This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Research Institute gathers three institutes that measure belief by numbers, though in two entirely different senses of the word.
The California Institute of Numerical Research, founded in 1931 to carry forward and systematise the numerology L. Dow Balliett had taught, is the institutional source of what is now usually sold as the Pythagorean numerology system. Under Juno Jordan's decades of leadership its publications fixed the letter to number table, the treatment of master numbers and the calculation of the life path that most modern English language numerology still follows. It was a private teaching and publishing body rather than an academic one, and its results were never tested by anyone outside it.
Pew Research Center and Barna Group measure belief the opposite way, by counting believers rather than assigning them numbers. Pew, a nonpartisan, nonadvocacy organization established in 2004, produces some of the most widely cited survey research on global religion, including the Religious Landscape Study and the Global Religious Landscape population estimates this atlas draws on repeatedly. Barna Group, founded by George and Nancy Barna in 1984, has conducted more than two million interviews since, focused particularly on the beliefs, practices and generational trends of American evangelical Christians, and is the other of the two most widely cited sources for quantitative American religious data.
What separates the three is method rather than subject: one institute built a private numerological system never tested outside itself, and two built public survey instruments whose findings other researchers can check.