Planning abilities and chess: A comparison of chess and non‐chess players on the Tower of London task

Playing chess requires problem‐solving capacities in order to search through the chess problem space in an effective manner. Chess should thus require planning abilities for calculating many moves ahead. Therefore, we asked whether chess players are better problem solvers than non‐chess players in a complex planning task. We compared planning performance between chess (N=25) and non‐chess players (N=25) using a standard psychometric planning task, the Tower of London (ToL) test. We also assessed fluid intelligence (Raven Test), as well as verbal and visuospatial working memory. As expected, chess players showed better planning performance than non‐chess players, an effect most strongly expressed in difficult problems. On the other hand, they showed longer planning and movement execution times, especially for incorrectly solved trials. No differences in fluid intelligence and verbal/visuospatial working memory were found between both groups. These findings indicate that better performance in chess players is associated with disproportionally longer solution times, although it remains to be investigated whether motivational or strategic differences account for this result.     

Revising superior planning performance in chess players: the impact of time restriction and motivation aspects

In a previous study (Unterrainer, Kaller, Halsband, & Rahm, 2006), chess players outperformed non-chess players in the Tower of London planning task but exhibited disproportionately longer processing times. This pattern of results raises the question of whether chess players' planning capabilities are superior or whether the results reflect differences in the speed-accuracy trade-off between the groups, possibly attributable to sports motivation. The present study was designed to disambiguate these alternative suggestions by implementing various constraints on planning time and by assessing self-reported motivation. In contrast to the previous study, chess players' performance was not superior, independently of whether problems had to be solved with (Experiment 1) or without (Experiment 2) time limits. As expected, chess players reported higher overall trait and state motivation scores across both experiments. These findings revise the notion of superior planning performance in chess players. In consequence, they do not conform with the assumption of a general transfer of chess-related planning expertise to other cognitive domains, instead suggesting that superior performance may be possible only under specific circumstances such as receiving competitive instructions.     

Sex differences in intellectual performance: analysis of a large cohort of competitive chess players

Only 1% of the world's chess grandmasters are women. This underrepresentation is unlikely to be caused by discrimination, because chess ratings objectively reflect competitive results. Using data on the ratings of more than 250,000 tournament players over 13 years, we investigated several potential explanations for the male domination of elite chess. We found that (a) the ratings of men are higher on average than those of women, but no more variable; (b) matched boys and girls improve and drop out at equal rates, but boys begin chess competition in greater numbers and at higher performance levels than girls; and (c) in locales where at least 50% of the new young players are girls, their initial ratings are not lower than those of boys. We conclude that the greater number of men at the highest levels in chess can be explained by the greater number of boys who enter chess at the lowest levels.     

Statistical inference in generalized linear mixed models: A review

We present a review of statistical inference in generalized linear mixed models (GLMMs). GLMMs are an extension of generalized linear models and are suitable for the analysis of non‐normal data with a clustered structure. A GLMM contains parameters common to all clusters (fixed regression effects and variance components) and cluster‐specific parameters. The latter parameters are assumed to be randomly drawn from a population distribution. The parameters of this population distribution (the variance components) have to be estimated together with the fixed effects. We focus on the case in which the cluster‐specific parameters are normally distributed. The cluster‐specific effects are integrated out of the likelihood so that the fixed effects and variance components can be estimated. Unfortunately, the integral over the cluster‐specific effects is intractable for most GLMMs with a normal mixing distribution. Within a classical statistical framework, we distinguish between two broad classes of methods to handle this intractable integral: methods that rely on a numerical approximation to the integral and methods that use an analytical approximation to the integrand. Finally, we present an overview of available methods for testing hypotheses about the parameters of GLMMs.     

Academic self‐handicapping: Relationships with learning specific and general self‐perceptions and academic performance over time

Background. Academic self‐handicapping (ASH) tendencies, strategies students employ that increase their chances of failure on assessments while protecting self‐esteem, are correlated with classroom goal structures and to learners' general self‐perceptions and learning strategies. In particular, greater ASH is related to poorer academic performance but has yet to be examined with respect to learners' performance across a series of tests. Aims. This research was designed to examine the relationship between students' ASH tendencies and their self‐concept clarity, learning strategies, and performance on a series of tests in a university course. Sample. A total of 209 (153 female; 56 male) Canadian university psychology students participated in this study. Methods. Participants' ASH tendencies, self‐concept clarity, approaches to learning, and self‐regulatory learning strategies were assessed along with expected grades and hours of study in the course from which they were recruited. Finally, students' grades were obtained for the three tests for the course from which they were recruited. Results. Students reporting greater self‐handicapping tendencies reported lower self‐concept clarity, lower academic self‐efficacy, greater test anxiety, more superficial learning strategies, and scored lower on all tests in the course. The relationships of ASH scores and learner variables with performance varied across the three performance indices. In particular, ASH scores were more strongly related to second and third tests, and prior performances were accounted for. ASH scores accounted for a relatively small but significant proportion of variance for all three tests. Conclusions. These results showed that ASH is a unique contributing factor in student performance outcomes, and may be particularly important after students complete the initial assessment in a course.     

Linked linear mixed models: A joint analysis of fixation locations and fixation durations in natural reading

The complexity of eye-movement control during reading allows measurement of many dependent variables, the most prominent ones being fixation durations and their locations in words. In current practice, either variable may serve as dependent variable or covariate for the other in linear mixed models (LMMs) featuring also psycholinguistic covariates of word recognition and sentence comprehension. Rather than analyzing fixation location and duration with separate LMMs, we propose linking the two according to their sequential dependency. Specifically, we include predicted fixation location (estimated in the first LMM from psycholinguistic covariates) and its associated residual fixation location as covariates in the second, fixation-duration LMM. This linked LMM affords a distinction between direct and indirect effects (mediated through fixation location) of psycholinguistic covariates on fixation durations. Results confirm the robustness of distributed processing in the perceptual span. They also offer a resolution of the paradox of the inverted optimal viewing position (IOVP) effect (i.e., longer fixation durations in the center than at the beginning and end of words) although the opposite (i.e., an OVP effect) is predicted from default assumptions of psycholinguistic processing efficiency: The IOVP effect in fixation durations is due to the residual fixation-location covariate, presumably driven primarily by saccadic error, and the OVP effect (at least the left part of it) is uncovered with the predicted fixation-location covariate, capturing the indirect effects of psycholinguistic covariates. We expect that linked LMMs will be useful for the analysis of other dynamically related multiple outcomes, a conundrum of most psychonomic research.     

The lone gamer: Social exclusion predicts violent video game preferences and fuels aggressive inclinations in adolescent players

Violent video game playing has been linked to a wide range of negative outcomes, especially in adolescents. In the present research, we focused on a potential determinant of adolescents’ willingness to play violent video games: social exclusion. We also tested whether exclusion can predict increased aggressiveness following violent video game playing. In two experiments, we predicted that exclusion could increase adolescents’ preferences for violent video games and interact with violent game playing fostering adolescents’ aggressive inclinations. In Study 1, 121 adolescents (aged 10–18 years) were randomly assigned to a manipulation of social exclusion. Then, they evaluated the violent content of nine different video games (violent, nonviolent, or prosocial) and reported their willingness to play each presented video game. The results showed that excluded participants expressed a greater willingness to play violent games than nonviolent or prosocial games. No such effect was found for included participants. In Study 2, both inclusionary status and video game contents were manipulated. After a manipulation of inclusionary status, 113 adolescents (aged 11–16 years) were randomly assigned to play either a violent or a nonviolent video game. Then, they were given an opportunity to express their aggressive inclinations toward the excluders. Results showed that excluded participants who played a violent game displayed the highest level of aggressive inclinations than participants who were assigned to the other experimental conditions. Overall, these findings suggest that exclusion increases preferences for violent games and that the combination of exclusion and violent game playing fuels aggressive inclinations.

     

Children's sleep and cognitive performance: a cross-domain analysis of change over time

Relations between changes in children's cognitive performance and changes in sleep problems were examined over a 3-year period, and family socioeconomic status, child race/ethnicity, and gender were assessed as moderators of these associations. Participants were 250 second- and third-grade (8-9 years old at Time 1) boys and girls. At each assessment, children's cognitive performance (Verbal Comprehension, Decision Speed) was measured using the Woodcock-Johnson III Tests of Cognitive Abilities, and sleep problems (Sleepiness, Sleep/Wake Problems) were collected via self-report. Individual growth models revealed that children who reported increases in Sleepiness exhibited little growth in Verbal Comprehension over time compared with their peers who reported decreases in Sleepiness, resulting in a nearly 11-point cognitive deficit by the end of the study. These associations were not found for Sleep/Wake Problems or Decision Speed. Child race/ethnicity and gender moderated these associations, with Sleepiness serving as a vulnerability factor for poor cognitive outcomes, especially among African American children and girls. Differences in cognitive performance for children with high and low Sleepiness trajectories ranged from 16 to 19 points for African American children and from 11 to 19 points for girls. Results build substantially on existing literature examining associations between sleep and cognitive functioning in children and are the first to demonstrate that children's sleep trajectories over 3 waves were associated with changes in their cognitive performance over time.     

Deliberate Self‐Harm in Adolescents Aged 12–18: A Cross‐Sectional Survey of 18,104 Students

Little is known about accurate prevalence and associated factors of deliberate self‐harm (DSH) among adolescents in Asian countries. In this study, the prevalence and associated factors of DSH among adolescents in Japan were examined. Data were derived from a cross‐sectional survey using an anonymous self‐report questionnaire and enrolling 8,620 adolescents aged 12–15 and 9,484 aged 15–18. DSH in the previous 12 months was reported by 3.3% (95% CI, 2.9–3.7) of junior and 4.3% (3.9%–4.7%) of senior high school respondents. The prevalence was more than four times as high among girls as among boys for both age groups. DSH was further strongly associated with having suicidal thoughts, having depression/anxiety symptoms, and having used recreational drugs. These associated factors were similar for both sexes and for both older and younger teenagers. A substantial minority of adolescents present with DSH, even among those aged 12–15. The prevalence of DSH in Japan was in the lower ranges of those reported for Western countries. The identified associated factors were not dissimilar from those reported in the West.     

A comparison of statistical selection strategies for univariate and bivariate log‐linear models

In this study, eight statistical selection strategies were evaluated for selecting the parameterizations of log‐linear models used to model the distributions of psychometric tests. The selection strategies included significance tests based on four chi‐squared statistics (likelihood ratio, Pearson, Freeman–Tukey, and Cressie–Read) and four additional strategies (Akaike information criterion (AIC), Bayesian information criterion (BIC), consistent Akaike information criterion (CAIC), and a measure attributed to Goodman). The strategies were evaluated in simulations for different log‐linear models of univariate and bivariate test‐score distributions and two sample sizes. Results showed that all eight selection strategies were most accurate for the largest sample size considered. For univariate distributions, the AIC selection strategy was especially accurate for selecting the correct parameterization of a complex log‐linear model and the likelihood ratio chi‐squared selection strategy was the most accurate strategy for selecting the correct parameterization of a relatively simple log‐linear model. For bivariate distributions, the likelihood ratio chi‐squared, Freeman–Tukey chi‐squared, BIC, and CAIC selection strategies had similarly high selection accuracies.     

Examining time‐invariance in reliability in multi‐wave,multi‐indicator models: A covariance structure analysis approach accounting for indicator specificity

A covariance structure analysis method for testing time‐invariance in reliability in multiwave, multiple‐indicator models in outlined. The approach accounts for observed variable specificity and permits, in addition, estimation of reliability in terms of ‘pure’ measurement error variance. The proposed procedure is developed within a confirmatory factor analysis framework and illustrated with data from a cognitive intervention study.     

A hierarchical linear modeling assessment of dual-addiction status and change in sexual compulsivity over time

This study examined the association between dual-addiction status and sexual compulsivity over time in a sample of self-identified sexually compulsive males. Hierarchical linear modeling was utilized to address the study's research questions. Dually addicted sexually compulsive males exhibited lower rates of sexual compulsivity than their singularly addicted counterparts initially but displayed less precipitous declines in sexual compulsiveness over time. Implications for treatment providers are discussed.     

Women in popular music: A quantitative analysis of feminine images over time

Popular song lyrics from the years 1946, 1956, 1966, and 1976, were content analyzed for feminine images. Eleven stereotyped female images were examined: woman as evil; emphasis on physical characteristics; woman's need for man; woman as a possession of man; woman as mother; woman as sex object; woman as delicate; woman as child; woman on a pedestal; woman as physically attractive; and woman as supernatural. Significant changes over time were found for 8 of the 11 images. Of the songs sampled from 1946–1976, 96% contained at least one of the female stereotypes examined in this investigation.     

Real‐time performance monitoring,goal‐setting,and feedback for forklift drivers in a distribution centre

In this study conducted in two auto‐parts after‐market distribution centres, immediate performance goals and feedback were delivered to employees in a warehouse on wireless vehicle‐mounted computers. Engineered labour standards (ELS) calculated work‐unit goal times and presented the driver with immediate performance feedback. Ultimately, the ELS feedback was linked to the company's forklift driver team pallet‐per‐hour quota achievement. Replenishment performance for forklift drivers (N=12) was improved by 2.14 pallets per hour when an intervention package that included the depiction of goal times and immediate performance feedback on wireless vehicle‐mounted computers and a newly developed ELS. The implications of these findings, limitations, and safety issues are discussed in terms of operational issues regarding ELS in large industrial settings.     

Intimacy in young adults' narratives of romance and friendship predicts Eriksonian generativity: a mixed method analysis

A quantitative and qualitative study tested Erikson's ego developmental hypotheses regarding the positive relationship between generativity and intimacy. At age 26, participants (N = 100) told 2 stories about "relationship-defining moments," one about a romantic partner, and another about a same-sex friend. Levels of relationship intimacy were coded from these narratives. "True love" and "true friendship" themes arose as the most prototypical, highly intimate stories. Romantic intimacy and friendship intimacy as coded from narratives each contributed uniquely to the prediction of generative concern; as intimacy in each domain increased, so did generative concern. This relationship remained statistically significant, even when controlling for gender, current romantic relationship status, subjective well-being, optimism, and depressive symptoms. Results suggest that our "relationship-defining moment" narrative task is a useful tool for examining development in emerging adulthood and that intimacy may be an important precursor to generative concern in early adulthood, consistent with Erikson's model.     

A threat in the elder: the impact of task‐instructions,self‐efficacy and performance expectations on memory performance in the elderly

Widely used explicit memory tasks seem to overestimate age‐related differences in memory performance. Social and personal factors may buffer or undermine the effect of age on memory performance. In two studies, the performance of older adults was compared with the performance of younger adults. Tasks were presented either as memory tasks or non‐memory tasks. Older adults' performance on a memory task improved when the task‐instructions did not explicitly emphasize the memory component of the task. In the first study, results revealed that memory self‐efficacy beliefs play a moderator role on the impact of task‐instruction on memory performance, so that lower levels of memory self‐efficacy correlate with lower performance in the memory emphasizing task condition but not in the orientation emphasizing task condition. In a second study actual performance expectations were measured. For older participants only, expectations were sensitive to task‐instructions and mediated the relation between tasks‐instructions and performances. These findings suggest that observed age‐related differences in memory performance may be significantly exaggerated by the testing situation and by a low memory self‐efficacy and low memory performance expectancies prevalent among older adults. Copyright © 2005 John Wiley & Sons, Ltd.     

A multilevel analysis of effort, practice, and performance: effects; of ability, conscientiousness, and goal orientation

This article examines the relationship between motivation and performance during skill acquisition. The authors used multilevel analysis to investigate relationships at within- and between-person levels of analysis. Participants were given multiple trials of practice on an air traffic control task. Measures of effort intensity and performance were taken at repeated intervals. As expected, the relationship between effort and performance increased with practice. Furthermore, the rate at which this effect strengthened was faster for individuals with high-ability or low-performance orientation. There was also an interaction between learning and performance orientations that only emerged after practice. By the end of practice, the negative effects of performance orientation were stronger for individuals with high learning orientation. Results highlight the importance of adopting a multilevel framework to enhance understanding of the link between motivation and performance.