John rejected his null hypothesis in a twotailed test for a

John rejected his null hypothesis in a two-tailed test for a mean at = .05 because his critical t value was 2.000 and his calculated t value (the test statistic) was 2.345. We can be sure that...

a. John did not commit Type I error.

b. John did not commit Type II error.

c. John committed neither Type I nor Type II error.

d. John committed both Type I and Type II error.

Solution

We can commit a type I error if and only if we reject the null hypothesis.

We can commit a type II error if and only if we fail to reject the null hypothesis.

here, he rejected the null hypothesis. Hence,

OPTION B: John did not commit a Type II error. [ANSWER, B]