BNAD 276 Lecture Notes - Lecture 11: Null Hypothesis, Statistical Hypothesis Testing, Sampling Distribution

• School: University of Arizona
• Department: Business Administration
• Course: BNAD 276
• Professor: Suzanne Delaney

Document Summary

Rejecting the null - the result is statistically significant if: the observed statistic is larger than the critical statistic. If we want to reject the null, we want our z to be big: the p value is less than 0. 05 (which is our alpha). If we want to reject the null, we want our p to be small! Setting our decision threshold: level of significance is called alpha. If the observed z falls beyond the critical z in the distribution then it is so rare, we conclude it must be from other distribution. One vs two tail test of significance: different critical scores but same alpha level, from two-tailed to one-tailed: critical z becomes smaller. One tail test requires: a unidirectional prediction (predict which group will have larger mean, that the results actually be in the predicted direction (predicted mean is larger) In a one-tailed test the region of rejection refers to results in the predicted direction.