A Simple Test of the Concurrent Validity of the Social Interest Index

To assess the concurrent validity of the Social Interest Index (SII), we examined the relationships between subjects' social interest scores and their number and frequency of social contacts. As hypothesized, subjects' SII scores were related in a positive, significant manner to their reported number of close friends, number of relatives they felt close to, and number of monthly friend/relative contacts (all ps < .01). The results, which showed a positive relationship between social interest and social contacts, support the concurrent validity of the SII.     

Executive functioning moderates the relationship between motivation and adolescent depressive symptoms

We investigated the association between adolescent depressive symptoms and components of executive functioning (EF), including planning (Tower of London), set-shifting (Wisconsin Card Sorting Task), and inhibition (Stop Signal Task) in a community sample of 12–14 year olds. Further, EF was tested as a moderator of motivation (as operationalized by revised Reinforcement Sensitivity Theory) effects on depressive symptoms. Results suggested that planning ability was associated with depressive symptoms. Furthermore, planning ability moderated the relationship between motivation (fight-flight–freeze system; FFFS) and depressive symptoms, such that among adolescents with poor planning ability the FFFS positively predicted depressive symptoms, but among adolescents with strong planning ability the FFFS negatively predicted depressive symptoms. Neither set-shifting nor inhibition were associated with depressive symptoms. Findings highlight the need to consider multiple components of EF and to integrate motivational and executive dysfunction models to the study of depression.     

Algorithmic complexity for psychology: a user-friendly implementation of the coding theorem method

Kolmogorov-Chaitin complexity has long been believed to be impossible to approximate when it comes to short sequences (e.g. of length 5-50). However, with the newly developed coding theorem method the complexity of strings of length 2-11 can now be numerically estimated. We present the theoretical basis of algorithmic complexity for short strings (ACSS) and describe an R-package providing functions based on ACSS that will cover psychologists’ needs and improve upon previous methods in three ways: (1) ACSS is now available not only for binary strings, but for strings based on up to 9 different symbols, (2) ACSS no longer requires time-consuming computing, and (3) a new approach based on ACSS gives access to an estimation of the complexity of strings of any length. Finally, three illustrative examples show how these tools can be applied to psychology.     

Birkhoff-like sheaf representation for varieties of lattice expansions

Given a variety we study the existence of a class such that S1 every A can be represented as a global subdirect product with factors in and S2 every non-trivial A is globally indecomposable. We show that the following varieties (and its subvarieties) have a class satisfying properties S1 and S2: p-algebras, distributive double p-algebras of a finite range, semisimple varieties of lattice expansions such that the simple members form a universal class (bounded distributive lattices, De Morgan algebras, etc) and arithmetical varieties in which the finitely subdirectly irreducible algebras form a universal class (f-rings, vector groups, Wajsberg algebras, discriminator varieties, Heyting algebras, etc). As an application we obtain results analogous to that of Nachbin saying that if every chain of prime filters of a bounded distributive lattice has at most length 1, then the lattice is Boolean.We wish to thank Lic. Alfredo Guerin and Dr. Daniel Penazzi for helping us with linguistics aspects. We are indebted to the referee for several helpful suggestions. We also wish to thank Professor Mick Adams for providing us with several reprints and useful e-mail information on the subject.Suported by CONICOR and SECyT (UNC).