Children’s solutions of logical versus empirical problems: What’s missing and what develops?

This research examined the development of the ability to differentiate logical from empirical problems and the different ways in which children solve these problems. Thirty-two 4- and 5-year-olds, thirty-four 8- and 9-year-olds, and thirty-five 11- and 12-year-olds were given five questions regarding an imaginary character’s predictions as to where a ball would land after being dropped through a ‘tautology machine’. The questions examined encoding and recall of problems, children’s understanding of when evidence was necessary, and children’s evaluation of form and evidence. Data were analyzed in two ways: (1) by comparing differences across participants on component questions and (2) an individual analysis examining the consistency of responses to component questions across the problem set. Overall, the results indicated that: (1) sixth graders tended to differentiate logical from empirical problems while preschool and third grade children rarely did; (2) young children tend to ignore both the logical connective and the second half of problems-termed a ‘cut;’ (3) these cuts are less frequent when a problem is compatible with one empirical possibility; (4) cuts do not stem from encoding or recall errors, but seem to be the product of incomplete problem processing and (5) from third to sixth grade, children’s understanding of logical form increased as the rate of cuts decreased.     

Network Connectivity Dynamics,Cognitive Biases,and the Evolution of Cultural Diversity in Round-Robin Interactive Micro-Societies

The distribution of cultural variants in a population is shaped by both neutral evolutionary dynamics and by selection pressures. The temporal dynamics of social network connectivity, that is, the order in which individuals in a population interact with each other, has been largely unexplored. In this paper, we investigate how, in a fully connected social network, connectivity dynamics, alone and in interaction with different cognitive biases, affect the evolution of cultural variants. Using agent-based computer simulations, we manipulate population connectivity dynamics (early, mid, and late full-population connectivity); content bias, or a preference for high-quality variants; coordination bias, or whether agents tend to use self-produced variants (egocentric bias), or to switch to variants observed in others (allocentric bias); and memory size, or the number of items that agents can store in their memory. We show that connectivity dynamics affect the time-course of variant spread, with lower connectivity slowing down convergence of the population onto a single cultural variant. We also show that, compared to a neutral evolutionary model, content bias accelerates convergence and amplifies the effects of connectivity dynamics, while larger memory size and coordination bias, especially egocentric bias, slow down convergence. Furthermore, connectivity dynamics affect the frequency of high-quality variants (adaptiveness), with late connectivity populations showing bursts of rapid change in adaptiveness followed by periods of relatively slower change, and early connectivity populations following a single-peak evolutionary dynamic. We evaluate our simulations against existing data collected from previous experiments and show how our model reproduces the empirical patterns of convergence.     

Detecting Potential Underreporting of Suicide Ideation Among U.S. Military Personnel

Using a military sample comprised largely of National Guard personnel, zero‐inflation negative binomial regression was applied to estimate the effects of indirect, nonface valid indicators of suicide ideation [Thwarted Belongingness (TB), Perceived Burdensomeness (PB), and Hopelessness], in predicting suicide ideation. Data from a sample of 497 military personnel (82.1% male; m_age = 27.24; range = 18–59) were analyzed. TB and the interaction of TB with Hopelessness were significant predictors in the logistic regression, and in the negative binomial regression, the main effects of TB and hopelessness, and the interactions of TB with hopelessness and PB with hopelessness were significant. The findings further indicated that approximately 10% of those not reporting ideation would be predicted to be ideators. Clinically, these results indicate that, in samples reluctant to report ideation, the assessment of suicide risk may improve through the use of relevant measures that do not explicitly reference suicide thoughts.