Question

Which do you think would be a more serious violation: a Type I or Type II error? And why?

Answer 1

The more serious violation is a Type I error.

In case of a Type I error, we are rejecting the null hypothesis when it is true and in case of a Type II error, we are failing to reject the null hypothesis when it is false. A Type I error is thus termed as false positive and the Type II error is termed as false negative.

With the Type II error, we don't reject the null hypothesis and hence no conclusion is inferred. We just lose a chance to reject the null hypothesis. But in case of a Type I error, we wrongly reject the null hypothesis and state the claim to be true.

This can be a serious error. For example, if we consider a court judge, a Type I error will be to reject the innocence of a culprit, even if he is really innocent. This can be disastrous for the culprit.