Short term individual and small group behavior in artificial conditions can be somewhat reliably measured. How well and to what situations these genralize to is a harder question.

Larger groups and timescales are (in practice) outside the domain of science (in the most rigorous form) and must be studied with other methods and epistemological criteria. This also leads to major abuse of statistics as the inference has to be done with unrealistic assumptions and unwieldly models.

The "brand" of science is so strong that many fields, especially economics, want to appropriate it even though they don't and can't do science in the strict definition.