Download Chapter 1 Hypothesis Testing

Rejection Region
It is the part of the sample space (critical region) where the null
hypothesis H0 is rejected.
The size of this region, is determined by the probability (α) of the
sample point falling in the critical region when H0 is true. α is also
known as the level of significance, the probability of the value
of the random variable falling in the critical region.
Also it should be noted that the term "Statistical significance"
refers only to the rejection of a null hypothesis at some level α. It
implies only that the observed difference between the sample
statistic and the mean of the sampling distribution did not occur
by chance alone.
Econometrics
Prof. Monica Roman
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