PSYC 2360 Lecture Notes - Lecture 5: Observational Error, Dependent And Independent Variables, Effect Size
23 Mar 2016
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Document Summary
Research indings are based on samples drawn from populaions. Inferenial staisics allow us to infer what the populaion is like, based on sample data. The distribuion of all the possible values of a staisic (ex. Correct guesses, mean: sampling distribuion of the mean. Plot the means distribuion of sample means. Assumes observed data do not difer from what would be expected on the basis of chance: mean of the experimental group equals mean of control group, correlaion between 2 variables is r=0. We want to reject the null hypothesis. Before we reject the null hypothesis, the observed data must deviate substanialy from what would be expected under the sampling distribuion. The standard that the observed data must meet is known as the signiicance level or alpha ( =. 05: we may reject the null hypothesis only if the observed data are so unusual that they would have occurred by chance at most 5% of the ime, alpha.
