Submitted by (edna.saturno@ufrpe.br) on 2017-02-07T12:40:31Z No. of bitstreams: 1 Ana Lia Camposa Quaggio.pdf: 1430515 bytes, checksum: 68e33f51877fa5eba2d7e0997b3e6520 (MD5) / Made available in DSpace on 2017-02-07T12:40:31Z (GMT). No. of bitstreams: 1 Ana Lia Camposa Quaggio.pdf: 1430515 bytes, checksum: 68e33f51877fa5eba2d7e0997b3e6520 (MD5) Previous issue date: 2010-02-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Since the 50’s, Xiphias gladius (Linnaeus, 1758) has been captured along the Brazilian coast by surface longliners. This is the second most important target species for the tuna fleet based in Itajaí, Santa Catarina State, after the blue-shark, Prionace glauca (Linnaeus, 1758). The study was based on data from sea observers, log books and carcass ladings of Xiphias gladius, Linnaeus, 1758) from the pelagic longline fleet based in Itajaí, which operated in the southwest Atlantic. Covariance models were fit to the catches (weight, kg) of swordfish and the effects used were: (1) the years 1997, 1998, 2001, 2002 e 2007 (2) lunar phases and (3) seasons. The covariate was fishing effort (hooks). The highest moon catches occurred on the first quarter moon and during wintertime. The Mantel-Haenszel procedure was used to test the hook selectivity and showed that the type “J” hook (J 9/0 10º offset), traditionally used by the fleet, have 1.2 more chances of catching Xiphias gladius than the “circle” hook (18/0 10º offset), used as an optinal device to reduce sea turtle bycatch. The M-H test showed that the J hook has 1,2 more chances of catching Xiphias gladius than the circle hook. The conversion of individual carcass weights (kg) to total length (cm) for the years 2000 to 2002 showed that 66% of the catches were sub-adults. / O espadarte, Xiphias gladius (Linnaeus, 1758), vem sendo capturado na costa brasileira desde os anos 50 pelo espinhel-de-superfície. Esta é a segunda mais importante espécie-alvo da frota atuneira sediada em Itajaí (SC), ficando atrás apenas do tubarão-azul, Prionace glauca (Linnaeus, 1758). No presente estudo foram analisados os dados obtidos para esta espécie através de observadores, mapas de bordo e fichas de desembarque de carcaças de X. gladius para a frota de espinhel-de-superfície sediada em Itajaí (SC) e atuante no Atlântico sudoeste. Foram elaborados modelos de análise de covariância (ANCOVA) e aplicados aos dados de captura (peso em kg) do espadarte, tendo como efeitos: (1) os anos de 1997, 1998, 2001, 2002 e 2007 (2) as fases lunares e (3) as épocas do ano. A covariável foi o esforço de pesca (n° de anzóis). As maiores médias de captura ocorreram durante as fases de lua crescente e no inverno. O procedimento estatístico de Mantel-Haenszel teste foi utilizado para comparar as capturas do espadarte no anzol tipo “Jota” (9/0 10º offset) comumente utilizado pela frota espinheleira com o anzol tipo “circular” (18/0 10ºoffset), este último oferecido como alternativa mitigadora à captura de tartarugas marinhas. O teste M-H indicou que o anzol “Jota” apresentou 1,2 mais chances de capturar Xiphias gladius que no “circular”. A conversão dos pesos individuais das carcaças (kg) em comprimentos totais (cm), referentes aos anos de 2000 a 2002, indicou que 66% das capturas foram de sub-adultos, ao longo de todo o ano.

Purpose: Asthma can have significant adverse effects on the health and quality of life of children, and the prevalence of this condition continues to rise. Breastfeeding may protect against asthma, but some uncertainty remains. The purpose of this study was to further examine the relationship between breastfeeding and the risk of developing asthma in early childhood. Methods: Data were collected from the State and Local Area Integrated Telephone Survey: National Survey of Children's Health, 2003. The study population consisted of 33,315 children ages 0 to 5 years. Prevalence rates of asthma and breastfeeding ,were calculated, as were crude and Mantel-Haenszel summary odds ratios for breastfeeding and other potential confounders including age, race, education, poverty, and tobacco use. Logistic regression models were used to estimate odds ratios and 95% confidence intervals aRer adjustment for these confounders. Results: Breastfeeding (never vs. ever) was significantly associated with an increased odds ratio of asthma among the children surveyed (POR = 1.18, 95% CI = 1.04, 1.34). In addition, children with asthma had a slightly lower mean duration of breastfeeding than did children without asthma. However, a significant trend of increasing odds ratios with increasing duration of breastfeeding was not found. It therefore appears that the act of ever breastfeeding, regardless of duration, exerts some protective effect against the development of asthma in early childhood. Conclusions: Never breastfeeding was found to be significantly associated with the development of asthma in early childhood. Age, race, education, poverty level, and tobacco use were also implicated in this association. While further research is needed to fully determine the effectiveness of breastfeeding in the primary prevention of asthma, public health efforts should focus on promoting breastfeeding as it has the potential improve the overall health of children.

Differential item functioning (DIF) occurs when individuals from different groups who have equal levels of a latent trait fail to earn commensurate scores on a testing instrument. Type I error occurs when DIF-detection methods result in unbiased items being excluded from the test while a Type II error occurs when biased items remain on the test after DIF-detection methods have been employed. Both errors create potential issues of injustice amongst examinees and can result in costly and protracted legal action. The purpose of this research was to evaluate two methods for detecting DIF: logistic regression (LR) and Mantel-Haenszel (MH). To accomplish this, meta-analysis was employed to summarize Monte Carlo quantitative studies that used these methods in published and unpublished literature. The criteria employed for comparing these two methods were Type I error rates, the Type I error proportion, which was also the Type I error effect size measure, deviation scores, and power rates. Monte Carlo simulation studies meeting inclusion criteria, with typically 15 Type I error effect sizes per study, were compared to assess how the LR and MH statistical methods function to detect DIF. Studied variables included DIF magnitude, nature of DIF (uniform or non-uniform), number of DIF items, and test length. I found that MH was better at Type I error control while LR was better at controlling Type II error. This study also provides a valuable summary of existing DIF methods and a summary of the types of variables that have been manipulated in DIF simulation studies with LR and MH. Consequently, this meta-analysis can serve as a resource for practitioners to help them choose between LR and MH for DIF detection with regard to Type I and Type II error control, and can provide insight for parameter selection in the design of future Monte Carlo DIF studies.

This dissertation served two purposes. The first was to develop a method of detecting differential item functioning (DIF) within tests containing both dichotomously and polytomously scored items. The second was related to gender and aimed a) to investigate if those items that were functioning differently for girls and boys showed any characteristic properties and, if so, b) determine if these properties could be used to predict which items would be flagged for D1F. The method development was based on the Mantel-Haenszel (MH) method used for dichotmously scored items. By dichotomizing the polytomously scored items both types of item could be compared on the same statistical level as either solved or non-solved items. It was not possible to compare the internal score structures for the two gender groups, only overall score differences were detected. By modelling the empirical item characteristic curves it was possible to develop a MH method for identifying nonuniform DIF. Both internal and external ability criteria were used. Total test score with no purification was used as the internal criterion. Purification was not done for validity reasons, no items were judged as biased. Teacher set marks were used as external criteria. The marking scale had to be transformed for either boys or girls since a comparison of scores for boys and girls with the same marks showed that boys always got higher mean scores. The results of the two MH analyses based on internal and external criterion were compared with results from P-SIBTEST. All three methods corresponded well although P-SIBTEST flagged considerably more items in favour of the reference group (boys) which exhibited a higher overall ability. All 200 items included in the last 15 annual national tests in physics were analysed for DIF and classified by ten criteria The most significant result was that items in electricity were, to a significantly higher degree, flagged as DIF in favour of girls whilst items in mechanics were flagged in favour of boys. Items in other content areas showed no significant pattern. Multiple-Choice items were flagged in favour of boys. Regardless of the degree of significance by which items from different content areas were flagged on a group level it was not possible to predict which single item would be flagged for DIF. The most probable prediction was always that an item was neutral. Some possible interpretations of DIF as an effect of multidimen-sionality were discussed as were some hypotheses about the reasons why boys did better in mechanics and girls in electricity. / digitalisering@umu

abstract: The study examined how ATFIND, Mantel-Haenszel, SIBTEST, and Crossing SIBTEST function when items in the dataset are modelled to differentially advantage a lower ability focal group over a higher ability reference group. The primary purpose of the study was to examine ATFIND's usefulness as a valid subtest selection tool, but it also explored the influence of DIF items, item difficulty, and presence of multiple examinee populations with different ability distributions on both its selection of the assessment test (AT) and partitioning test (PT) lists and on all three differential item functioning (DIF) analysis procedures. The results of SIBTEST were also combined with those of Crossing SIBTEST, as might be done in practice. ATFIND was found to be a less-than-effective matching subtest selection tool with DIF items that are modelled unidimensionally. If an item was modelled with uniform DIF or if it had a referent difficulty parameter in the Medium range, it was found to be selected slightly more often for the AT List than the PT List. These trends were seen to increase as sample size increased. All three DIF analyses, and the combined SIBTEST and Crossing SIBTEST, generally were found to perform less well as DIF contaminated the matching subtest, as well as when DIF was modelled less severely or when the focal group ability was skewed. While the combined SIBTEST and Crossing SIBTEST was found to have the highest power among the DIF analyses, it also was found to have Type I error rates that were sometimes extremely high. / Dissertation/Thesis / Doctoral Dissertation Educational Psychology 2014

Differential item functioning (DIF) is present when examinees who have the same level of a trait have a different probability of correctly answering a test item intended to measure that trait (Shepard & Averill, 1981). The following study is a DIF analysis of the Herrmann Brain Dominance Instrument (HBDI), a preference profiling instrument developed by Herrmann International to help individuals identify their dominant preferences and then classify their level of dominance into four preference quadrants. Examinees who completed the American English version of the instrument were classified as the reference group and examinees of the International English version were classified as the focal group. Out of 105 items, 11 were manifesting a large amount of DIF and were flagged for further review. The POLYSIBTEST procedure was used to carry out the DIF analysis. POLYSIBTEST is an extension of the SIBTEST procedure, which is a conceptually simple method for analyzing DIF that uses a latent trait measure rather than an observed total score. The latent trait measure helps detect both uniform and nonuniform DIF and the POLYSIBTEST procedure is used for both dichotomous and polytomous items. Each of the four preference quadrants were analyzed separately to reduce incorrect findings as a result of ipsative scoring. The process used to complete the DIF analysis was documented so that additional language groups may be analyzed by Herrmann International.

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This study formed part of a larger project that is concerned with the adaptation of a test of cognitive academic language proficiency, the Woodcock Muñoz Language Survey (WMLS). The WMLS has been adapted from English into isiXhosa and the present study is located within the broader study that is concerned with establishing overall equivalence between the two language versions of the WMLS. It was primarily concerned with the Verbal Analogies (VA) scale. Previous research on this scale has demonstrated promising results, but continues to find evidence of some inequivalence. This study aimed to cross-validate previous research on the two language versions of the WMLS and improve on methodological issues by employing matched groups. It drew upon an existing dataset from the larger research project. The study employed a monolingual matched two-group design consisting of 150 mainly English speaking and 149 mainly isiXhosa learners in grades 6 and 7. This study had two sub aims. The first was to investigate item bias by identifying DIF items in the VA scale across the isiXhosa and English by conducting a logistic regression and Mantel-Haenszel procedure. Five items were identified by both techniques as DIF. The second sub aim was to evaluate construct equivalence between the isiXhosa and English versions of the WMLS on the VA scale by conducting a factor analysis on the tests after removal of DIF items. Two factors were requested during the factor analysis. The first factor displayed significant loadings across both language versions and was identified as a stable factor. This was confirmed by the Tucker’s Phi and scatter plot. The second factor was stable for the English version but not for the isiXhosa version. The Tucker’s phi and scatter plot indicated that this factor is not structurally equivalent across the two language versions / Magister Artium (Psychology) - MA(Psych)

Cross-cultural studies, like TIMSS and PISA 2003, are being conducted since 1960s with an idea that these assessments can provide a broad perspective for evaluating and improving education. In addition countries can assess their relative positions in mathematics achievement among their competitors in the global world. However, because of the different cultural and language settings of different countries, these international tests may not be functioning as expected across all the countries. Thus, tests may not be equivalent, or fair, linguistically and culturally across the participating countries. In this conte! ! xt, the present study aimed at assessing the equivalence of mathematics items of TIMSS 1999 and PISA 2003 across cultures and languages, to fin! d out if mathematics achievement possesses any culture specifi! c aspect s. For this purpose, the present study assessed Turkish and English versions of TIMSS 1999 and PISA 2003 mathematics items with respect to, (a) psychometric characteristics of items, and (b) possible sources of Differential Item Functioning (DIF) between these two versions. The study used Restricted Factor Analysis, Mantel-Haenzsel Statistics and Item Response Theory Likelihood Ratio methodologies to determine DIF items. The results revealed that there were adaptation problems in both TIMSS and PISA studies. However it was still possible to determine a subtest of items functioning fairly between cultures, to form a basis for a cross-cultural comparison. In PISA, there was a high rate of agreement among the DIF methodologies used. However, in TIMSS, the agree! ment ra! te decreased considerably possibly because the rate o! f differ e! ntially functioning items within TIMSS was higher, and differential guessing and differential discriminating were also issues in the test. The study! also revealed that items requiring competencies of reproduction of practiced knowledge, knowledge of facts, performance of routine procedures, application of technical skills were less likely to be biased against Turkish students with respect to American students at the same ability level. On the other hand, items requiring students to communicate mathematically, items where various results must be compared, and items that had real-world context were less likely to be in favor of Turkish students.