title: On the relevance of assumptions associated with classical factor analytic approaches.
abstract: A personal trait, for example a person's cognitive ability, represents a theoretical concept postulated to explain behavior. Interesting constructs are latent, that is, they cannot be observed. Latent variable modeling constitutes a methodology to deal with hypothetical constructs. Constructs are modeled as random variables and become components of a statistical model. As random variables, they possess a probability distribution in the population of reference. In applications, this distribution is typically assumed to be the normal distribution. The normality assumption may be reasonable in many cases, but there are situations where it cannot be justified. For example, this is true for criterion-referenced tests or for background characteristics of students in large scale assessment studies. Nevertheless, the normal procedures in combination with the classical factor analytic methods are frequently pursued, despite the effects of violating this "implicit" assumption are not clear in general. In a simulation study, we investigate whether classical factor analytic approaches can be instrumental in estimating the factorial structure and properties of the population distribution of a latent personal trait from educational test data, when violations of classical assumptions as the aforementioned are present. The results indicate that having a latent non-normal distribution clearly affects the estimation of the distribution of the factor scores and properties thereof. Thus, when the population distribution of a personal trait is assumed to be non-symmetric, we recommend avoiding those factor analytic approaches for estimation of a person's factor score, even though the number of extracted factors and the estimated loading matrix may not be strongly affected. An application to the Progress in International Reading Literacy Study (PIRLS) is given. Comments on possible implications for the Programme for International Student Assessment (PISA) complete the presentation.
authors.affiliation: Chair for Methods in Empirical Educational Research, TUM School of Education and Centre for International Student Assessment, Technische Universität München Munich, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kasper
authors.forename: Ali
authors.initials: A
authors.lastname: Unlü
keywords: Programme for International Student Assessment; Progress in International Reading Literacy Study; criterion-referenced test; factor analysis; factorial structure; large scale educational assessment; latent variable model; normality assumption
references.citation: Multivariate Behav Res. 1986 Jul 1;21(3):377-91
references.pmid: 26800967
references.citation: Multivariate Behav Res. 1996 Oct 1;31(4):517-38
references.pmid: 26788596
references.citation: Multivariate Behav Res. 1997 Oct 1;32(4):355-73
references.pmid: 26777072
references.citation: Psychometrika. 1965 Jun;30:179-85
references.pmid: 14306381
references.citation: J Pers Assess. 1997 Jun;68(3):532-60
references.pmid: 16372866
references.citation: Psychol Bull. 1955 Jul;52(4):281-302
references.pmid: 13245896
references.citation: Multivariate Behav Res. 1990 Jan 1;25(1):1-28
references.pmid: 26741964
references.citation: Front Psychol. 2012 Mar 01;3:55
references.pmid: 22403561
references.citation: Multivariate Behav Res. 1966 Apr 1;1(2):245-76
references.pmid: 26828106
references.citation: Psychol Methods. 2007 Mar;12(1):58-79
references.pmid: 17402812
references.citation: Psychometrika. 1966 Jun;31(2):165-78
references.pmid: 5222205