2 Taxonomy is always a contentious issue because the world does not come to us in neat little packages (S. Personality has been conceptualized from a variety of theoretical perspectives, and at various levels of Each of these levels has made unique contributions to our understanding of individual differences in behavior and experience. However, the number of personality traits, and scales designed to measure them, escalated without an end in sight (Goldberg, 1971). Researchers, as well as practitioners in the field of personality assessment, were faced with a bewildering array of personality scales from which to choose, with little guidance and no overall rationale at hand. What made matters worse was that scales with the same name often measure concepts that are not the same, and scales with different names often measure concepts that are quite similar. Although diversity and scientific pluralism are useful, the systematic accumulation of findings and the communication among researchers became difficult amidst the Babel of concepts and scales. Many personality researchers had hoped that they might devise the structure that would transform the Babel into a community speaking a common language. However, such an integration was not to be achieved by any one researcher or by any one theoretical perspective. As Allport once put it, " each assessor has his own pet units and uses a pet battery of diagnostic devices " (1958, p. 258). What personality psychology needed was a descriptive model, or taxonomy, of its subject matter. One of the central goals of scientific taxonomies is the definition of overarching domains within which large numbers of specific instances can be understood in a simplified way. Thus, in personality psychology, a taxonomy would permit researchers to study specified domains of personality characteristics, rather than examining separately the thousands of particular attributes that make human beings individual and unique. Moreover, a generally accepted taxonomy would greatly facilitate the accumulation and communication of empirical findings by offering a standard vocabulary, or nomenclature. After decades of research, the field is approaching consensus on a general taxonomy of personality traits, the " Big Five " personality dimensions. These dimensions do not represent a particular theoretical perspective but were derived from analyses of the natural-language terms people use to describe themselves 3 and others. Rather than replacing all previous systems, the Big Five taxonomy serves an integrative function because it can represent the various and diverse systems of personality …

The Big Five Trait taxonomy: History, measurement, and theoretical perspectives.

This personal historical article traces the development of the Big-Five factor structure, whose growing acceptance by personality researchers has profoundly influenced the scientific study of individual differences. The roots of this taxonomy lie in the lexical hypothesis and the insights of Sir Francis Galton, the prescience of L. L. Thurstone, the legacy of Raymond B. Cattell, and the seminal analyses of Tupes and Christal. Paradoxically, the present popularity of this model owes much to its many critics, each of whom tried to replace it, but failed. In reaction, there have been a number of attempts to assimilate other models into the five-factor structure. Lately, some practical implications of the emerging consensus can be seen in such contexts as personnel selection and classification.

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The Structure of Phenotypic Personality Traits

Pedagosko i psiholosko testiranje i procjenjivanje spadaju među najvažnije doprinose znanosti o ponasanju nasem drustvu i pružaju temeljna i znacajna poboljsanja u odnosu na ranije postupke. Iako se ne može ustvrditi da su svi testovi dovoljno usavrseni niti da su sva testiranja razborita i korisna, postoji velika kolicina informacija koje ukazuju na ucinkovitost kvalitetnih instrumenata u onim situacijama u kojima je njihovo koristenje potkrijepljeno validacijskim podacima. Pravilna upotreba testova može dovesti do boljih odluka o pojedincima i programima nego sto bi to bio slucaj bez njihovog koristenja, a također i ukazati na put za siri i pravedniji pristup obrazovanju i zaposljavanju. Međutim, losa upotreba testova može dovesti do zamjetne stete nanesene ispitanicima i drugim sudionicima u procesu donosenja odluka na temelju testovnih podataka. Cilj Standarda je promoviranje kvalitetne i eticne upotrebe testova te uspostavljanje osnovice za ocjenu kvalitete postupaka testiranja. Svrha objavljivanja Standarda je uspostavljanje kriterija za evaluaciju testova, provedbe testiranja i posljedica upotrebe testova. Iako bi evaluacija prikladnosti testa ili njegove primjene trebala ovisiti prvenstveno o strucnim misljenjima, Standardi pružaju okvir koji osigurava obuhvacanje svih relevantnih pitanja. Bilo bi poželjno da svi autori, sponzori, nakladnici i korisnici profesionalnih testova usvoje Standarde te da poticu druge da ih također prihvate.

Standards for educational and psychological testing

On robust estimation of the location parameter

Measurement and control of response bias.

In this study, we investigated to what extent exemplar-based and prototype predictors can be applied to predicting categorization in natural language concepts. Participants categorized novel tropical foods into two well-known natural language concepts: fruits and vegetables. The results indicate that both the prototype predictors and the exemplar predictors contribute significantly in accounting for the categorization choices but that the contribution of the prototype predictor comes from just a limited number of features.

/pdf/categorization-of-novel-stimuli-in-well-known-natural-h238umxf3r.pdf

Categorization of novel stimuli in well-known natural concepts: a case study.

Two generalizations of the Rasch model are compared: the between-item multidimensional model (Adams, Wilson, and Wang, 1997), and the mixture Rasch model (Mislevy & Verhelst, 1990; Rost, 1990). It is shown that the between-item multidimensional model is formally equivalent with a continuous mixture of Rasch models for which, within each class of the mixture, the item parameters are equal to the item parameters of the multidimensional model up to a shift parameter that is specific for the dimension an item belongs to in the multidimensional model. In a simulation study, the relation between both types of models also holds when the number of classes of the mixture is as small as two. The relation is illustrated with a study on verbal aggression.

A relation between a between-item multidimensional IRT model and the mixture rasch model

An IRT model with a parameter-driven process for change is proposed. Quantitative differences between persons are taken into account by a continuous latent variable, as in common IRT models. In addition, qualitative interindividual differences and autodependencies are accounted for by assuming within-subject variability with respect to the parameters of the IRT model. In particular, the parameters of the IRT model are governed by an unobserved or “hidden'” homogeneous Markov process. The model includes the mixture linear logistic test model (Mislevy & Verhelst, 1990), the mixture Rasch model (Rost, 1990), and the Saltus model (Wilson, 1989) as specific instances. The model is applied to a longitudinal experiment on discontinuity in conservation acquisition (van der Maas, 1993).

https://hvandermaas.socsci.uva.nl/Homepage_Han_van_der_Maas/Publications_files/papers/rijmen.pdf

An irt model with a parameter-driven process for change

Multiple item response profile (MIRP) models are models with crossed fixed and random effects. At least one between-person factor is crossed with at least one within-person factor, and the persons nested within the levels of the between-person factor are crossed with the items within levels of the within-person factor. Maximum likelihood estimation (MLE) of models for binary data with crossed random effects is challenging. This is because the marginal likelihood does not have a closed form, so that MLE requires numerical or Monte Carlo integration. In addition, the multidimensional structure of MIRPs makes the estimation complex. In this paper, three different estimation methods to meet these challenges are described: the Laplace approximation to the integrand; hierarchical Bayesian analysis, a simulation-based method; and an alternating imputation posterior with adaptive quadrature as the approximation to the integral. In addition, this paper discusses the advantages and disadvantages of these three estimation methods for MIRPs. The three algorithms are compared in a real data application and a simulation study was also done to compare their behaviour.

Paul De Boeck

Papers

Categorization of novel stimuli in well-known natural concepts: a case study.

A relation between a between-item multidimensional IRT model and the mixture rasch model

An irt model with a parameter-driven process for change

Parameter estimation of multiple item response profile model.

Verbal fluency and verbal comprehension abilities in synonym tasks