Several years ago, Mischel (1968) pointed out that, on average, only about 10% of the total variance in a particular behavior is systematic variance associated with another variable being studied. Reactions to Mischel's observation were of two varieties.
On one hand, some researchers concluded that the theories and methods of behavioral science must somehow be flawed; surely, if our theories and methods were better we would obtain stronger relationships.
However, others argued that accounting for an average of 10% of the variability in behavior with any single variable is not a bad track record at all. Where do you stand on this issue?
How much of the total variability in a particular phenomenon should we expect to explain with some other variable?