PSYC 300 Chapter 8: notes 8
9 Mar 2017
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Document Summary
Research methods for the behavioral sciences chapter 8. Probability and inferential statistics: impossible to know if observed data caused by random error. Binomial distribution - sampling distribution for events that have 2 equally likely possibilities. Sampling distribution gets narrower as sample size (n) increases: null hypothesis (h0) - assumption that observed data reflects only what would be expected under the sampling distribution. Specifies least interesting possible outcome, so researcher"s goal is to reject it: testing for statistical significance. Setting alpha ( ) - observed data must substantially deviate from what"s expected under sampling distribution before it can be ok to reject h0. Each statistic has an associated probability value (p-value) Likelihood of an observed statistic occurring on the basis of sampling distribution. Alpha ( ) sets standard for how extreme data must be in order to reject h0: p-value < 0. 05 ( ): reject h0, results statistically significant, p-value < 0. 05: fail to reject h0, results statistically.
