PSY 350 Lecture Notes - Lecture 24: Statistic, Decision Rule, Test Statistic
Document Summary
We choose between the null and alternative hypotheses based on how likely it is that we would observe our particular sample statistic if the null were true. If it is pretty likely, then the null is probably correct. If it is pretty unlikely, then the alternative is probably correct. We need to make this decision in advance, before we evaluate the data. These decision rules vary but the most common one is that if 5% or fewer of the possible values under the null are more extreme than our sample value. *this should not be confused with cronbach"s alpha. The decision rule we set about the level of probability we will consider. The part of the distribution of sample statistics that is more extreme than (outside) the point in the distribution that corresponds to the alpha. *if the sample statistic we have falls in the critical region, we reject the null hypothesis.
