The dynamics of the population sex ratio

The aim of this dissertation is to examine the relationship between sex differentials in demographic processes and the population sex ratio, in order to provide a basis for the analysis of variations in the population sex ratio across time and space. In Chapter 1, I focus on the effect of mortality on the population sex ratio. For this purpose, I use an alternative cohort-based mortality index, the Period Average Life (PAL). One finding of this chapter is that a period-based analysis is misleading when it comes to examine the effect of mortality change on the population sex ratio, and that conversely the population sex ratio is a poor index of changes in period sex differentials in mortality. In Chapter 2, I propose a multiple decomposition methodology which allows one to quantify the contribution of the sex ratio at birth, sex differentials in mortality, sex differentials in migration and age-structure factors to actual levels and trends in the population sex ratio. The methodology is applied to data from Sweden, France and the United States. In Chapter 3, I add a data-quality component to the analysis of the dynamics of the population sex ratio by examining the debated case of India. Using independent estimates of sex differentials in mortality, I estimate that the Indian population sex ratio peaked between 1981 and 1991, and that recorded deviations from this trend are due to female underenumeration in the 1971 and 1991 censuses. One finding of this chapter is that it took about 25 years for a reversal in period sex differentials in mortality to translate into a reversal in the population sex ratio. Chapter 4 deals with the effect of changes in the sex composition of populations on marriage patterns. Using Romania and Hungary as two empirical examples of countries where large fluctuations in the number of births have produced imbalances in the number of eligible men and women in the marriage market, I show that large deficits have been easily cleared by relatively small changes in ages at marriage and have had little or no impact on celibacy