The effects of representations and behavior in experimental games

This research shows that in an experimental game it is the perception of an actual relationship, of an interaction with the other person more than the nature of the game which creates a climate in which cooperative responses can be established. Cooperative sets can be induced through the Representation of the partner: a reactive partner promoting cooperation, and a rigid one promoting competition. In addition it is noted that in order to understand the reactions induced by the partner's behavior, the behavior in itself it not sufficient. Indeed it is interpreted and understood in terms of the initial representation. The analysis of a person's behavior when in relation with another, should be based on a joint study of the existing representations and of the actual behavior observed.     

Methodological individualism in experimental games: not so easily dismissed

Orthodox game theory and social preference models cannot explain why people cooperate in many experimental games or how they manage to coordinate their choices. The theory of evidential decision making provides a solution, based on the idea that people tend to project their own choices onto others, whatever these choices might be. Evidential decision making preserves methodological individualism, and it works without recourse to social preferences. Rejecting methodological individualism, team reasoning is a thinly disguised resurgence of the group mind fallacy, and the experiments reported by Colman et al. [Colman, A. M., Pulford, B. D., & Rose, J. (this issue). Collective rationality in interactive decisions: Evidence for team reasoning. Acta Psychologica, doi:10.1016/j.actpsy.2007.08.003.] do not offer evidence that uniquely supports team reasoning.     

From a single-level analysis to a multilevel analysis of single-case experimental designs

Multilevel modeling provides one approach to synthesizing single-case experimental design data. In this study, we present the multilevel model (the two-level and the three-level models) for summarizing single-case results over cases, over studies, or both. In addition to the basic multilevel models, we elaborate on several plausible alternative models. We apply the proposed models to real datasets and investigate to what extent the estimated treatment effect is dependent on the modeling specifications and the underlying assumptions. By considering a range of plausible models and assumptions, researchers can determine the degree to which the effect estimates and conclusions are sensitive to the specific assumptions made. If the same conclusions are reached across a range of plausible assumptions, confidence in the conclusions can be enhanced. We advise researchers not to focus on one model but conduct multiple plausible multilevel analyses and investigate whether the results depend on the modeling options.     

Explaining individual differences in scholastic behaviour and achievement

Background. This paper presents results from the first wave of a longitudinal study examining the effects of various psychosocial variables on scholastic achievement and behaviour at school. Aims. The main aim is to investigate the nature and strength of the effects of major individual difference dimensions on important outcome variables at school level, including academic performance, truancy, and antisocial behaviour. Samples. Data were collected from a sample of 901 pupils on verbal ability (as a proxy for cognitive ability), personality traits, and a number of behavioural indices, including academic performance at 14 and 16 years, number of authorized and unauthorized absences, and exclusions from school due to antisocial conduct. Methods. During the first stage of the study, seven schools participated in all three phases. Teachers administered a questionnaire battery in class according to a detailed protocol. Additional data were collected from school archives. Results. Analysis of the data through multi‐group (male and female puplis) structural equation modelling indicated a very strong effect of verbal ability on academic performance. Extraversion and psychoticism were negatively related to academic performance, although their effects were weak and moderated by gender. Verbal ability, extraversion, and psychoticism predicted absenteeism, truancy, and exclusions from school due to disruptive conduct. The latter three were negatively associated with academic performance. Conclusions. The findings indicate that major individual difference dimensions like verbal ability and personality traits, have a strong influence on important outcome variables at school level, including academic performance, truancy, and antisocial behaviour. Without fully acknowledging the crucial role of individual differences in shaping behaviour and achievement at school, the timely identification of pupils at risk, and the development of effective intervention schemes will be difficult.     

Father-absence and scholastic performance in primary school children

The relationship between father-absence and academic achievement in children was studied in a sample of 80 urban children of predominantly lower social status. Differences between the father-absent and father-present groups in IQ and family background were controlled by matching. Boys and girls from father-present homes were found to score higher on standardized reading tests than children from father-absent homes, regardless of the child’s age when the father became absent. Mediating variables by which father-absence may exert its influence (achievement motivation, absenteeism, parental attitudes, sex-role identity, life stress) were also examined. Contrary to predictions, children from father-absent homes scored higher on achievement motivation measures than children from intact homes. Girls from father-absent homes missed more school and scored lower on tests of “masculinity” than girls raised in father-present homes. No other mediating variables exerted a significant influence on the results. These data are discussed in the light of the “confluence” theory of cognitive development. This study is part of a thesis submitted in partial fulfillment of the requirements of the M.A. degree by the senior author. Preparation of this article was assisted by a grant from the Australian Research Grants Scheme to the second author.     

Sex differences in scholastic aptitude: The Israeli scene

The major goal of the present study is two-fold: (a) To assess the direction, magnitude and profile of sex differences in scholastic aptitude test performance among Israeli college student candidates and (b) to test for possible sex bias in the construct validity of aptitude test scores. The analyses are based on the college admissions aptitude test scores of 1088 female and 690 male college candidates, applying for admissions to a major Israeli campus. On the whole, the data are consistent with much previous research, generated mainly from the American scene, showing small but consistent sex differences in favor of male examinees for the test as a whole and for the quantitative subscale, in particular. Also, the sex difference profiles for varying ethnic groups in the sample are surprisingly similar. Furthermore, our data show little evidence for differential construct validity of ability test scores by gender. On the whole, our data lend a greater degree of generality and cross-cultural validity to the bulk of previous research negating the sex bias contention and pointing to negligible gender differences in scholastic aptitude.     

From single-channel recordings to brain-mapping devices: the impact of electroencephalography on experimental psychology

Since its discovery in 1920, the electroencephalogram (EEG) has become a widely used tool in experimental psychology. Although originally the merits of the method were seen first of all in an improvement of medical diagnostics it was soon understood by psychologists that EEG can also be used to study psychic processes in healthy participants. This article summarizes important events in the history of EEG research that laid the ground for this development, as fast Fourier transformation to analyze the spontaneous activity and signal averaging to improve the signal-to-noise ratio. The article shows how general technological developments were the prerequisite for these methodological improvements in EEG research and how they inspired new research questions. Key discoveries that proved unequivocally that psychic processes do become manifest in EEG signals are briefly reviewed, and the emerging paradigm of cognitive psychophysiology, which is closely linked to the development of EEG research, is described.     

Individualistic attitudes toward attractive rewards in older people: An experimental study using ultimatum games

This study used an ultimatum game to test the hypothesis that older individuals make more selfish offers when bargaining for highly attractive rewards, regardless of the impacts of others' responses on reward size. Both older and younger individuals separately participated in the experiment and made offers as allocators. The effects of four factors (age, certainty of the allocators' own reward depending on the recipient's response, the recipient's response, and type of rewards to be shared) on participants' offers and expectations of recipients' replies were observed. Older participants demanded higher shares for themselves than younger participants, even under the low certainty condition in the highly attractive reward scenario. Particularly in this scenario, older participants increased their portions immediately after receiving rejections. Moreover, they consistently expected the recipients to accept their offers regardless of the proposed distribution amount or bargaining conditions. It was implied that the high attractiveness of the rewards made it difficult for older individuals to predict the recipient's view of their proposals and thus contributed to them making selfish proposals.     

When three is not always two against one: Coalitions in experimental three-person cooperative games

Four models of coalition formation are tested in a computer-controlled experiment in which three players negotiated to form coalitions in order to gain rewards for themselves. Formation of the grand coalition of all three players as well as any of the three possible 2-person coalitions is permitted. The results indicate that the grand coalition is the most likely to form, followed by the coalition between the two strongest players. The individually rational bargaining set model of coalition formation is supported over an egalitarian model, the Shapley value, and the coalitionally rational bargaining set model. Various measures of the progress of negotiations are introduced, examined, and discussed in an effort to provide an increased data base for the establishment of a behavioral theory of bargaining and coalition formation.