The generalized universal law of generalization

It has been argued by Shepard that there is a robust psychological law that relates the distance between a pair of items in psychological space and the probability that they will be perceived as similar. Specifically, this probability is a negative exponential function of the distance between the pair of items. In experimental contexts, distance is typically defined in terms of a multidimensional space—but this assumption seems unlikely to hold for complex stimuli. We show that, nonetheless, the Universal Law of Generalization can be derived in the more complex setting of arbitrary stimuli, using a much more universal measure of distance. This universal distance is defined as the length of the shortest program that transforms the representations of the two items of interest into one another: The algorithmic information distance. It is universal in the sense that it minorizes every computable distance: It is the smallest computable distance. We show that the Universal Law of Generalization holds with probability going to one—provided the probabilities concerned are computable. We also give a mathematically more appealing form of the Universal Law.     

Using image analysis techniques to analyze figure-copying performance of patients with visuospatial neglect and control groups.

Figure copying is often used to detect visuospatial neglect (VSN) in brain-damaged patients. We describe algorithms that enable the computation of parameters for describing figure-copying performance. The researcher can readily implement these algorithms on a computer using image analysis software, and they provide information on goodness-of-fit, relative to a standard model, as well as on dynamic aspects of subjects' performance in completing figure copies. To demonstrate the clinical utility of these algorithms, preliminary results from a group of right-hemisphere brain-damaged patients, some of whom have VSN, are compared with those for age-matched controls.     

The role of social categorization and identity threat in the perception of migrants

This paper investigates how the categorization of migrant workers shapes their reception. In an experiment with Northern Irish Protestants we manipulated the representation of Poland to make the Catholicism of Polish migrants either more, or less, salient. Furthermore, judgements of Polish migrants were obtained under conditions designed to encourage participants to believe that sectarian conflict in Northern Ireland was either resolved, or still a strong feature of the present social landscape. Overall, results showed that when Poland's Catholicism was salient, participants were less welcoming of Polish migrants. Furthermore, this effect was mediated by increases in the level of symbolic threat participants believed the migrants posed to participants' (Protestant) community identity. Copyright © 2009 John Wiley & Sons, Ltd.     

PsychoPro 2.0: Using multidimensional scaling to examine the perceptual categorization of race

Recently, researchers examining cognitive mechanisms involved in the detection of racial markers have been using psychophysics to examine perceptual thresholds delineating race using a program called PsychoPro (MacLin, MacLin, Peterson, Chowdhry, & Joshi, 2009). PsychoPro allows researchers to collect data using facial stimuli morphed along a racial continuum with psychophysical methodology. PsychoPro 2.0 was updated so researchers could collect paired-comparison data that can then be analyzed using multidimensional scaling (MDS). MDS allows researchers to examine the perceptions of racial boundaries along perceptual dimensions not bounded by the stimulus continuum, by having the observer make paired comparisons to racial stimuli based on their perceived similarity. Results indicate that ratings were made on the basis of at least six different racial dimensions that suggest the emergence of a third race not represented by the original morph starting images. Details of the software, the new paired-comparison feature and its relevance in psychophysical studies in general and racial categorization in particular are presented.     

Cognitive models of stereotype change (4): Motivational and cognitive influences

Three experiments investigating the effects of cognitive and motivational factors on stereotype change are reported. Trait ratings in all three experiments showed there to be greater stereotype-change when stereotype-inconsistent information was dispersed across many group members than when it was concentrated in only a few. A sorting task (Experiment 1) indicated that, in the concentrated conditions the stereotype disconfirmers were more strongly isolated from the rest of the group than in the dispersed conditions. Free recall protocols (Experiment 2) showed greater memory for the target exemplars when subjects anticipated interaction with a group member than when no interaction was anticipated. The questions subject chose to ask target group exemplars were also influenced by anticlpated future interaction. Subjects chose more stereotype-inconsistent questions when interactian was anticipated than when no interaction was anticipated. Experment 3 showed the impact of stereotype-inconsistent information to be greater when expectancies for the stereotyped group are weaker A cued-recall task yielded evidence of spontaneous subtyping. All these studies support the subtyping model, even in the presence of cognitive and motivational factors that might be expected to impede stereotype change.     

The significance of self-reported anxious symptoms in first-grade children

It is generally believed that prior to the middle to late elementary school years children's reports of anxious symptoms represent nothing more than transient developmental phenomena. In light of the limited empirical study of this issue and its import to the allocation of mental health resources, the present study seeks to provide empirical evidence of the significance of anxious symptoms in children younger than 7. Specifically, utilizing an epidemiologically defined population of 1197 first-grade children, followed longitudinally from the fall to spring of first grade, we examine the stability, prevalence and caseness of children's self-reports of anxious symptoms. Self-reported anxious symptoms proved relatively stable over 4-month test-retest interval. In addition, they appeared to have a significant impact on academic functioning in terms of reading achievement. These findings on stability, caseness, and prevalence suggest children's self-reported anxious symptoms in the early elementary school years may have clinical significance. However, further study is necessary before firm conclusions can be drawn.     

Process and content in a long-term PTSD therapy group for Vietnam veterans

Process and content were studied in four 16-session segments of a psychodynamically oriented therapy group for Vietnam veterans suffering from posttraumatic stress disorder (PTSD). On the Group Climate Questionnaire (GCQ-S), the group scored significantly higher in the Engaged dimension and significantly lower in the Avoiding and Conflict dimensions than contrasting samples of neurotic and psychotic groups. There was no evidence of group stages. Topics related to symptoms of PTSD were discussed most frequently (43.1%), followed by issues concerning relations with others (32.4%),general group therapy issues (13.7%), and other topics (10.8%). Clinical implications of these findings are discussed.The authors thank Tom Metzler, M.A., and Heidi Ronfeldt, B.S., for their assistance with the data analysis.Parts of this paper were presented at the American Group Psychotherapy Association Annual Meeting, February 15–20, 1993, San Diego, CA.     

School pupils' perceptions of the police that visit schools: Not all police are ‘pigs’

This paper presents data concerning young people's perceptions of the police taking part in a police—schools liaison programme. Eighty-one 14-year-old school pupils took part in 28 semi-structured group discussions concerning their perceptions of the ‘typicality’ of police officers working in their schools. Pupils clearly differentiated between these and those ‘on the street’. Central to this differentiation was the issue of police power; the perceived atypicality of the police in schools was intimately bound up with pupils' perceptions of the qualitatively different social relations that obtain between young people and the police ‘in the school’ and ‘on the street’. The implications of these data for the literatures concerning the ‘contact hypothesis’ and police—schools liaison are discussed.     

Beyond the qualitative paradigm: A framework for introducing diversity within qualitative psychology

The case for qualitative research in psychology is considered. We argue against the idea that qualitative research is merely a matter of technique or method, and question the utility of viewing it as a unitary paradigm. Rather, the links between epistemology, methodology, and method are explored within three theorized strands of qualitative inquiry, making reference to illustrative projects. Each strand is organized around a different approach to the issues of justifying and warranting psychological knowledge: (1) reliability and validity; (2) generativity and grounding; and (3) discourse and reflexivity. These are exemplified in Miles and Huberman's ‘data display’ model, Glaser and Strauss' method of ‘grounded theory’, and in various forms of ‘discourse’ analysis. Reflections upon points of contact between the three strands address two main issues: (1) rendering research publicly accountable; and (2) challenging relativism.