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This paper deals with Monte Carlo simulation in case of dependent input random variables. We propose an algorithm to generate refined descriptive samples from dependent random variables for estimation of expectations of functions of output variables using the Iman and Conover algorithm to transform the dependent variables to independent ones. Therefore, such estimates obtained through a chosen mathematical model are compared with those obtained using the simple random sampling method, which proved that the former are the most efficient. Besides, using already published work on independent input variables, we can deduce in case of dependent input random variables, that asymptotically the variance of the RDS estimator is less than that of SRS estimator for any simulation function having finite second moment. [ABSTRACT FROM AUTHOR]

Although the historical impact of racial segregation and ongoing health and economic inequities between older Black and White adults is well documented, little is known about the relationships among race, individual- and neighborhood-resources, and formal volunteering in later life. This study explores this intersection. Individual-level data from 268 respondents aged 55+ were collected in the St. Louis metropolitan area through paper-based mail surveys. Objective neighborhood data were obtained at the zip code level from secondary sources and matched with respondents. Using exploratory factor analysis, we constructed a 14-item environmental scale with 3 neighborhood dimensions (economic, social, and built environment). Older Black adults had lower levels of education; had fewer financial assets; lived in neighborhoods with less economic resources and lower built environment scores; and fewer formally volunteered when compared to older White adults. Individual resources (financial assets, health) and neighborhood resources (social and built environment) were positively associated with formal volunteering among older Black adults. Only individual resources (age, marital status, financial assets, health) were associated with formal volunteering among older White adults. A coherent set of policies that bolsters individual and environmental capacities may increase the rate of volunteerism among older black adults. [ABSTRACT FROM AUTHOR]