Undercutting and the Ramsey test for conditionals

There is an important class of conditionals whose assertibility conditions are not given by the Ramsey test but by an inductive extension of that test. Such inductive Ramsey conditionals fail to satisfy some of the core properties of plain conditionals. Associated principles of nonmonotonic inference should not be assumed to hold generally if interpretations in terms of induction or appeals to total evidence are not to be ruled out.     

The origins and function of the reference point in risky group decision making the case of the Cuban missile crisis

This case study explores reference level effects on group decision making during the Cuban missile crisis of 1962. The group is composed of American President John F. Kennedy and his advisers. The results are consistent with much experimental evidence showing that reference levels play an important role in determining preferences. The results also extend the notion of reference-dependent risky choice to the group level, where the group consists of seasoned experts who each have a different role to play within the group and who are dealing with an issue of great importance.     

The Reluctance to Expose Dangerous Lies1

Three studies examined a hypothesized inhibition against exposing a lie. In Experiment 1, 21 men and 27 women were placed in conditions in which their nonexposure of another's lie resulted either in the risk of an experimenter's data being contaminated (impersonal consequence), or in the risk of the subject contracting pinkeye (personal consequence). Each person was given the opportunity to expose the lie, first in a group setting, and later in a private setting. Eighty-three percent of the subjects in the impersonal condition and 77% of the subjects in the personal condition failed to expose the lie. Experiment 2 explored the phenomenon further by assessing whether subjects not in the presence of individuals other than the liar would be more likely to confront the lie. As in Experiment 1, it was found that most subjects did not reveal the lie, regardless of consequence condition of setting. In Experiment 3, it was anticipated that objective self-awareness would interact with consequence information to produce more exposing behavior in the personal-consequence condition, but not in the impersonal condition. Results generally confirmed the hypothesis; a significant interaction of Consequence x Self-Awareness Condition was found.     

Generalization of parent-training results

Two experiments were conducted to assess the generalized effects of several different parent/teacher training programs. In Experiment I it was found that a brief demonstration of how to teach an autistic child new behaviors was sufficient to teach parents how to teach those children those behaviors. However, generalization to new child-target behaviors did not take place. Another parent training program, which did not demonstrate how to teach any one specific child behavior, but was based on teaching the use of general behavior-modification procedures, was effective in teaching the parents how to teach new child-target behaviors. Experiment II then provided analyses of the individual effects of several components of the generalized training program. The results showed that videotape illustrations of the procedures, without the presence of a master teacher, were sufficient to teach the adults. However, sub-parts of the videotapes produced highly specific training results, with each component changing corresponding areas of the adults' behaviors. Viewing of the entire package was necessary before the adults were able to improve the autistic children's behaviors. The study as a whole suggests the importance of obtaining multiple measures of the effects of parent and teacher training programs, including measures of acquisition and generalization of both adult and child behaviors.     

Canonical versus factor analytic perspectives on the structure of associations between the MMPI and the Buss-Durkee Hostility Inventory

A canonical correlational analysis of MMPI profiles versus Buss-Durkee hostility and aggression scales was conducted, resulting in the identification of a general hostility-aggression-maladjustment dimension and three relatively specific aggression-personality relationships. These findings were contrasted with those obtained from a factor analysis of the combination of both sets of scores. Though often used in previous studies of associations between the Buss-Durkee Hostility Inventory and other measures, factor analysis was seen to be less than optimally suited to such a purpose. It was concluded that canonical correlation is preferable to factor analysis when seeking to clarify the multivariate structure of relationships between two sets of variables.     

I. Genotype-environment interaction in the schizophrenia spectrum: genetic liability and global family ratings in the Finnish Adoption Study

In the Finnish Adoption Study, a national sample of adoptees with high versus low genetic liability for schizophrenia spectrum disorders was indexed by DSM-III-R diagnoses of their biological, adopting-away mothers. The rearing-family environments of the adoptees were independently evaluated from global ratings of directly observed adoptive family relationships. The interaction of high genetic liability and dysfunction of the rearing families predicted highly significantly to schizophrenia spectrum disorder of the adoptees at 21-year follow-up. Either low genetic liability or healthy rearing protected against a spectrum outcomes for the adoptees. Initial adoptive parent diagnosis, as a proxy for rearing family dysfunction, predicted to adoptee outcome only as a trend.     

The perceived strength of illusory contours.

Illusory contours are not well understood, partially because a lack of physical substance complicates their specification via physical standards. One solution is to gauge illusory contours with respect to luminance-defined contours, which are easily quantified physically. Accordingly, we chose a metric (perceived contrast) that expresses illusory contour strength in terms of the physical contrast of luminance-defined contours. Using this metric, adult observers adjusted the contrast of a luminance-defined contour until it matched the perceived contrast of an illusory contour. Illusory contour length, inducer size, and inducer contrast all influenced illusory contour strength. The results are adequately explained via low-level visual processes. It appears that matching paradigms can be beneficial in quantitative studies of illusory contours.