate mental health referrals for Marines if deemed appropriate.
262

Berufsbezogene Handlungs- vs. Lageorientierung: Skalierbarkeit und Beziehung zu beruflicher Arbeitsleistung / Occupational action state orientation: Scalability and its relation to job performance

Stadelmaier, Ulrich W. 12 December 2016 (has links) (PDF)
Die vorliegende Arbeit verknüpft die Theorie der Interaktion psychischer Systeme von Kuhl (2000, 2001) mit dem Modell beruflicher Arbeitsleistung von Tett und Burnett (2003). Unter Anwendung reizorientierter arbeitspsychologischer Stressmodelle werden Hypothesen über einen durch das subjektive Bedrohungs- und Belastungspotenzial der Arbeitssituation moderierten Zusammenhang zwischen dem berufsbezogenen und nach Maßgabe der Item Response Theorie skalierbaren Persönlichkeitsmerkmal Handlungs- vs. Lageorientierung und beruflicher Arbeitsleistung aufgestellt. In drei Befragungen an N = 415, N = 331 sowie N = 49 Berufstätigen wurden querschnittliche Daten zur Hypothesenprüfung erhoben. Berufsbezogene Handlungs- vs. Lageorientierung zeigt sich als valides Subkonstrukt der allgemeinen Handlungs- vs. Lageorientierung, welches gemäß Graded Response Modell von Samejima (1969, 1997) mit 14 Items skalierbar ist. Prospektive berufsbezogene Handlungs- vs. Lageorientierung erklärt in multiplen hierarchischen Regressionsanalysen, im Gegensatz zu allgemeiner Handlungs- vs. Lageorientierung, inkrementell zu Gewissenhaftigkeit, Extraversion und Neurotizismus Anteile kontextueller und aufgabenbezogener Arbeitsleistung. Hypothesenkonträr werden diese Zusammenhänge nur marginal vom subjektiven Belastungspotential der Arbeitssituation moderiert. Die Prädiktorfunktion prospektiver berufsbezogener Handlungs- vs. Lageorientierung für berufliche Arbeitsleistung bleibt auch unter pfadanalytischer Kontrolle eines vorhandenen Common Method Bias erhalten. Die dispositionelle Fähigkeit, durch berufliche Hindernisse gehemmten positiven Affekt vorbewusst gegenregulieren zu können, scheint demnach ein bedeutender Prädiktor beruflicher Arbeitsleistung zu sein, insbesondere bei Führungskräften. Für die berufliche Eignungsbeurteilung ist es damit von diagnostischem Mehrwert, Handlungs- vs. Lageorientierung kontextualisiert zu erheben. Der Einsatz probabilistisch- testtheoretisch konstruierter Skalen steigert dabei die Effizienz des Beurteilungsprozesses. / The current paper combines personality systems interaction theory (Kuhl, 2000, 2001) with the model of job performance by Tett and Burnett (2003). Using established stress models from work psychology it is hypothesized that there is a relation between occupational action state orientation, scalable by means of items response theory, and job performance, which is moderated by the subjective stress level of job characteristics. Three surveys among samples of N = 415, N = 331, and N = 49 professionals yielded cross sectional data for investigating the hypotheses. Occupational action state orientation proves a valid construct which is compatible with Samejima’s (1969, 1997) Graded Response Model using a 14-item scale. As a result of multiple hierarchical regression analyses, the hesitation dimension of specifically occupational, in contrast to general action state orientation is a predictor of both contextual and task performance, incremental to conscientiousness, extraversion, and neuroticism. Contrary to expectations this relation is only marginally moderated by stress-relevant job characteristics. Even when controlling for an occurring common method bias by means of path analysis the occupational hesitation dimension’s predictor role perseveres. Therefore, the dispositional ability in subconsciously regulating inhibited positive affect due to occupational obstacles, seems to be a crucial predictor of job performance, especially regarding leaders. Hence, professional aptitude assessment benefits from assessing action state orientation in a contextualized manner. Application of item response theory-based scales further enhances assessment process efficiency.
263

Teorie odpovědi na položku v kontextu sociologie / Teorie odpovědi na položku a její aplikace v sociologii

Rudá, Eliška January 2012 (has links)
The Item response Theory and its Application in the Sociology Abstract The focus of this master's thesis is an item response theory, a modern methodological approach, which models a relationship between a latent variable and measured responses to the particular item. A theoretical introduction, which explains fundamentals of the theory, is followed by a comparison with the classical test theory and suggestions of its possible applications in a field of sociology. The thesis is completed with an illustrative example using real data to evaluate an instrument for measuring subjective quality of working life in the framework of item response theory. Keywords: Item response theory, scale, reliability, model, subjective quality of working life
264

Počítačové adaptivní testování a možnosti jeho využití v psychodiagnostice / Computerized adaptive testing and its use in psychodiagnostic

Dlouhá, Jana January 2014 (has links)
5 Abstract The theoretical part of the paper focuses on computerized adaptive testing (CAT) and item response theory (IRT). Also included is a chapter comparing IRT with the commonly used classical test theory (CTT). There is also a brief mention of computerized and online testing, as these types of administration differ in many aspects from conventional paper & pencil tests. The goal of this paper was to evaluate the individual ways of eEPI test administration and to compare them with eEPQ tests and self-evaluation. In the practical part the items of the extraversion scale of the Eysenck Personality Inventory (eEPI) were calibrated using a group of 124 respondents. The acquired data were subsequently used to carry out a simulation of computerized adaptive testing, which clearly demonstrated the benefits of this type of testing in comparison to the classical test form. These results were compared with the results of real CAT test administration using the original sample and a new group of respondents (Np=69, Nn=68). The results were highly correlated with the results of the simulated test. Moreover, to verify the validity of the computerized adaptive version of eEOD, the respondents' results in this test were compared with the results in the eEPQ test and in a short self-assessment scale. Finally,...
265

[en] INFORMATION ASYMMETRY IN PRIVATE HEALTH INSURANCE CONTRACTS AND THE RELATIONSHIP BETWEEN MORBIDITY AND WORK MARKET: AN INVESTIGATION USING PNAD 2003 / [pt] ASSIMETRIA DE INFORMAÇÃO NA CONTRATAÇÃO DE PLANOS PRIVADOS DE SAÚDE E A RELAÇÃO ENTRE MORBIDADE DE MERCADO DE TRABALHO: UMA INVESTIGAÇÃO A PARTIR DA PNAD 2003

BERNARDO JOSÉ DE BRITO FERREIRA 22 July 2009 (has links)
[pt] Conhecer o perfil da população brasileira que possui planos privados de saúde é fundamental para orientar as políticas da Agência Nacional de Saúde (ANS) e a linha de ação das seguradoras e operadoras de saúde. A proposta deste projeto é de fazê-lo sob a ótica do mercado de trabalho, levando em consideração a morbidade auto-referida dos indivíduos, e controlando também pelas variáveis demográficas e sócio-econômicas. Para tanto, primeiramente, realizou-se um estudo exploratório relacionando a posse de planos de saúde com estas variáveis. Depois disso, ajustamos modelos logísticos de regressão para explicar as morbidades auto referidas a partir da situação do indivíduo no mercado de trabalho, controlando pelas variáveis demográficas. A mesma classe de modelos foi utilizada como ferramenta para investigar o fenômeno conhecido como Assimetria de Informação na contratação de planos privados de saúde. Os resultados concentram os casos de assimetria de informação em algumas doenças. Pudemos identificar também grupos de trabalhadores com alta propensão a determinadas doenças em determinadas grandes regiões do país. / [en] Knowing about the profile of the Brazilian population covered by private health plans is very important to guide the National Health Agency policies, the health insurance companies` action strategies in many ways and how the many agents involved should stand toward this process. Our purpose is to do this in the light of the work market situation, taking into account his/her self-reported morbidity, controlling for the demographical and social-economical variables. We start by presenting an exploratory study linking health plan owning with these variables. We then make use of logistic regression models, which have been adjusted to explain de self-reported morbidity according to the individual`s position in the job market, controlling for the demographical variables. The same class of model has also been used as a tool to investigate the existence of Information Asymmetry in this type of contract. Our results show that information asymmetry cases are concentrated in some diseases. We could also find some worker groups very likely to being ill from specific diseases in some specific regions of the country.
266

Aplicação da teoria de resposta ao item na análise de diferença de gênero de sintomas depressivos na população universitária brasileira / Using item response theory to analyze gender difference in depressive symptoms in Brazilian college students

Sá Júnior, Antônio Reis de 15 April 2019 (has links)
INTRODUÇÃO: Embora seja amplamente difundida a ideia de que não existem diferenças significativas entre homens e mulheres em termos dos sintomas que experimentam durante os episódios depressivos, pesquisas recentes sugerem que as diferenças sutis no perfil de sintomas podem existir e apontar para fundamentais diferenças de gênero na fisiopatologia dos estados depressivos. As mulheres são duas vezes mais propensas que os homens a sofrer de transtorno depressivo maior durante a sua vida e uma série de estudos têm indicado que as mulheres deprimidas tendem a apresentar mais sintomas depressivos \"atípicos\" e mais ansiedade e sintomas de somatização quando comparadas com os homens. Alguns dos problemas com as abordagens tradicionais para medir estas diferenças se devem às deficiências da teoria estatística subjacente dessas abordagens, como é o caso da teoria clássica dos testes (TCT). Nos últimos anos, o uso da teoria de resposta ao item (TRI) começou a substituir TCT na construção e avaliação de testes e alguns autores têm seguido com o uso de métodos baseados na TRI para estudar significativas variações clínicas individuais em vez dos métodos tradicionais baseados em escores totais. Um modelo para a TRI muitas vezes utilizado com a pontuação de itens politômicos é o modelo de resposta gradual (MRG). O MRG é adequado para a análise de escalas psicométricas com as categorias de resposta ordenadas e crescentes. O funcionamento diferencial dos itens da escala do Inventário de Depressão de Beck segunda versão (BDI-II) foi investigado, por gênero, comparando estes subgrupos de alunos MÉTODOS: Os 21 itens do BDI-II foram aplicados transversalmente em uma amostra representativa de 12.677 estudantes universitários brasileiros. A confiabilidade foi avaliada com base no coeficiente alfa de Cronbach. Os parâmetros gravidade (bi) e discriminação (a) de cada item do BDI-II foram calculados através do MRG. A influência do gênero foi testada para o funcionamento diferencial do item (DIF) dentro da abordagem baseada na TRI. RESULTADOS: O BDI-II apresentou boa confiabilidade (alfa = 0,91). As mulheres apresentaram significativamente maior probabilidade de depressão (ponto de corte > 13) do que os homens. Em geral, os participantes endossaram mais facilmente itens cognitivo-somáticos do que itens afetivos da escala. \"Sentimento de culpa\", \"ideias suicidas\" e \"perda de libido\" foram os itens que mais provavelmente indicaram maior gravidade da depressão (b3 >= 3,60). No entanto, todos os itens da BDI-II mostraram de moderada a alta discriminação (a >= 1,32) para o estado depressivo. Enquanto um item foi sinalizado como apresentando DIF, \"chorar\", com maior probabilidade das mulheres endossarem esse sintoma, o peso global desse item no escore total foi insignificante. CONCLUSÕES: Embora o gênero dos entrevistados possa apresentar influência no padrão de resposta dos sintomas depressivos, as medidas dos sintomas autorreferidos não inflacionaram os escores de gravidade. Esses achados fornecem suporte adicional à validade do uso do BDI-II para avaliar a depressão em contextos acadêmicos e destacam o valor de se considerar sintomas comuns de depressão relacionados ao sexo / INTRODUCTION: Although it is widely held that there are no significant differences between men and women in terms of the symptoms that they experience during depressive episodes, recent research suggests that subtle differences in symptom profile may exist and may point to fundamental gender differences in the pathophysiology of depressive states. Women are up to twice as likely as men to suffer from major depressive disorder during their lifetime and a number of studies have found that depressed females tend to exhibit more \'atypical\' depressive symptoms and more anxiety and somatization symptoms compared to men. Some of the problems with the traditional approaches to measure change are due to the shortcomings of the underlying statistical theory of these approaches, which is classical test theory (CTT). In recent years, the use of item response theory (IRT) has started to replace CTT in test construction and test evaluation and some authors have called for the use of IRT based methods to study individual clinical significant change instead of traditional methods based on total scores. An often-used IRT model for polytomous item scores is the graded response model (GRM). The GRM is suitable for analyzing psychometric scales with ordered and growing response categories. Potential differential item functioning of the scale items of the Beck Depression Inventory-II (BDI-II) is investigated, by gender, to compare across sub-groups of students. METHODS: The 21-item BDI-II was cross-sectionally administered to a representative sample of 12,677 Brazilian college students. Reliability was evaluated based on Cronbach\'s alpha coefficient. Severity (bi) and discrimination (a) parameters of each BDI-II items were calculated through the GRM. The influence of gender and age were tested for differential item functioning (DIF) within the IRT-based approach. RESULTS: The BDI-II presented good reliability (alpha = 0.91). Women significantly presented a higher likelihood of depression (cut-off > 13) than men. In general, participants endorsed more easily cognitive-somatic items than affective items of the scale. \"Guilty feelings\", \"suicidal thoughts\", and \"loss of interest in sex\" were the items that most likely indicated depression severity (b3 >= 3.60). However, all BDI-II items showed moderate-to-high discrimination (a >= 1.32) for depressive state. While one item was flagged for DIF, \"crying\", for gender, with women more likely endorsed this symptom than men, the global weight of this item on the total score was negligible. CONCLUSIONS: Although respondents\' gender might present influence on response pattern of depressive symptoms, the measures of self-reported symptoms have not inflated severity scores. These findings provide further support to the validity of using BDI-II for assessing depression in academic contexts and highlight the value of considering gender-related common symptoms of depression
267

Teoria e a prática de um teste adaptativo informatizado / Theory and practice of computerized adaptive testing

Sassi, Gilberto Pereira 10 April 2012 (has links)
O objetivo deste trabalho é apresentar os conceitos relacionados a Teste Adaptativo Informatizado, ou abreviadamente TAI, para o modelo logístico unidimensional da Teoria de Resposta ao Item. Utilizamos a abordagem bayesiana para a estimação do parâmetro de interesse, chamado de traço latente ou habilidade. Apresentamos os principais algoritmos de seleção de itens em TAI e realizamos estudos de simulação para comparar o desempenho deles. Para comparação, usamos aproximações numéricas para o Erro Quadrático Médio e para o Vício e também calculamos o tempo médio para o TAI selecionar um item. Além disso, apresentamos como instalar e usar a implementação de TAI desenvolvida neste projeto chamada de TAI2U, que foi desenvolvido no VBA-Excel usando uma interface com o R / The main of this work is to introduce the subjects related to Computerized Adaptive Testing, or breafly CAT, for the unidimensional three-parameter logistic model of Item Response Theory. We use bayesian approach to estimate the parameter of interest. We present several item selection algorithms and we perform simulations comparing them. The comparisons are made in terms of the mean square error, bias of the trait estimates, the average time for item selection and the average length of test. Furthermore, we show how to install e use the CAT implementation of this work called built in MIcrosoft Excel - VBA using interface with the statistical package R
268

Teste adaptativo computadorizado nas avaliações educacionais e psicológicas / Computerized adaptative test in educational and psychological evaluation

Ricarte, Thales Akira Matsumoto 04 April 2013 (has links)
Testes Adaptativos Computadorizados (TAC) são aqueles que selecionam gradativamente as questões (itens) a serem apresentadas ao indivíduo de acordo com o seu nível de conhecimento (traco latente). Um TAC pode se basear em um modelo da Teoria da Resposta ao Item (TRI) para a estimação do traco latente e escolha do item a ser apresentado em cada passo do teste. Este trabalho apresenta modelos da TRI utilizados em TAC encontrados na literatura e descreve alguns métodos de calibração de itens para a formação e manutenção do banco de questões do teste sob o modelo de Samejima (1969), estimação do traço latente, seleção de itens com restrições utilizando a abordagem Shadow test e critérios de parada normalmente utilizados. Foram realizadas simulações com um banco grande (500 itens) e com um banco pequeno (21 itens) e avaliada a qualidade das estimativas dos traços latente (através do cálculos dos vícios e erros quadráticos médios) de TACs com diferentes números de itens. Foi aplicado o modelo de Samejima às respostas de estudantes do Exame ao proficiência em inglês (EPI) do ICMC - USP, que é aplicado semestralmente no formato lápis e papel, para a formação de um banco de itens e posterior construção de um TAC. Também foi aplicado o modelo às respostas de pacientes clínicos do Hospital das Clínicas da Medicina da USP, cedido pelo doutor Yuang-Pang Wang, ao Inventário de Depressão de Beck (BDI) para os mesmos propósitos. Comparações com a atual metodologia para avaliação da proficiência em língua inglesa do EPI (Medida de Probabilidade Admissível, MPA) e para o diagnóstico de depressão do BDI (critério sugerido por Kendall et al., 1987) foram realizadas demonstrando as vantagens e maior riqueza dos resultados obtidos com a TRI e com os TACs implementados. Adcionalmente foi desenvolvido um programa Same-CAT que armazena bancos de itens e possibilita a criação e aplicação de TACs com restrições, através da abordagem Shadow test / Computerized Adaptive Tests (CAT) are those that select questions (items) gradually to be presented to an individual according to their proficiency (latent trait level). A CAT can be based on an Item Response Theory (IRT) model for estimation of the latent trait and selection of the next item to be presented in each step of the test. This paper presents IRT models used in CATs found in literature and describes some methods of item calibration for creation and maintenance of a test items bank under the Samejima\'s model (Samejima; 1969), estimation of latent trait, item selection with constraints using the Shadow test approach and usuals stopping criteria. Simulations were conducted with a large bank (500 items) and a small bank (21 items) and the quality of the estimatives of latent traits were evaluated (through calculations of mean squared errors and bias) TACs with different item numbers. Samejima\'s model were applied for the responses of students to the English Proficiency Exam (EPE) of ICMC - USP, a test applied twice a year in paper and pencil format, to create an item bank and subsequent construction of a CAT. The model was also applied to the responses of clinical patients from the Hospital das Clnicas - USP, given by Dr. Yuang-Pang Wang, to the Beck Depression Inventory (BDI) for the same purposes. Comparisons using the current methodology to evaluate the English Language Proficiency of EPE (Measure of Probability Allowable, MPA) and the BDI (criterion suggested by Kendall et al., 1987) were performed, and the CATs provided better and richer results. Furthermore a program, Same-CAT, that stores item banks and allows CAT\'s applications with constraints was created
269

Neue Methoden zur Entdeckung von Fehlspezifikation bei Latent-Trait-Modellen der Veränderungsmessung

Klein, Stefan 09 May 2003 (has links)
Ziel der Arbeit ist die Entwicklung von Modellen zur Entdeckung von Fehlspezifikation im Linear Logistic Test Model ( = LLTM) und verwandten Modellen der Verände\-rungs\-mes\-sung. Fehlspezifikation bedeutet hierbei, dass dem Modell ein unzutreffendes Muster latenter Traits zugrundegelegt wurde. Dies kann, vgl. z.B. [Baker,1993], zu bedeutenden Schätzfehlern führen. Die hier vorgestellten Methoden ermöglichen es unter leicht zu erfüllenden Annahmen, Aussagen über das Ausmaß der Unkorrektheit der verwendeten Modellspezifikation zu machen, ohne die in der Modellschätzung bestimmten Parameterwerte verwenden zu müssen. Zunächst wird eine auf dem Mantel-Haenszel-Test beruhende Methodik vorgestellt, die bei Tests bezüglich der Veränderungsparameter eines LLTMs als direkte Konkurrenz zu den bekannten Likelihood-Ratio-Tests für das LLTM anzusehen ist, wie sie z.B. bei [Fischer,1995a] vorgestellt werden. Weiterhin werden für das LLTM optimierte Personenfittests und daraus abgeleitete Effektgrößen vorgestellt. Diese ermöglichen das Auffinden von Subpopulationen, bei denen eine Abweichung zum angenommenen Modell aufgetreten ist. Es werden die statistischen Eigenschaften dieser Tests resp. Effektgrößen mittels Simulation und Teststärkeberechnung untersucht und Anwendungsbeispiele für diese Methoden vorgestellt. / In this thesis, new methods are developed for the detection of misspecification within Linear Logistic Test Models (=LLTM) and similar model classes for the measurement of change. The phrase "misspecification" will be used if a wrong selection of latent traits is chosen for the estimation of the LLTM. Misspecification can lead to erronious estimation [Baker,1993]). Using the newly developed methods, it is possible to measure the extent of deviations between the proposed model and the data. This can be done without using estimated parameter values. First a method is introduced which is based on the well-known Mantel-Haenszel-test. For some hypotheses, this method can be used instead of a Likelihood Ratio Test (e.g. [Fischer,1995a]). The Main topic of this thesis are uniformly most powerful tests for the measurement of person fit and related effect measures. These effect measures can be used for the identification of subpopulations where the proposed model does not hold. Statistical properties of these tests resp. effect measures are examined by simulations and power calculations using the SAS software. Furthermore, examples of the application of these methods are given.
270

Modelos multidimensionais da teoria de resposta ao item / Multidimensional models of item response theory

Tiago de Miranda Fragoso 04 August 2010 (has links)
Avaliaçõs educacionais, de distúrbios psicológicos e da aceitação de um produto no mercado são exemplos de estudos que buscam quantificar um construto de interesse através de questionários compostos por itens de múltipla escolha. A Teoria de Resposta ao Item (TRI) é muito utilizada na análise de dados provenientes da aplicação desses questionários. Há vários modelos da TRI já muito utilizados na prática com tal finalidade, tanto para respostas dicotômicas aos itens (certo/errado, presente/ausente, sim/não), quanto para itens com mais de duas categorias de resposta (nominais ou ordinais). No entanto, a grande maioria supôe que apenas um traço latente é necessário para explicar a probabilidade de resposta ao item (modelos unidimensionais). Como as situações práticas são usualmente caracterizadas por várias aptidões (traços latentes) influenciando a probabilidade de um indivíduo apresentar certa resposta ao item, os modelos multidimensionais são de grande importância. Neste trabalho, após um levantamento bibliográfico dos principais modelos multidimensionais da TRI existentes na literatura, realizou-se um estudo detalhado de um deles: o modelo logístico multidimensional de dois parâmetros. O método de estimação dos parâmetros dos itens por máxima verossimilhança marginal e dos traços latentes por máxima verossimilhança são explicitados assim como a estimação por métodos bayesianos. Todos os métodos foram implementados em R, comparados e aplicados a um conjunto de dados reais para avaliação do Inventário de Depressão de Beck (BDI) e do Exame Nacional do Ensino Médio (ENEM) / Educational evaluations, psychological testing and market surveys are examples of studies aiming to quantify an underlying construct of interest through multiple choice item tests. Item Response Theory (IRT) is a class of models used to analyse such data. There are several IRT models already being used in applied studies to such end, either for dichotomical answers (right/wrong, present/ absent, Yes/No) or for itens with nominal or ordinal answers. However, the large majority of those models make the assumption that only one latent trait is sufficient to explain the probability of a correct answer to an item (unidimensional models). Since many situations in practice are characterized by multiple aptitudes (latent traits) in uencing such probabilities, multidimensional models that take such traits into consideration gain great importance. In the present work, after a thorough review of the litterature regarding multidimensional IRT models, we studied in depth one model: the two parameter multidimensional logistic model for dichotomical items. The marginal maximum likelihood method used to estimate the item parameters and the maximum likelihood method used for the latent traits as well as bayesian methods for parameter estimation were studied, compared, implemented in the R software and then applied to a real dataset to infere depression using the Beck Depression Inventory(BDI)and the Exame Nacional do Ensino Médio (ENEM)

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