One Hundred Years of Social Psychology Quantitatively Described

TLDR

The article aggregates over 25,000 social psychology studies involving 8 million participants, compiling 322 meta‑analyses and effect‑size summaries to provide a quantitative overview of the field. The compilation shows that social psychological effects average r≈0.21 with a typical inter‑study standard deviation of 0.15, highlighting the magnitude and variability of these effects.

Abstract

This article compiles results from a century of social psychological research, more than 25,000 studies of 8 million people. A large number of social psychological conclusions are listed alongside meta-analytic information about the magnitude and variability of the corresponding effects. References to 322 meta-analyses of social psychological phenomena are presented, as well as statistical effect-size summaries. Analyses reveal that social psychological effects typically yield a value of r equal to.21 and that, in the typical research literature, effects vary from study to study in ways that produce a standard deviation in r of.15. Uses, limitations, and implications of this large-scale compilation are noted.