Page(s) 308-309 10.6. Interrogating Causal Claims with the Four Validities Identify the true and false statements about effect sizes. True Statement(s) The greater the difference between two conditions, the larger the effect size. The correlation coefficient r is always preferred over d for reporting results. Both d and r use the original units of measurement. Effect sizes are relevant to evaluating the causal criterion of covariance. False Statement(s)