Undecidability,incompleteness and Arnol'd problems

We present some recent technical results of us on the incompleteness of classical analysis and then discuss our work on the Arnol'd decision problems for the stability of fixed points of dynamical systems.Partially supported by FAPESP and CNP_q (Brazil, Philosophy Section).     

Note critiche

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Critical notices

     

Influence of life event stress on physical illness: substantive effects or methodological flaws?

This study tests the hypothesis that the reported relationship between life event stress and physical illness is primarily a function of criterion and other content contamination in the stress measure. In particular, conventional life event measures include events related to physical health, which overlap with the criterion; events related to neuroticism, which influences the criterion; and events that are vague or subjective and could be affected by individual differences in psychological distress, response sets, and retrospective bias. In this study 386 adult males and females completed standard measures of life events and physical illness. Illness was significantly related to event subscales containing, respectively, health-related events, neuroticism-related events, and subjective events, but not to an "uncontaminated" event subscale. These results support the hypothesis of contamination and suggest that alternative approaches to the conceptualization and measurement of stress may need to be developed.     

Declines in divergent thinking with age: cross-sectional, longitudinal, and cross-sequential analyses

Six measures of divergent thinking were administered to 825 men ranging in age from 17 to 101 over the period from 1959 to 1972; repeat administrations were given to a subset of 278 men after a 6-year interval. Cross-sectional analyses showed curvilinear trends, with an increase in scores for men under 40 and a decline thereafter. Repeated measures analyses on subjects initially aged 33 to 74 generally replicated this finding, whereas cross-sequential analyses suggested a decline for all cohorts tested at a later time. Additional analyses suggested that not all of the decline could be attributed to reduced speed of response production. These longitudinal findings confirm earlier cross-sectional reports of decline in divergent thinking abilities with age.     

Size scaling in two-dimensional pictorial arrays

The study examined effects of instructional sets (objective, phenomenal, projective, and retinal) on the judged sizes of blocks placed at various “distances” in a pictorial array. Magnitude estimations of size were consistent with previous studies of size constancy in three-dimensional arrays. Chronometric analyses indicated that reaction time increased with distal size, but was not affected by perceived distance. The results suggested that size was scaled relative to a perceptual unit. Instructions affected the nature of the scale unit (proximal vs. distal), but not the scaling process itself.     

Validation of the five-factor model of personality across instruments and observers

Two data sources--self-reports and peer ratings--and two instruments--adjective factors and questionnaire scales--were used to assess the five-factor model of personality. As in a previous study of self-reports (McCrae & Costa, 1985b), adjective factors of neuroticism, extraversion, openness to experience, agreeableness-antagonism, and conscientiousness-undirectedness were identified in an analysis of 738 peer ratings of 275 adult subjects. Intraclass correlations among raters, ranging from .30 to .65, and correlations between mean peer ratings and self-reports, from .25 to .62, showed substantial cross-observer agreement on all five adjective factors. Similar results were seen in analyses of scales from the NEO Personality Inventory. Items from the adjective factors were used as guides in a discussion of the nature of the five factors. These data reinforce recent appeals for the adoption of the five-factor model in personality research and assessment.