The Gamma Distribution as a Mixture of Exponential Distributions

A gamma distribution with arbitrary scale parameter θ and shape parameter r < 1 can be represented as a scale mixture of exponential distributions.     

Bias in transition-specific survival and movement probabilities estimated using capture-recapture data

Transition probabilities can be estimated when capture-recapture data are available from each stratum on every capture occasion using a conditional likelihood approach with the Arnason-Schwarz model. To decompose the fundamental transition probabilities into derived parameters, all movement probabilities must sum to 1 and all individuals in stratum r at time i must have the same probability of survival regardless of which stratum the individual is in at time i + 1. If movement occurs among strata at the end of a sampling interval, survival rates of individuals from the same stratum are likely to be equal. However, if movement occurs between sampling periods and survival rates of individuals from the same stratum are not the same, estimates of stratum survival can be confounded with estimates of movement causing both estimates to be biased. Monte Carlo simulations were made of a three-sample model for a population with two strata using SURVIV. When differences were created in transition-specific survival rates for survival rates from the same stratum, relative bias was <2% in estimates of stratum survival and capture rates but relative bias in movement rates was much higher and varied. The magnitude of the relative bias in the movement estimate depended on the relative difference between the transition-specific survival rates and the corresponding stratum survival rate. The direction of the bias in movement rate estimates was opposite to the direction of this difference. Increases in relative bias due to increasing heterogeneity in probabilities of survival, movement and capture were small except when survival and capture probabilities were positively correlated within individuals.     

The Sale of Two Cities: A Semiotic Comparison of Disneyland with Marriott's Great America

Much is revealed through the contrast of two related but divergent forms. In this essay, Elizabeth Mechlingand Jay Mechlingcontrast Disneyland with a later but more loosely themed park, Marriott's Great America in Santa Clara, California. Using the perspectives and methods of semiotics in Louis Marin's Marxist reading, this essay asks, “What are the stories that Disneyland and Marriott's Great America tell?…the ways in which popular culture both teaches and evokes stories that ‘think themselves’ in our minds.” These two parks, though allied in the theme format and rooted in a common bourgeois capitalist culture, are found to promote very different attitudes and values.     

Counseling for Continued Career Development After Retirement: An Application of the Theory of Work Adjustment

The theory of work adjustment (TWA; R. V. Dawis & L. H. Lofquist, 1984; L. H. Lofquist & R. V. Dawis, 1969, 1991) is useful in addressing the career counseling needs of retirees who want to continue working but who need to explore their career choices before settling on a new occupation or job. This article examines some of the challenges that midlife and older adults face as they plan postretirement careers. Information about TWA and a case example are provided to assist counselors in understanding how TWA can be applied to retirement career counseling.     

Visualizing Structure: Reading Surfaces of Social Life

This paper reports on the use of aerial photographs to study the social structure of a dairy farm neighborhood in St. Lawrence County, New York. The paper compares information from aerial photographs of farmsteads and farm work to data gathered in a sociological survey. I examine how the visual data compares to other sociological information; how photographs, in this research, amplify, supplement, or contextualize nonvisual data.     

DIRECT AND INDIRECT EFFECTS OF RELIGION ON BIRTH TIMING:

The effect of being Catholic on first-birth timing (hereafter, birth timing) varies according to how the dependent variable is measured. When birth timing is measured as age at first birth, Catholics' is slower than non-Catholics'; measured as duration from marriage, Catholics' is more rapid. Structural equation models for discrete data showing these findings explain that Catholics marry later than non-Catholics. The direct effect of being Catholic is to speed birth timing, while the larger, indirect effect (through marital status) is to slow it.     

Unintended consequences of Immigration Reform: Discrimination and hispanic employment

The record-keeping requirements of the Immigration Reform and Control Act(IRCA), and fines for illegal employment, may induce employers to discriminate against foreign-appearing workers. The General Accounting Office (GAO) reported widespread IRCA-related discrimination but did not link reported discriminatory practices to discriminatory employment behavior. We analyze the GAO’s random survey and, controlling for selectivity effects, demonstrate that employers who report discriminatory practices actually employ fewer Hispanics. Although the measured reduction of Hispanic employment due to IRCA is fairly small, this finding parallels research alerting us to adverse consequences of a law that so far has achieved few of its intended effects.     

Strength in Process: Using Concept Mapping to Inform Community Coalition Development

This study reports on the use of Concept Mapping to delineate a conceptual framework germane to the planning and initial formation of tri-county rural diabetes coalition in a southeast US community. The focus of the tricounty coalition is to reduce diabetes-related inequalities in vulnerable populations. After a review of pertinent literature on community coalitions, this article explicates Concept Mapping processes utilized to plan and organize the formation of a coalition, offers analyses of the results, and discusses implications for current and future practices pertaining to community coalition work.