Strategies of rule discovery in an inference task

It has long been known that subjects in certain inference tasks will seek evidence which can confirm their present hypotheses, even in situations where disconfirmatory evidence could be more informative. We sought to alter this tendency in a series of experiments which employed a rule discovery task, the 2-4-6 problem first described by Wason. The first experiment instructionally modified subjects confirmatory tendencies. While a disconfirmatory strategy was easily induced, it did not lead to greater efficiency in discovering the rule. The second experiment introduced subjects to the possibility of disconfirmation only after they had developed a strongly held hypothesis through the use of confirmatory evidence. This manipulation also failed to alter the efficiency of rule discovery. In the third experiment, subjects were taught to use multiple hypotheses at each step, in the manner of Platt's “Strong Inference”. This operation actually worsened performance. Finally, in the fourth experiment, the structure of the problem was altered slightly by asking subjects to seek two interrelated rules. A dramatic increase in performance resulted, perhaps because information which in previous tasks was seen as merely erroneous could now be related to an alternative rule. The four studies have broad implications for the psychological study of inference processes in general, and for the study of scientific inference in particular.     

Asia-Pacific prevention research. CHallenges, opportunities, and implementation

An effort is underway in the Asia-Pacific region to carry out multidisciplinary prevention research, with an emphasis on understanding health-related behaviors. In partnerships with the U.S. Centers for Disease Control, the U.S. Public Health Service, international health agencies, governments, and universities in the region, researchers at the University of Hawaii are pursuing a paradigm for international, multicultural prevention research in the field of health promotion and disease prevention. An integrated framework for guiding a program of research is discussed along with several factors that present challenges to the conduct of prevention research in the Asia-Pacific region.     

Gender role typing,the superwoman ideal,and the potential for eating disorders

The interactive effects of gender role typing and adherence to a superwoman ideal (desiring to excel in many diverse roles) on the potential for disordered eating were examined among a nonclinical sample of women. Results indicated that both masculine and feminine gender-typed women who strongly adhered to a superwoman ideal were at greater risk for eating disorders than androgynous superwomen. In contrast, androgynous superwomen had relatively low potential for disordered eating and appeared comparable to women who, regardless of gender typing, rejected the superwoman ideal. Women undifferentiated with regard to gender type, whether superwomen or not, also had reduced potential for disordered eating. Findings are discussed with regard to gender role socialization and expectations, and the implications for mediating the potential for eating disorders are considered.     

Predictive testing for HD: maximizing patient autonomy

In "The Ethical Justification for Minimal Paternalism in the Use of the Predictive Test for Huntington's Disease," David DeGrazia attempts to provide a rational analysis of the exclusion criteria and counseling requirements for predictive testing proposed by the Huntington's Disease Society of America (HDSA). The need for analysis is clear. These protocols and procedures for predictive testing for Huntington's disease (HD) are being used as models for testing programs for any number of genetic conditions. DeGrazia concludes that the HDSA guidelines are reasonable, a conclusion with which I agree. However, I believe that DeGrazia, by placing his analysis within the framework of autonomy versus paternalism, overlooks both the fundamental rationale for the testing procedures and the true barriers to testing....The difficulties encountered during the testing process clearly demonstrated the failure of abstract principles to deal with real life.     

Assessment of delusional beliefs during the modification of delusional verbalizations

This study examined the strength of delusional beliefs during the modification of delusional verbalizations of a 51 year-old chronically mentally ill inpatient. The changing-criterion design was used to document the effectiveness of a behavioral treatment package to alter the rate of delusional responses to personal background questions. The results revealed a stepwise decline in the frequency of delusional responses. Generalization effects to novel interviewers were obtained. No changes were obtained on the subject's ratings of delusional beliefs, with the subject assigning ratings of absolute conviction to his beliefs throughout the duration of the study.     

A computerized infrared monitor for following movement in aquatic animals

Reliable monitoring of the movement of small aquatic animals presents some unique problems. In the case of the larval salamander, the animal may be less than an inch long and move in sporadic short bursts. A device is described that utilizes infrared emitters and wide-band sensors inter-faced to a computer for monitoring location and movement of animals between light and dark environments over extended periods of time. The system employs a multiplexed digital input, is inexpensive, and can be easily expanded to deal with a range of monitoring problems that may occur with a wide range of both aquatic and terrestrial species.     

Biculturalism,Locus of Control,and Leader Behavior in Ethnically Mixed Small Groups1

The study examined the interactive effects of degree of biculturalism and locus of control on leader behavior in supportive and nonsupportive ethnically mixed small groups. Subjects were 36 male Chicano college students who participated in a small group discussion composed of four members: a naive subject who invariably served as group leader, and three confederates representing distinct ethnic groups (Anglo, Black, and Chicano). Behavioral observations revealed several interesting interactions involving group support. High biculturals, in comparison to low biculturals, adopted a more active leader role in nonsupportive than in supportive groups, asking for more opinions and evaluations, and making more clarification statements. Furthermore, while low bicultural externals and high bicultural internals tended to be more interpersonally assertive and to make more clarification statements under supportive conditions, it was low bicultural internals and high bicultural externals who exhibited the most active leader roles in nonsupportive groups. Additional findings revealed that statements made by the Anglo confederate were clarified more often in the supportive condition, while statements made by either the Black or the Chicano confederate were clarified more often in the nonsupportive condition. The results are discussed in relation to previous literature and the need to develop a more responsive social psychology of interethnic dynamics.     

Patterns of perceived similarity cannot be generalized from long to short exposure durations and vice versa

Subjects rated the perceived similarity between patterns and their 180-deg rotational variants. The stimuli, adapted from Halpern, Fishbein, and Warm (1979), were randomly generated dot patterns and line drawings and polygons generated from the dot patterns. Inspection time was varied in a between-subject design. As in the Halpern et al. (1979) study, it was found that the variables of form type (dots, lines, polygons) and axis of rotation (x, y, z) had no effect on perceived similarity in the long exposure conditions. However, when inspection time was limited to 150 msec, both variables had a substantial impact. This finding undermines the frequent practice of selecting stimuli for use in reaction time or other experiments with limited inspection time on the basis of similarity ratings gathered under typical free inspection conditions.     

Cerebral laterality and verbal-performance discrepancies in intelligence

The cerebral laterality of children with various configurations of verbal-performance discrepancies was inferred with an objective measure of lateral preference. Specifically, Verbal and Performance IQ scores of the WISC-R were used to divide 90 learning-disabled children into three equal groups: (a) Verbal significantly higher than Performance, (b) Performance significantly higher than Verbal, and (c) Verbal not significantly different from Performance. Analysis of the scores on the Laterality Preference Schedule showed children in the Verbal > Performance group were significantly more bilateral in their preference patterns than either of the other groups. Data on familial laterality showed this Verbal > Performance group to also have parents who were significantly more mixed in their preference patterns than either the VSIQ < PSIQ or VSIQ = PSIQ groups. The results were interpreted as lending support to the notion of competition antagonism between cortical hemispheres and a possible genetic relationship.     

Values of British political extremists and potential extremists: A discriminant analysis

Studied the value systems of political extremists and potential extremists, comparing them with the value systems of centrist activists and supporters. Samples of political activists from the Labour, Conservative, Communist and National Front parties were obtained, as well as samples of non-active supporters. The non-active supporters were defined as Potential Extremists, if they supported a centrist party as first choice, but either Communist or National Front as second choice. All subjects completed the Rokeach Value Survey. Discriminant analysis showed that the four groups of activists could be clearly distinguished on the bask of their values. However the values of the Potential Extremists did not especially resemble the values of actual National Front or Communist activists. There were value differences between the Potential Extremists and the centrist supporters; nevertheless these two groups tended to be distinguished by very different values from those which distinguished between the activists. The appeal of value symbols for different types of political involvement was discussed.