A new genus and species for the amiiform fishes previously assigned to Amiopsis from the Early Cretaceous of Las Hoyas, Cuenca, Spain

The Mesozoic actinopterygian fish Amiopsis has been reported from three different localities in the Iberian Peninsula. Amiopsis woodwardi was described from the Berriasian–Valanginian of El Montsec (Lérida, Spain). Isolated vertebral centra referred to Amiopsis were found in the Barremian of Buenache de la Sierra (Cuenca, Spain). Finally, amiiform material from the Barremian of Las Hoyas (Cuenca, Spain) were reported as Amiopsis cf. A. woodwardi, due to the overall similarity with the species from El Montsec. Here a detailed anatomical description of the material from Las Hoyas is provided for the first time. The unique combination of characters seen in this taxon, some of which are not shared with Amiopsis but with more derived amiids, indicates that it represents a new taxon, which is here named Hispanamia newbreyi gen. nov., sp. nov

History of two lineages: Comparative analysis of the fossil record in Amiiformes and Pycnodontiformes (Osteischtyes, Actinopterygii)

Amiiformes and pycnodontiformes are two orders of neopterygian fishes that were broadly distributed, and frequently appeared together, during the Mesozoic. Comparison of their fossil record reveals both common traits and significant differences. They both appeared in the Western Tethys and reached maximum diversity during the Cretaceous. The differences in their evolutionary history involve dissimilar patterns of diversity and disparity; pycnodonts are more diversified taxonomically and present larger ecomorphological disparity. This implies that they used different strategies to compete with teleosts, which were unable to displace them from their specialized niches for more than 100 ka. The reasons why this did not happen sooner are difficult to approach, and may include radical environmental changes (i.e., marine transgressions, opening of the Atlantic, closing of the Tethys and opening of the Mediterranean). It is nonetheless clear that the evolutionary novelties of the Teleostei per se were not enough to grant them advantage in the competition for the ichthyofagous and durophagous niches at least during the Late Triassic, the whole Jurassic and the Early Cretaceou

Are fit indices really fit to estimate the number of factors with categorical variables?: some cautionary findings via Monte Carlo Simulation

This paper is not the copy of record and may not exactly replicate the authoritative document published in the APA journal. Please do not copy or cite without author's permission. The final article is available, upon publication, at: http://dx.doi.org/10.1037/met0000064An early step in the process of construct validation consists of establishing the fit of an unrestricted "exploratory" factorial model for a prespecified number of common factors. For this initial unrestricted model, researchers have often recommended and used fit indices to estimate the number of factors to retain. Despite the logical appeal of this approach, little is known about the actual accuracy of fit indices in the estimation of data dimensionality. The present study aimed to reduce this gap by systematically evaluating the performance of 4 commonly used fit indices-the comparative fit index (CFI), the Tucker-Lewis index (TLI), the root mean square error of approximation (RMSEA), and the standardized root mean square residual (SRMR)-in the estimation of the number of factors with categorical variables, and comparing it with what is arguably the current golden rule, Horn's (1965) parallel analysis. The results indicate that the CFI and TLI provide nearly identical estimations and are the most accurate fit indices, followed at a step below by the RMSEA, and then by the SRMR, which gives notably poor dimensionality estimates. Difficulties in establishing optimal cutoff values for the fit indices and the general superiority of parallel analysis, however, suggest that applied researchers are better served by complementing their theoretical considerations regarding dimensionality with the estimates provided by the latter metho

Calibración con parámetros de los ítems fijos para la evaluación del funcionamiento diferencial del ítem en tests adaptativos informatizados

In computerized adaptive testing pretest items are presented in conjunction with operational items to renew the item bank. Pretest items are calibrated, and possible differential item functioning (DIF) is analyzed. Some difficulties arise due to the large amount of missing responses, which can be avoided by the use of fixed item parameter calibration (FIPC; Kim, 2006) methods. In this study, we applied the multiple weights updating and multiple EM cycles method, with response imputation (as suggested by Lei, Chen, & Yu, 2006) and without response imputation for non-applied items. The IRT likelihood ratio test (IRT-LRT) was used for DIF detection. The manipulated factors were type of DIF, DIF size, impact size, test length, and sample size. The results showed that the FIPC method is suitable for detecting large-size DIF in large samples. In the presence of impact the use of imputation led to a bias in the effect-size measure of the DIFEn tests adaptativos informatizados los ítems pretest se presentan junto con los ítems operativos para renovar el banco de ítems. Los ítems pretest se calibran y se analiza el posible funcionamiento diferencial de los ítems (FDI). Este análisis presenta algunos problemas debido a la gran cantidad de respuestas faltantes, una de las posibles soluciones es el uso de métodos de calibración con parámetros fijos (Kim, 2006). En este estudio, aplicamos el método de múltiples actualizaciones de los pesos y múltiples ciclos EM con imputación de respuestas (tal y como propusieron Lei, Chen, y Yu, 2006) y sin imputación de respuesta para los ítems no aplicados. Empleamos el test de razón de verosimilitudes de la TRI para la detección del FDI. Los factores manipulados fueron el tipo de FDI, el tamaño del FDI, el tamaño del impacto, la longitud del test, y el tamaño de las muestras. Los resultados señalan que el método de calibración con parámetros fijos es una alternativa adecuada para la detección de un FDI grande cuando se utilizaron muestras grandes. En presencia de impacto el uso de imputación de respuestas introdujo un sesgo en las medidas del tamaño del efecto del FDIThis research was partly supported by a grant from the Spanish Ministry of Education and Science [PSI2009-10341

Modeling general, specific, and method variance in personality measures: Results for ZKA-PQ and NEO-PI-R

Reprinted by permission of SAGE PublicationsContemporary models of personality assume a hierarchical structure in which broader traits contain narrower traits. Individual differences in response styles also constitute a source of score variance. In this study, the bifactor model is applied to separate these sources of variance for personality subscores. The procedure is illustrated using data for two personality inventories—NEO Personality Inventory–Revised and Zuckerman–Kuhlman–Aluja Personality Questionnaire. The inclusion of the acquiescence method factor generally improved the fit to acceptable levels for the Zuckerman–Kuhlman–Aluja Personality Questionnaire, but not for the NEO Personality Inventory–Revised. This effect was higher in subscales where the number of direct and reverse items is not balanced. Loadings on the specific factors were usually smaller than the loadings on the general factor. In some cases, part of the variance was due to domains being different from the main one. This information is of particular interest to researchers as they can identify which subscale scores have more potential to increase predictive validit

The use of IRT to investigate the relationships between the g factor and cognitive tasks

Las relaciones entre el factor g y tareas de procesamiento de la información han abierto la puerta a la comprensión de la naturaleza de g ( Jensen, 1998). No obstante, es necesario superar determinados problemas metodológicos para poder comprender hasta qué punto las diferencias en g son ocasionadas por diferencias en procesos cognitivos. En este sentido, la falta de fiabilidad de las puntuaciones en las tareas de procesos puede llevar a conclusiones equivocadas sobre la naturaleza de dichas relaciones. Un medio de abordar este problema es seleccionar a las personas con un menor error de estimación del nivel de habilidad. Los resultados muestran un aumento de las correlaciones entre g y memoria de trabajo en el grupo de sujetos mejor medidos frente al grupo de personas con un error de estimación mayorMany authors have looked for the relations between the g factor and cognitive tasks in order to find out the nurture of the g factor (Jensen, 1998). Nevertheless, some methodological problems must be solved to understand if the individual differences in g are differences in cognitive processes. One of them is the low reliability of the scores in this kind of tasks. On the grounds of the standard error of the ability level estimation, we hypothesized that the correlations between the g factor and a working memory task would be larger in the g roup of the subjects better measured (less standard error). The results support this hypothesi

Rotating item banks versus restriction of maximum exposure rates in computerized adaptive testing

If examinees were to know, beforehand, part of the content of a computerized adaptive test, their estimated trait levels would then have a marked positive bias. One of the strategies to avoid this consists of dividing a large item bank into several sub-banks and rotating the sub-bank employed (Ariel, Veldkamp & van der Linden, 2004). This strategy permits substantial improvements in exposure control at little cost to measurement accuracy. However, we do not know whether this option provides better results than using the master bank with greater restriction in the maximum exposure rates (Sympson & Hetter, 1985). In order to investigate this issue, we worked with several simulated banks of 2100 items, comparing them, for RMSE and overlap rate, with the same banks divided in two, three… up to seven sub-banks. By means of extensive manipulation of the maximum exposure rate in each bank, we found that the option of rotating banks slightly outperformed the option of restricting maximum exposure rate of the master bank by means of the Sympson-Hetter method.Si los examinandos conocieran de antemano una parte del contenido de un test adaptativo informatizado, sus niveles estimados de rasgo tendrían un marcado sesgo positivo. Una de las estrategias para evitar esto consiste en dividir un gran banco de ítems en varios sub-bancos y rotar el sub-banco empleado (Ariel, Veldkamp & van der Linden, 2004). Esta estrategia permite mejoras sustanciales en el control de la exposición con poca merma de la precisión de la medida. Sin embargo, no sabemos si esta opción proporciona mejores resultados que el uso del banco maestro con más restricción en la tasa máxima de exposición (Sympson & Hetter, 1985). Para investigar este problema, trabajamos con varios bancos simulados de 2100 ítems, comparándolos, en RMSE y en tasa de solapamiento, con los mismos bancos divididos en dos, tres… hasta siete sub-bancos. Mediante manipulación extensa de la tasa máxima de exposición en cada banco, encontramos que la opción de rotar los bancos ofrecía resultados ligeramente mejores que la opción de restringir la tasa máxima de exposición del banco maestro mediante el método Sympson-Hetter

Métodos de detección del falseamiento en test online

Background: Unproctored Internet Tests (UIT) are vulnerable to cheating attempts by candidates to obtain higher scores. To prevent this, subsequent procedures such as a verification test (VT) is carried out. This study compares five statistics used to detect cheating in Computerized Adaptive Tests (CATs): Guo and Drasgow’s Z-test, the Adaptive Measure of Change (AMC), Likelihood Ratio Test (LRT), Score Test, and Modified Signed Likelihood Ratio Test (MSLRT). Method: We simulated data from honest and cheating candidates to the UIT and the VT. Honest candidates responded to the UIT and the VT with their real ability level, while cheating candidates responded only to the VT, and different levels of cheating were simulated. We applied hypothesis tests, and obtained type I error and power rates. Results: Although we found differences in type I error rates between some of the procedures, all procedures reported quite accurate results with the exception of the Score Test. The power rates obtained point to MSLRT’s superiority in detecting cheating. Conclusions: We consider the MSLRT to be the best test, as it has the highest power rate and a suitable type I error rate.Antecedentes: las pruebas de selección en línea sin vigilancia (UIT) son vulnerables a intentos de falseamiento para obtener puntuaciones superiores. Por ello, en ocasiones se utilizan procedimientos de detección, como aplicar posteriormente un test de verifi cación (VT). El objetivo del estudio es comparar cinco contrastes estadísticos para la detección del falseamiento en Test Adaptativos Informatizados: Z-test de Guo y Drasgow, Medida de Cambio Adaptativa (AMC), Test de Razón de Verosimilitudes (LRT), Score Test y Modifi ed Signed Likelihood Ratio Test (MSLRT). Método: se simularon respuestas de participantes honestos y falseadores al UIT y al VT. Para los participantes honestos se simulaban en ambos en función de su nivel de rasgo real; para los falseadores, solo en el VT, y en el UIT se simulaban distintos grados de falseamiento. Después, se obtenían las tasas de error tipo I y potencia. Resultados: Se encontraron diferencias en las tasas de error tipo I entre algunos procedimientos, pero todos menos el Score Test se ajustaron al valor nominal. La potencia obtenida era signifi cativamente superior con el MSLRT. Conclusiones: consideramos que MSLRT es la mejor alternativa, ya que tiene mejor potencia y una tasa de error tipo I ajustada.This research was partially supported by Ministerio de Ciencia, Innovación y Universidades, Spain (Grant PSI2017-85022-P), European Social Fund, and Cátedra de Modelos y Aplicaciones Psicométricos (Instituto de Ingeniería del Conocimiento and Autonomous University of Madrid)