Tests and confidence intervals The P-value for a two-sided test of the null hypothesis H0:μ=10is0.06

a. Does the 95% confidence interval for μ include 10? Why or why not?

b. Does the 90% confidence interval for μ include 10? Why or why not?

Short Answer

Expert verified

Part (a) Yes.

Part (b) No.

Step by step solution

01

Part (a) Step 1: Given information

H0:μ=10H1:μ10P=0.06
02

Part (a) Step 2: Explanation

If the P-value is lesser than the significance level then the null hypothesis is rejected.

P=0.06>0.05=5%FailtorejectH0

A significance test at the 5% significance level is associated with a 95 percent confidence interval.

The 95 percent confidence interval comprises the value given in the null hypothesis 10 because the null hypothesis failed to reject at the 5% significance level.

03

Part (b) Step 1: Explanation

The null hypothesis is rejected if theP-value is less than the significance level.

P=0.06<0.10=10%RejectH0

A significance test at the 10% significance level is associated with a 90 percent confidence interval.

The 95 percent confidence interval does not have the value specified in the null hypothesis 10 since the null hypothesis was rejected at the 10% significance level.

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