On the existence and uniqueness of JML estimates for the partial credit model

A necessary and sufficient condition is given in this paper for the existence and uniqueness of the maximum likelihood (the so-called joint maximum likelihood) estimate of the parameters of the Partial Credit Model. This condition is stated in terms of a structural property of the pattern of the data matrix that can be easily verified on the basis of a simple iterative procedure. The result is proved by using an argument of Haberman (1977). The author wishes to thank the Editor and the anonymous reviewers for their comments that helped to substantially improve the final version of this paper. This research was supported in part by a MURST grant (ex 60%).     

Geometric orientation by humans: angles weigh in

Human participants were trained to navigate to two geometrically equivalent corners of a parallelogram-shaped virtual environment. The unique shape of the environment combined three distinct types of geometric information that could be used in combination or in isolation to orient and locate the goals: the angular amplitudes of the corners, the relative wall length relationships, and the principal axis of symmetry. In testing, participants were placed in manipulated versions of the training environment that tested which types of geometry they had encoded and how angular information weighed in against the other two geometric properties. The test environments were (a) a rectangular environment that removed the angular information, (b) a rhombic environment that removed wall length information and drastically reduced the principal axis, and (c) a reverse-parallelogram-shaped environment that placed angular information against both wall length and principal axis information. Participants chose accurately in the rectangular and rhombus environments, despite the removal of one of the cues. In the conflict test, participants preferred corners with the correct angular amplitudes over corners that were correct according to both wall length relationships and the principal axis. These results are comparable to recent findings with pigeons and suggest that angles are a salient orientation cue for humans.     

Media use and school achievement – boys at risk?

In work done at the German Criminological Research Institute of Lower Saxony (KFN) various methods have been used to investigate how specific inappropriate media usage patterns affect academic performance in children and adolescents. The findings are paralleled by current international research indicating a negative relationship between these two variables. Based on a cross‐sectional survey of 5,529 fourth grade students and a longitudinal panel study with 1,157 primary schoolchildren, a key finding can be demonstrated: the more time students spend on consuming media and the more violent its contents are, the worse are their marks at school, even when controlling for vital factors such as family, educational, or immigrant background. In particular, boys who gender‐specifically are better equipped with electronic media devices, who partially have extensive media usage times and who strongly prefer violent media content, are at the risk of showing poor school performance. In fact, a decrease in academic performance of boys can be observed in German school statistics. By presenting first results of a school‐based intervention programme, a promising approach to the reduction of detrimental effects of electronic media use on school performance is introduced.     

Dichhaptic hand-order effects with verbal and nonverbal tactile stimulation

The palms of normal right-handed subjects were stimulated dichhaptically, i.e., with competing, bimanually presented tactile stimuli consisting of pairs of letters, pairs of digits, or pairs of line orientations. The subjects were required to identify both stimuli in a particular order, and order of report was compared between hands and across stimulus materials. Results indicated right-hand superiority for letters and left-hand superiority for lines; no hand differences occurred for digits. However, observed differences between hands appeared with second reports only, suggesting that measures of tactile storage are more sensitive to laterality differences than measures closer in time to actual stimulation.     

Validity of the Inventory of Interpersonal Problems (IIP–64) for Predicting Assertiveness in Role-Play Situations

The Buddhist notion of “nonattachment” (release from mental fixations) is related to but distinguishable from the Western construct of attachment. Secure (or insecure) attachment is based on internal working models related to security (or insecurity), whereas nonattachment is based on insight into the constructed and impermanent nature of mental representations. Based on historical and contemporary Buddhist scholarship, we designed the Nonattachment Scale and evaluated its psychometric properties in various samples. We also present evidence consistent with Buddhist theory that nonattachment is psychologically and socially adaptive, and we offer directions for further research on nonattachment.     

Silicon in ‘pure gold’? Theoretical contributions and observations on teleanalysis by videoconference

Ideas about psychoanalysis via videoconference—videoconference teleanalysis (VT)—are presented with the general understanding that these settings produce a twofold split between various degrees of recognition/negativisation of the absence of the other, on one hand, and the expectation of physical co‐presence, on the other. This split has been put forward as dismantling the here, now, with me pre‐reflexive unity of the analytic experience. This article suggests that both members of the analytic dyad will seek to reappropriate the experience through a forced ego integration that interferes with accessing states of unintegration in the analytic treatment and produces subtle alterations to symbolisation work. The effort to overcome this condition is illustrated with clinical vignettes and therapists’ comments about feelings of inauthenticity and discontent when trying to sustain evenly‐suspended attention, as well as in the perception of a form of flattening of the alive nature of speech. However, this is not a constant for all VT, and mutual understanding can be an important mitigating feature. The focus of the discussion should be on the capacity of the analytic dyad to overcome such a split and not on a direct extrapolation of the perceptual limitations of VT to possible effects on transference / countertransference.     

Searching for Spiritual Signatures in SETI Research

The Search for Extraterrestrial Intelligence (SETI) research assumes that we live in an intelligence-friendly universe. But do we live in a spiritual-friendly universe? We include the spiritual quest in a new multidisciplinary approach to SETI. In a thought experiment, we consider two types of alien civilizations by including a Spiritual factor in the Drake Equation. Using the analogy of planetary biomarkers and the concept of noosphere introduced by Teilhard de Chardin, we propose two spiritual markers that could evidence the presence of a noosphere in an exoplanet.     

Visual attention in adolescents: Facilitating effects of sport expertise and acute physical exercise

ObjectivesThis study investigated visual attention of adolescent orienteers and physically active adolescents non-practising orienteering both at rest and under acute sub-maximal exercise. It was verified whether the practice of orienteering facilitates the development of visual attentional abilities and whether orienteers, who are used to simultaneously handle physiological and cognitive-attentional loads, may better profit than non-orienteers from the beneficial effects of sub-maximal physical load on processing speed.MethodsBoth the focusing of attention at foveal and parafoveal locations and the orienting of attention at peripheral locations were investigated. In two discriminative reaction time (RT) experiments, a cue of varying size was presented centrally or peripherally and followed by a compound stimulus with local and global target features. The stimulus-onset asynchrony (SOA) varied between a short and a long interval.ResultsIn both experiments, adolescent orienteers and non-practisers showed different patterns of attentional effects. Adolescent orienteers were more similar to young adults in the attentional performance, being better able than non-practisers to perform complex attentional operations involving the intentional zooming of attention in the central visual field and the orienting of the attentional focus in the peripheral visual field. Also, both orienteers and non-orienteers speeded up their performance during exercise, but this facilitation effect was more pronounced for orienteers, who are probably skilled in directing the available resources to task demands.ConclusionsOur results suggest that cognitive expertise represents a key factor in sports that accelerates the development of visual attention and enhances the facilitating effects of physical exercise on attentional performance.