PSYC 301 Lecture Notes - Lecture 12: Type I And Type Ii Errors, Null Hypothesis, Sampling Distribution
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A small sample standard deviation a) b) c) d) The standard deviation of a sampling distribution of the mean is called the standard error of the mean. P(retain h0 | h0 is true) = 1- . P(retain h0 | h0 is false(cid:895) = . P(reject h0 | h0 is true(cid:895) = . P(reject h0 | h0 is false) = 1- . The pro(cid:271)a(cid:271)ility of a type i error (cid:894) (cid:895), the a priori level of significance and the criterion for rejecting. If we are willing to in(cid:272)rease then de(cid:272)reases and power in(cid:272)reases. 1-tailed tests are more powerful than 2-tailed tests. Nonetheless, use a 2-tailed test unless you are not at all interested in mean differences that may occur in a particular direction. In this case, you"ve already analyzed your data. Typically, there"s an effect of interest that was not statistically significant. You ask yourself if the failure to reject the null was not due to a lack of population group.
