Sample size and the detection of correlation--a signal detection account: comment on Kareev (2000) and Juslin and Olsson (2005).
Simulations examined the hypothesis that small samples can provide better grounds for inferring the existence of a population correlation, p, than can large samples. Samples of 5, 7, 10, 15, or 30 data pairs were drawn either from a population with p=0 or from one with p>0. When decision accuracy was assessed independently for each level of the decision criterion, there was a criterion-specific small-sample advantage. For liberal criteria, accuracy was greater for large than for small samples, but for conservative criteria, the opposite result occurred. There was no small-sample advantage when accuracy was measured as the area under a receiver operating characteristic curve or as the posterior probability of a hit. The results show that small-sample advantages can occur, but under limited conditions.
Anderson
Richard B
RB
Department of Psychology, Bowling Green State University, Bowling Green, OH 43403, USA. randers@bgnet.bgsu.edu
Doherty
Michael E
ME
Berg
Neil D
ND
Friedrich
Jeff C
JC
D006801:Humans; D008960:Models, Psychological; D011584:Psychology / Q000379:methods / Q000706:statistics & numerical data; D012372:ROC Curve; D018401:Sample Size; D017603:Signal Detection, Psychological