UC Davis

Three significant demographic phenomena occurred in the Western world in the 20th century. Firstly, the fertility rates skyrocketed after 1945, giving birth to the Baby Boomer's birth cohorts. Secondly, social surveys have shown that the Baby Boomers, on average, reported a lower level of subjective well-being and self-rated health than other birth cohorts. This phenomenon is puzzling demographers because baby boomers in these countries were economically and politically better off than other generations, especially in countries like the United States and the United Kingdom. The United States –Baby Boomer cohorts are some of the most overcrowded, unhappy, lonely, and sick cohorts in the modern U.S. The third phenomenon is that baby boomers are the loneliest birth cohorts born in the 20th century, but they are a part of a generation that is supposed to be crowded with siblings, friends, and peers. This dissertation will contribute to studying the cohort effect on subjective well-being. It will elaborate on the definition and characteristics of birth cohorts. Utilizing the Hierarchical Age Period Cohort modeling and comparative methods, this study will analyze the “baby boomer” effect in the U.S. and conduct a multi-countries comparison analysis in the U.S., U.K. and other non-Western countries. By analyzing these puzzling cases globally, this dissertation aims to 1) illustrate demographic patterns – viz. the age, period, cohort, and cohort size effect on health and happiness, 2) contribute to our understanding of the mechanisms of how cohort size affects subjective well-being, 3) to analyze other factors that explain cohort inequalities in subjective wellbeing, 4) and to unveil the macro structural forces that contextualize the cohort and cohort size effects. I also discuss public health implications and plan for future research.