Brian L. Pitcher

The diffusion of collective violence.

Past explanations of violence have characteristically paid more attention to the issues of social conditions and psychocultural stimuli than to the issue of timing. Timing is the focus of this paper in which a differential equation model of the temporal diffusion of violence is developed. This model is derived from behavioral generalizations which indicate that aggression is both instigated and inhibited via direct and vicarious learning. The parameters of the model provide measures of the instigation and inhibition processes that take place throughout an outbreak. Twenty-five data sets representing a wide variety of collective outbreaks of violence are used to test the empirical fit and to evaluate the credibility of the assumptions of the model. The model describes the overtime distribution of incidents quite accurately and the assumptions and implications of the derivation appear to be consistent with the cultural conditions surrounding the outbreaks.

Arms Races: A Test of Two Models

This is an investigation of two models of arms races: Lewis F. Richardsons linear, additive, symmetric model and a curvilinear, asymmetric alternative based on the same interaction paradigm but with empirical equations from psychophysical experiments on perception as premises. Two hypotheses derived from each model are tested using data from seven arms races. In general, the data give stronger support to the curvilinear, asymmetric model which predicts the follower in the arms race will increase its armaments through time as an exponential function of the leaders armaments, and the leader will increase its armaments as a power function of the followers efforts at the previous time period. The conclusions are based on the relative fit of the models to the seven sets of data, parsimony, reasonableness of the parameter estimates as adjudged by their signs and magnitudes, and predictions about the outcomes of the races-war or armed truce.

Older Men's Perceptions of Personal Control: The Effect of Health Status

Data from the Older Male Cohort of the National Longitudinal Surveys are analyzed in this study to investigate antecedents of perceptions of personal control. Particular attention is given to the effects of individual health factors. The findings support the life stress model that assumes that social conditions and environmental changes affect individual perceptions of control via opportunities and resources for carrying out efficacious actions. The analysis suggests, however, that various untested moderating conditions determine the nature and direction of the impact. Future investigations are needed to identify these moderating variables and specify their differential effects.

Collective Learning in Ongoing Political Conflicts

Analyses of political conflict typically concentrate on various structural dimensions and neglect the underlying dynamic processes. In this research, we depart from that practice and take the collective learning process inherent in large-scale and ongoing social conflict as our focus. A mathematical model and its theoretical rationale are developed and evaluated. The model, derived from well-grounded behavioral propositions, assumes that the trend in success/failure rates in this type of conflict is accounted for by the relative learning rates of the parties in conflict. In tests involving several sets of data on conflicts between government and opposition groups in Latin America from 1946 through 1975, the model quite accurately describes the distribution of outcomes.

Stability of perceived personal control for older black and white men.

The recent emergence of the life-span perspective in sociopsychological research has increased attention to the issue of stability versus change in adult personality and behavior. This study uses data on older men from the National Longitudinal Surveys and LISREL statistical procedures to investigate the structural invariance over time, the level stability, and normative stability of perceived personal control within subsamples of blacks and whites.

Patterns of migration propensity for black and white American men. Evidence from a cohort analysis.

This study investigates age, period, and cohort patterns of migration for blacks and whites by applying cohort analysis models to panel data from the young male and older male samples of the National Longitudinal Surveys. The simultaneous inclusion of these four variables represents an important refinement of previous studies that have considered only one or two of them at a time. Principal findings are that age, period, and cohort have independent effects on migration and that the effects differ markedly by race. These findings have significant implications for the development of causal models of migration.

Geographic mobility and locus of control.

Migrants and nonmigrants are often alleged to differ on numerous psychological traits; little empirical analysis, however, has examined this possibility. This study examined the hypothesis that geographic mobility is associated with locus of control, a key dimension of the self-concept. No relationships between these variables were uncovered for a national sample of older white men.

Discriminators of migration propensity among black and white men in the middle and later years.

The objective of this research is to increase our understanding of racial variations in the correlates of migration propensity among men passing through their middle and later years. An analytical model is developed around environmental disamenities, socioeconomic bonds, personal resources, and age. The results suggest the importance of determining the extent to which selected variables differentially discriminate migrants from nonmigrants dependent on race.