Vanguards, Laggards, and Isolates: Outliers and Demographic Research

In what way can demographic research, a field of study that aims to analyze population change, benefit from studying outlying groups, countries, or events? Our analytic work suggests that three types of outliers might emerge in demographic transitions: 1) Vanguards – the initiators of the transition; 2) Laggards – late adopters of the innovative behavior; and 3) Isolates – those who never joined the transition. We discuss the advantages of analyzing outliers, the barriers that impede such research, and the implications of failing to identify them. Identifying vanguard groups might help demographers locate the onset of a demographic transition, make more accurate projections, and better anticipate the potential trajectory that other groups will experience. Studying laggard populations allows exploring the mechanisms that facilitate or impede the adoption of a new behavior. Isolates can help demographers learn about the essentials of demographic processes, before they were affected by other changes.