Age-related changes in decision making: comparing informed and noninformed situations

Advantageous decision making progressively develops into early adulthood, most specifically in complex and motivationally salient decision situations in which direct feedback on gains and losses is provided (Figner & Weber, 2011). However, the factors that underlie this developmental improvement in decision making are still not well understood. The current study therefore investigates 2 potential factors, long-term memory and working memory, by assigning a large developmental sample (7-29 years of age) to a condition with either high or low demands on long-term and working memory. The first condition featured an age-adapted version of the Iowa Gambling Task (IGT; Bechara, Damasio, Damasio, & Anderson, 1994; i.e., a noninformed situation), whereas the second condition provided an external store where explicit information on gains, losses, and probabilities per choice option was presented (i.e., an informed situation). Consistent with previous developmental IGT studies, children up to age 12 did not learn to prefer advantageous options in the noninformed condition. In contrast, all age groups learned to prefer the advantageous options in the informed conditions, although a slight developmental increase in advantageous decision making remained. These results indicate that lowering dependence on long-term and working memory improves children's advantageous decision making. The results additionally suggest that other factors, like inhibitory control processes, may play an additional role in the development of advantageous decision making.     

Effects of anxiety on the execution of police arrest and self-defense skills

We investigated the effects of anxiety on the execution of police officers' arrest and self-defense skills. Police officers (n=13) performed three tasks in which they kicked, blocked, or restrained an opponent who attacked them with a rubber knife (low anxiety, LA) or a shock knife (high anxiety, HA) in a within-subject design. We analyzed performance (on a 5-point Likert scale), movement times, posture, and movement velocity and acceleration. Results revealed that performance was worse in the HA compared to the LA condition. Furthermore, analysis of full-body movement showed that under increased anxiety, police officers' performance contained characteristics of avoidance behavior, such as faster reactions (to reduce the time being exposed to the threat), leaning further backward (kick), and ducking down (block). In line with recent theoretical developments, it appears that under increased anxiety, police officers were less able to inhibit stimulus-driven processing (fear of getting hit) and enforce goal-directed processing (perform the skill as well as possible) leading to avoidance behavior and a decrease in performance.     

Simulating the Impact During Human Jumping by Means of a 4-Degrees-of-Freedom Model With Time-Dependent Properties

The authors simulated the vertical movements of a jumper and the force time courses by means of a 4-degrees-of-freedom model consisting of 4 masses, springs, and dampers. Of the motions simulated, only that of the mass imitating the trunk corresponded to the measured data. The best fit to the measured force curves were obtained in the simulation in which time-dependent model parameters were used. From the results, the authors concluded that at the beginning of the landing, a jumper behaves like a 2-mass model in which the leg segments (thighs, shanks, and feet) effectively combine into 1 mass. After approximately 60 ms, the connections between the leg segments become more compliant and the jumper behaves like a 4-mass model with a soft coupling between the leg segments. The process is equivalent to an increase of the degrees of freedom of the movements. At the end of the ground contact phase during hopping, the jumper has to contract the muscles in order to reach the envisaged jump height. In the model, that contraction could not be satisfactorily simulated.     

Investigating the functioning of a middle category by means of a mixed-measurement model

Researchers have studied whether there are classes of people who differ systematically in the way they respond to polytomous ordered scales with a middle category such as ?. The mixed-partial credit model was fitted to a number of scales of a personality questionnaire. Most of the scales fit better with the use of 2 latent subpopulations. The most consistent difference among the latent classes was related to the functioning of the middle response category. For most of the examinees, the probability of choosing the middle category was very close to zero, but a nonnegligible percentage of people selected this category with much higher probability. The total scores from the 2 subpopulations were incommensurate. Some personality factors contributed to explaining class membership.     

Examining assumptions about item responding in personality assessment: should ideal point methods be considered for scale development and scoring?

The present study investigated whether the assumptions of an ideal point response process, similar in spirit to Thurstone's work in the context of attitude measurement, can provide viable alternatives to the traditionally used dominance assumptions for personality item calibration and scoring. Item response theory methods were used to compare the fit of 2 ideal point and 2 dominance models with data from the 5th edition of the Sixteen Personality Factor Questionnaire (S. Conn & M. L. Rieke, 1994). The authors' results indicate that ideal point models can provide as good or better fit to personality items than do dominance models because they can fit monotonically increasing item response functions but do not require this property. Several implications of these findings for personality measurement and personnel selection are described.     

Germ-line genetic enhancement and Rawlsian primary goods

Genetic interventions raise a host of moral issues and, of its various species, germ-line genetic enhancement is the most morally contentious. This paper surveys various arguments against germ-line enhancement and attempts to demonstrate their inadequacies. A positive argument is advanced in favor of certain forms of germ-line enhancements, which holds that they are morally permissible if and only if they augment Rawlsian primary goods, either directly or by facilitating their acquisition.     

An inferential approach to the knew-it-all-along phenomenon

Two studies tested the hypothesis that the knew-it-all-along effect may be the result of an inferential process. Specifically, that individuals use their feelings and experiences (e.g., "This question seems so familiar to me, surely I would have known the answer!") to infer their judgement. Drawing on subjective feelings such as certainty or perceptual fluency, individuals can use a provided actual value as an informational cue and draw inferences from it. Thus, the occurrence of the knew-it-all-along effect is expected to depend on the experienced feeling of confidence with a question. This feeling may indicate to an individual that he or she did know the answer; a total lack of such a feeling may suggest that he or she never would have known the answer. In the reported studies we both measured feelings of confidence (Study 1) and induced them by manipulating perceptual fluency (Study 2) to show that the knew-it-all-along effect proves to be a phenomenon of inferences based on these experienced feelings. Participants experiencing high confidence or high perceptual fluency more strongly assimilated their judgements to the provided values, than did participants experiencing low confidence or low perceptual fluency.     

Fact and Fiction in Implicit Personality Theory

ABSTRACT This article reports two studies, where the accuracy of implicit personality theory (IPT) was investigated using on-line behavior counts as well as retrospective frequency estimates as standards of comparison Eight discussion groups, each comprising six members, were videotaped Their act frequencies with respect to 16 types of behavior were judged on-line using two coding schemes, each one being applied by two independent raters Five other judges estimated the act frequencies retrospectively Furthermore, judges revealed their IPT by estimating the conditional likelihood of these types of behavior It turned out that (a) retrospective judges perceive different base rates accurately, (b) the correlations among retrospectively estimated and among on-line recorded act frequencies show high correspondences, (c) IPT accurately mirrors the correlations among retrospectively estimated as well as among on-line recorded act frequencies, and (d) judges do not appropriately consider perceived base rates when estimating conditional probabilities It is concluded that IPT is considerably accurate in those respects that are important for the validity and structural fidelity of personality ratings     

Early gender differences in the functional usage of language

Early male and female differences in the functional use of language were investigated by coding the verbal interactions of 32 preschool children during a 10-minute play session with same-sex peer. The speech of each child was classified into functional-motivational categories using the FIS-P scoring instrument. The findings were consistent with the literature on adult conversational styles, showing that males talk more and are more assertive in their social interactions than are females. The results of this study demonstrate the existence of early gender differences in the functional use of language and emphasize the importance of a developmental approach to the study of communication styles.     

Rasch's model for reading speed with manifest explanatory variables

In educational and psychological measurement we find the distinction between speed and power tests. Although most tests are partially speeded, the speed element is usually neglected. Here we consider a latent trait model developed by Rasch for the response time on a (set of) pure speed test(s), which is based on the assumption that the test response times are approximately gamma distributed, with known shape parameters and scale parameters depending on subject ability and test difficulty parameters. In our approach the subject parameters are treated as random variables having a common gamma distribution. From this, maximum marginal likelihood estimators are derived for the test difficulties and the parameters of the latent subject distribution. This basic model can be extended in a number of ways. Explanatory variables for the latent subject parameters and for the test parameters can be incorporated in the model. Our methods are illustrated by the analysis of a simulated and an empirical data set.