INFORMATION

Psicothema was founded in Asturias (northern Spain) in 1989, and is published jointly by the Psychology Faculty of the University of Oviedo and the Psychological Association of the Principality of Asturias (Colegio Oficial de Psicólogos del Principado de Asturias).
We currently publish four issues per year, which accounts for some 100 articles annually. We admit work from both the basic and applied research fields, and from all areas of Psychology, all manuscripts being anonymously reviewed prior to publication.

PSICOTHEMA
  • Director: Laura E. Gómez Sánchez
  • Frequency:
         February | May | August | November
  • ISSN: 0214-9915
  • Digital Edition:: 1886-144X
CONTACT US
  • Address: Ildelfonso Sánchez del Río, 4, 1º B
    33001 Oviedo (Spain)
  • Phone: 985 285 778
  • Fax: 985 281 374
  • Email:psicothema@cop.es

Reliability and External Validity of Personality Test Scores: The Role of Person and Item Error

Pere J. Ferrando, and David Navarro-González

Universitat Rovira i Virgili

Background: This article explores the suitability of a proposed “Dual” model, in which both people and items are sources of measurement error, by assessing how the test scores are expected to behave in terms of marginal reliability and external validity when the model holds. Method: Analytical derivations are produced for predicting: (a) the impact of person and item errors in the amount of marginal reliability and external validity, as well as the occurrence of “ceiling” effects; (b) the changes in test reliability across groups with different average amounts of person error, and (c) the phenomenon of differential predictability. Two empirical studies are also used both as an illustration and as a check of the predicted results. Results: Results show that the model-based predictions agree with existing evidence as well as with basic principles in classical test theory. However, the additional inclusion of individuals as a source of error leads to new explanations and predictions. Conclusions: The proposal and results provide new sources of information in personality assessment as well as of evidence of model suitability. They also help to explain some disappointing recurrent results.

Fiabilidad y Validez Externa de las Puntuaciones en los Tests de Personalidad: El Papel del Error en las Personas y en los Ítems. Antecedentes: se explora la adecuación de un modelo “Dual” en el que ítems y personas son fuente de error de medida, evaluando como se espera que se comporten las puntuaciones en un test en términos de fiabilidad y validez cuando el modelo se cumple. Método: se derivan analíticamente predicciones respecto a: (a) el impacto del error en personas y en ítems en las estimaciones de fiabilidad y validez externa, así como en efectos techo esperados, (b) cambios en la fiabilidad marginal en grupos con diferente magnitud media de error individual, y (c) el fenómeno de la predictibilidad diferencial. Se incluyen dos estudios empíricos a efectos de ilustración y verificación empírica. Resultados: las predicciones concuerdan con la evidencia acumulada y con los principios de la teoría clásica del test. Sin embargo, la inclusión del parámetro de error individual permite llegar a nuevas explicaciones y predicciones. Conclusiones: la propuesta y resultados proporcionan nuevas fuentes de información en la medida de la personalidad, así como evidencia de la adecuación del modelo. También explican algunos resultados decepcionantes y recurrentes.

PDF

Impact factor 2022:  JCR WOS 2022:  FI = 3.6 (Q2);  JCI = 1.21 (Q1) / SCOPUS 2022:  SJR = 1.097;  CiteScore = 6.4 (Q1)