How would changing the alpha or the beta for a study affect

How would changing the alpha or the beta for a study affect the results or interpretation of a study? How would a smaller alpha affect the statistical significance of a study result? How about for clinical significance? What is the difference between statistical and clinical significance?

Solution

As the alpha value increases the Beta value for the same study decrease.

The maximum size of the type I error or the risk the resercher is ready to take is called alpha.Generally alpha is fixed before the study is carried out.

if alpha is 0.05 means there is possibility of rejecting the null hypothesis 5 times out of 100 samples although null hypothesis was correct.

hence when we reduce the alpha to 0.01 it means that the possibility of rejecting the null hypothesis is 1 time out of 100 samples although null hypothesis was true.

With this definitely type I error is going to reduce but it is said that type II error (beta) will increse.

Beta means wrong null hypothesis gets accepted.

Hence always there has to be trade off between the two( alpha and beta)

Smaller value of alpha will have greater critical value.

https://freshbiostats.wordpress.com/2014/03/28/statistical-or-clinical-significance-that-is-the-question/

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