PSYC 300B Chapter Notes - Chapter 2: Null Hypothesis, Sampling Distribution, Time Point

• School: University of Victoria
• Department: Psychology
• Course: PSYC 300B
• Professor: David Medler

Document Summary

Also called repeated measures, dependent measures, within-groups, paired-samples. (+) requires fewer participants, time, & resources. (+) fewer external in uences on behaviour (confounding variables) (+) has a baseline score for participants & therefore just measures the change between measures. (-) carry-over or practice effects due to repeated testing. (-) loss of participants through attrition: if you lose a participant at the second time point, you must discard their data from the rst time point. Critical value is determined from the t-table of critical values, based on values for df & a. Use the test ratio for related-samples t-test . Assumes no difference & that there is no change between the 2 trials or conditions: variability d is unknown & estimated by sd from sample, shape usually unknown, but assumed to be normal distribution. If sample size n 25, shape of the population is not relevant. Represents the mean of the mean difference scores.