Tuesday, April 06, 2021

The Relationship between Theory of Mind and Intelligence: A Formative g Approach

The Relationship between Theory of Mind and Intelligence: A Formative g Approach

Theory of Mind (ToM) is the ability understand that other people's mental states may be different from one's own. Psychometric models have shown that individual differences in ToM can largely be attributed to general intelligence (g) (Coyle et al. 2018). Most psychometric models specify g as a reflective latent variable, which is interpreted as a general ability that plays a causal role in a broad range of cognitive tasks, including ToM tasks. However, an alternative approach is to specify g as a formative latent variable, that is, an overall index of cognitive ability that does not represent a psychological attribute (Kovacs and Conway 2016). Here we consider a formative g approach to the relationship between ToM and intelligence. First, we conducted an SEM with reflective g to test the hypothesis that ToM is largely accounted for by a general ability. Next, we conducted a model with formative g to determine whether the relationship between ToM and intelligence is influenced by domain-specific tasks. Finally, we conducted a redundancy analysis to examine the contribution of each g variable. Results suggest that the relationship between ToM and intelligence in this study was influenced by language-based tasks, rather than solely a general ability.

Kevin S. McGrew, PhD
Educational & School Psychologist
Institute for Applied Psychometrics (IAP)

Nice followup and extension of Floyd et al (2018) IQ exchangeability study

Limited Internal Comparability of General Intelligence Composites: Impact on External Validity, Possible Predictors, and Practical Remedies


Silvia Grieder1 , Anette Bünger1 , Salome D. Odermatt1 , Florine Schweizer1, and Alexander Grob1


Research on comparability of general intelligence composites (GICs) is scarce and has focused exclusively on comparing GICs from different test batteries, revealing limited individual-level comparability. We add to these findings, investigating the group- and individual-level comparability of different GICs within test batteries (i.e., internal score comparability), thereby minimizing transient error and ruling out between-battery variance completely. We (a) determined the magnitude of intraindividual IQ differences, (b) investigated their impact on external validity, (c) explored possible predictors for these differences, and (d) examined ways to deal with incomparability. Results are based on the standardization samples of three intelligence test batteries, spanning from early childhood to late adulthood. Despite high group-level comparability, individual-level comparability was often unsatisfactory, especially toward the tails of the IQ distribution. This limited comparability has consequences for external validity, as GICs were differentially related to and often less predictive for school grades for individuals with high IQ differences. Of several predictors, only IQ level and age were systematically related to comparability. Consequently, findings challenge the use of overall internal consistencies for confidence intervals and suggest using confidence intervals based on test–retest reliabilities or age- and IQ-specific internal consistencies for clinical interpretation. Implications for test construction and application are discussed.

Keywords.  general intelligence, IQ, screening, individual level, reliability, validity

Friday, April 02, 2021

Theories and measurement of intelligence. - PsycNET


Floyd, R. G., Farmer, R. L., Schneider, W. J., & McGrew, K. S. (2021). Theories and measurement of intelligence. In L. M. Glidden, L. Abbeduto, L. L. McIntyre, & M. J. Tassé (Eds.), APA handbooks in psychology®. APA handbook of intellectual and developmental disabilities: Foundations (p. 385–424). American Psychological Association. https://doi.org/10.1037/0000194-015

Advancements in the measurement of intellectual functioning via individually administered intelligence tests during the early 1900s led to reliance on IQs to represent the deficits in intellectual functioning during the past century. Concurrent development of models of intelligence also advanced understanding and measurement of intellectual functioning, and the current consensus is that intellectual functioning is best represented by a latent ability referred to as general intelligence (or psychometric g), as well as numerous broad and narrow abilities. As a result of these developments, the practice of identification of persons with intellectual disability (ID) is now based on a stronger scientific foundation. This chapter discusses three models of intelligence and reviews the genetic and environmental influences on intellectual functioning across the population, and persons with ID in particular. It culminates with a description of best practices and emerging methods in the assessment of intellectual functioning. (PsycInfo Database Record (c) 2020 APA, all rights reserved)

Kevin S. McGrew,  PhD
Educational Psychologist
Institute for Applied Psychometrics (IAP)