PSYCH 3090 Lecture Notes - Lecture 22: Standard Deviation, Effect Size, Psych
Document Summary
Effect size: for size of an effect when dealing with hypotheses about means, use cohen"s d, an estimate of cohen"s d provided by hedges" g: o g= X hyp s standard error units: expresses mean differences (numerator) in standard deviation units (denominator) not. =0. 328: small = 0. 2, medium = 0. 5, large = 0. 8, these effects are described by cohen"s d, so, this shows a small effect. 35. 5: small = 0. 2, medium = 0. 5, large = 0. 8, shows a medium effect. X hyp g: conventional effect sizes s s. 90: small = 0. 2, medium = 0. 5, large = 0. 8, shows a large effect. Type i and ii errors: when we test statistical hypotheses, we can make two types of errors. When a researcher rejects the null hypothesis (h0) when h0 is true in the. When a researcher fails to reject the null hypothesis (h0) when h0 is false in the population.
