Less means more for pigeons but not always

When humans are asked to judge the value of a set of objects of excellent quality, they often give this set higher value than those same objects with the addition of some of lesser quality. This is an example of the affect heuristic, often referred to as the less-is-more effect. Monkeys and dogs, too, have shown this suboptimal effect. But in the present experiments, normally hungry pigeons chose optimally: a preferred food plus a less--preferred food over a more-preferred food alone. In Experiment 2, however, pigeons on a less-restricted diet showed the suboptimal less-is-more effect. Choice on control trials indicated that the effect did not result from the novelty of two food items versus one. The effect in the less-food-restricted pigeons appears to result from the devaluation of the combination of the food items by the presence of the less-preferred food item. The reversal of the effect under greater food restriction may occur because, as motivation increases, the value of the less-preferred food increases faster than the value of the more-preferred food, thus decreasing the difference in value between the two foods.     

Gender Differences in the Social Cost of Affective Deviance

The current study tested whether men and women receive different degrees of social punishment for violating norms of emotional expression. Participants watched videos of male and female targets (whose reactions were pre-tested to be equivalent in expressivity and valence) viewing either a positive or negative slideshow, with their emotional reaction to the slideshow manipulated to be affectively congruent, affectively incongruent, or flat. Participants then rated the target on a number of social evaluation measures. Displaying an incongruent emotional expression, relative to a congruent one, harmed judgments of women more than men. Women are expected to be more emotionally expressive than men, making an incongruent expression more deviant for women. These results highlight the importance of social norms in construing another person’s emotion displays, which can subsequently determine acceptance or rejection of that person.     

Rejoinder: Remaining Challenges in Investigating Grade-Retention Effectiveness

This rejoinder, in response to the commentaries of Steiner, Park, and Kim (this issue) and Reshetnyak, Cham, and Hughes (this issue), discusses remaining challenges in grade retention research. First, a same-age comparison assumes that the instruments used in different grades measure ability equally well. We discuss the importance of evaluating the properties of the scaling process to address whether this assumption has been met. Second, we discuss issues in the selection of covariates to be included in the weights. Third, we discuss the unconfoundedness assumption and the problem of remaining imbalance. Finally, we provide an empirical illustration showing that studying grade-retention effectiveness comes with multiple methodological decisions that are rooted in a bias–variance trade-off.     

Motivational interviewing and self-determination theory in a web-based computer tailored physical activity intervention: A randomized controlled trial

Objective: This study explores whether a web-based physical activity (PA) intervention grounded in self-determination theory (SDT) and motivational interviewing (MI) is more effective and better appreciated than a traditional web-based PA intervention.

Design: A randomized controlled trial was conducted, comparing (1) I Move; a web-based PA intervention based on SDT and MI, (2) Active Plus; a traditional web-based PA intervention and (3) a waiting list control condition.

Main outcome measures: Weekly minutes of moderate to vigorous PA and weekly days with ≥30 min PA were measured through self-report at baseline and at 3 and 6 months from baseline.

Results: I Move achieved a small, but significant increase in weekly minutes of moderate to vigorous PA, while Active Plus did not have a significant impact on this outcome. Both interventions were effective in increasing weekly days with ≥30 min PA, whereas Active Plus yielded a greater effect on this outcome.

Conclusion: Overall, the web-based PA intervention grounded in SDT and MI did not outperform the traditional web-based PA intervention. Further research should reveal whether this type of intervention is profitable for long-term maintenance of PA levels.     

Sex Object vs. Athlete: Boys’ and Men’s Responses Toward Sexualized Male Athletes

Using a between-participants experimental paradigm, the present study investigated U.S. adolescent boys’ (n = 96) and college men’s (n = 194) attitudes toward media images of male athletes as well as their thoughts about the athletes. Participants viewed either sexualized (i.e., skin exposed, sexual pose) or performance (i.e., in uniform and in action poses on the field/court) images of male athletes. They then rated the athletes’ competence, esteem, and sexual appeal and completed a writing task about their reactions to the images. Male viewers rated the sexualized athletes lower in competence and esteem and higher in sexual appeal compared to the performance athletes. These results have implications for advocacy efforts calling for less sexualization in today’s media environment. 

     

The temporal structure of goal-directed and habitual operant behavior

Operant behavior can reflect the influence of goal-directed and habitual processes. These can be distinguished by changes to response rate following devaluation of the reinforcing outcome. Whether a response is goal directed or habitual depends on whether devaluation affects response rate. Response rate can be decomposed into frequencies of bouts and pauses by analyzing the distribution of interresponse times. This study sought to characterize goal-directed and habitual behaviors in terms of bout-initiation rate, within-bout response rate, bout length, and bout duration. Data were taken from three published studies that compared sensitivity to devaluation following brief and extended training with variable-interval schedules. Analyses focused on goal-directed and habitual responding, a comparison of a habitual response to a similarly trained response that had been converted back to goal-directed status after a surprising event, and a demonstration of contextual control of habit and goal direction in the same subjects. Across experiments and despite responses being clearly distinguished as goal directed and habitual by total response rate, analyses of bout-initiation rate, within-bout rate, bout length, and bout duration did not reveal a pattern that distinguished goal-directed from habitual responding.     

School barricaded captive-taking: A literature review and critique

Although schools are among the safest places for children and youth, they are the occasional site of violent behavior. One form of violence is the barricaded-hostage event. In this article, the authors review the research literature pertaining to these events. Specifically, studies examining the impact on direct and indirect victims, and responders to these events, are presented and critiqued. Recommendations for future research are also made, followed by a summary and conclusions.