Question

1. Assume we are conducting a hypothesis test at the 5% significance level.

   1. Find the p-value for a left-tailed test if z0= -1.92. Is there enough evidence to reject the

      null hypothesis?

   2. Find the p-value for a right-tailed test if z0= 2.53. Is there enough evidence to reject the

      null hypothesis?

   3. Find the p-value for a two-tailed test if z0= -2.91. Is there enough evidence to reject the

      null hypothesis?

   4. Find the p-value for a two-tailed test if z0= 2.88. Is there enough evidence to reject the

      null hypothesis?

Answer 1

Answer)

A)

From z table, P(z<-1.92) = 0.0274

As the obtained p-value is less than 5% (0.05)

We reject the null hypothesis Ho

There is enough evidence to reject the null hypothesis

B)

P(z>2.53) = 0.0057

As p-value < 0.05

There is enough evidence to reject the null hypothesis

C)

P(z<-2.91) = 0.0018

As the test is two tailed

P-value = 2*0.0018 = 0.0036

As 0.0036 < 0.05

There is enough evidence to reject the null hypothesis.

D)

From z table, P(z>2.88) = 0.002

As the test is two tailed

P-value = 2*0.002 = 0.004

As the obtained p-value is less than 0.05

We reject the null hypothesis