Marriage Selection and Age Patterns of Mortality: A Mathematical Investigation

Researchers have acknowledged that the greater longevity of married as compared with unmarried persons may result in part from the mate selection process, namely, more frequent rejection of unhealthy men and women as potential spouses. Can one make inferences about the importance of such selection processes by examining the age pattern of mortality differences by marital status? Several investigators have hypothesized that, if selection were the driving force behind the excess mortality of the single population, the relative mortality ratio (RMR) would decline steadily beyond the upper age at marriage. In this paper, we use simulation models to demonstrate the complexity of the relationship between the marriage selection process and the resulting RMRs. In particular, we show that marriage selection alone can produce a relative mortality ratio which remains large and relatively constant at ages far beyond the marriage spaa.