Question

Suppose I’m trying to determine whether to reject or fail to reject the null hypothesis that the average starting salary of college graduates is at least $45,000. I’ve also taken a survey of size 16 and have found the sample mean to be $40,000 and the sample standard deviation to be 10,000. My alpha value is .05.

1. H₀: H_A: pop. mean < 45,000

2. Write down the probability of Type I Error

3. Write down and compute test statistic

4. Draw Rejection Region:

5. Suppose the p-value is .04

6. State your conclusion about the null hypothesis:

Answer 1

1:

2:

The probability of type I error is

3:

4:

Following graph shows the critical region in blue:

5:

Since p-value is less than 0.05 so we reject the null hypothesis.