Compare methods

	Religious Vitality Index	Congregational Network Analysis
Field	Sociology Of Religion	Sociology Of Religion
Family	Process / pipeline	Process / pipeline
Year of origin	1994	2018
Originator	Laurence R. Iannaccone	Sean F. Everton
Type	Index/model of religious group strength via strictness	Social network analysis applied to religious communities
Seminal source	Iannaccone, L. R. (1994). Why Strict Churches Are Strong. American Journal of Sociology, 99(5), 1180-1211.	Everton, S. F. (2018). Networks and Religion: Ties That Bind, Loose, Build-Up and Tear Down. Cambridge: Cambridge University Press. ISBN: 9781108404075
Aliases	Church Strength Index, Strictness-Vitality Measure, Religious Group Strength Model, Free-Rider Vitality Index	Religious Network Analysis, Faith Community Network Analysis, Congregation Social Network Analysis, Networks-and-Religion Analysis
Related	3	3
Summary	The religious vitality index operationalizes Laurence Iannaccone's celebrated argument, in his 1994 American Journal of Sociology article 'Why Strict Churches Are Strong,' that demanding religious groups are often the most vital. The seeming paradox dissolves once religion is viewed as a collective good vulnerable to free-riding: if members can enjoy the fellowship, enthusiasm, and mutual support of a congregation while contributing little, average commitment erodes and the group weakens. Strictness - costly, distinctive demands such as dress codes, time obligations, and behavioral prohibitions - works as a screening device that drives out the half-hearted and raises the average commitment of those who remain. The vitality index therefore models a group's strength as a function of its strictness, its members' participation, and its capacity to retain and mobilize committed adherents.	Congregational network analysis applies social network analysis to religious communities, treating congregations and their members as nodes connected by ties of friendship, kinship, recruitment, and shared participation. Rather than studying individuals in isolation, it asks how the structure of relationships within and between faith communities shapes who joins, who stays, how commitment spreads, and how movements grow or fracture. Sean Everton's Networks and Religion (2018) organizes the field around the idea that ties bind people into communities, loose them from old commitments, build up movements, and tear them down, showing across recruitment, conversion, and decline that relational structure is often a better predictor of religious outcomes than individual attributes alone.