Stat & Prob M5

If the level of significance decreased from 0.1 to 0.05, then the boundaries for the critical region move farther away from the center of the distribution.

• true

• false

• both A and B

• cannot be determined

For a one-tailed test with a sample of 15, the null hypothesis will not be rejected at 5% level of significance if the test statistics is:

• 𝑡≤−1.761

• 𝑡≤−1.753

• 𝑡≤−1.703

• 𝑡≤−1.697

Which of the following defines the area encompassed by the values not included in the non-rejection region or also the area of the tails of the distribution?

• critical value

• rejection region

• level of significance

• population variance

In a left-tailed test with 𝛼=0.01, the critical value of z is:

• -2.576

• -2.330

• -1.960

• -1.645

For a two-tailed test with variance unknown, n= 16, and 𝛼=0.05, what is the critical value?

• ±2.092

• ±2.134

• ±2.145

• ±2.125

What is the critical value if the population variance is known, 𝑎=0.025, and it is a two-tailed test?

• 𝑧=±1.28

• 𝑧=±1.645

• 𝑧=±1.96

• 𝑧=±2.33

Given a left-tailed test, population standard deviation is unknown, 𝑛=27, 𝛼=0.01, what is the critical value?

• 𝑡=−2.528

• 𝑡=−2.479

• 𝑡=−1.706

• 𝑡=2.479

What is the rejection region of the given normal curve at the right?

• 𝑧≥1.28

• 𝑧≥1.645

• 𝑧≥1.96

• 𝑧≤2.33

Based on the graph, which of the following is TRUE?

• This is a two-tailed test.

• This is a right-tailed test.

• Level of significance is 0.025.

• The rejection region is 𝑡≤ -1.725.

In a right-tailed test, the rejection lies in the ________ tail of distribution.

• up

• left

• right

• down