Question 1

Suppose the alternative hypothesis in a hypothesis test is: "the population mean is less than 60." If the sample size is 50 and alpha =.05, the critical value of z is ___.

Accepted Answer

A)  1.645 
B)  -1.645 
C)  1.96 
D)  -1.96 
E)  2.05

Question 2

A researcher is testing a hypothesis of a single mean. The critical z value for $\alpha$ =.05 and a two-tailed test is ±1.96. The test statistic from sample data is -1.85. The decision made by the researcher based on this information is to ___ the null hypothesis.

Accepted Answer

A)  reject 
B)  not reject 
C)  redefine 
D)  change the alternate hypothesis into 
E)  restate the null hypothesis

Question 3

When a true null hypothesis is rejected, the researcher has made a Type I error.

Accepted Answer

A) True 
 B)False

Question 4

A company believes that it controls more than 30% of the total market share for one of its products. To prove this belief, a random sample of 144 purchases of this product is contacted. It is found that 50 of the 144 purchased this company's brand of the product. If a researcher wants to conduct a statistical test for this problem, the test would be ___.

Accepted Answer

A)  a one-tailed test 
B)  a two-tailed test 
C)  an alpha test 
D)  a finite population test 
E)  a finite sample test

Question 5

When a $\textbf{      false    }$  null hypothesis is rejected, the researcher has made a Type II error.

Accepted Answer

A) True 
 B)False

Question 6

Jennifer Cantu, VP of Customer Services at Tri-City Auto Insurance Inc., monitors the claims processing time of the claims division. Her standard includes "a mean processing time of 5 days or less." Each week, her staff checks for compliance by analyzing a random sample of 60 claims. Jennifer's null hypothesis is ___.

Accepted Answer

A)  $\mu$ > 5 
B)  $\sigma$ > 5 
C)  n = 60 
D)  $\mu$ < 5 
E)  $\mu$ = 5

Question 7

An article in the Edmonton Journal about driving practices in Strathcona County, claimed that 48% of drivers did $\textbf{      not   }$  stop at stop-sign intersections on county roads. A follow-up study of 800 drivers on the county roads showed that 360 did $\textbf{    not     }$  stop at stop-sign intersections. At $\alpha$ = 0.05 
, is there evidence to suugest that the proportion of drivers $\textbf{   not      }$  stopping at stop-sign intersections has changed using the p value approach.

Accepted Answer

The answer of An article in the Edmonton Journal about...

Question 8

If the p value for a hypothesis test is 0.0271, which would be a correct decision?

Accepted Answer

A)  Do not reject the null hypothesis when alpha is 0.10. 
B)  Do not reject the null hypothesis when alpha is 0.05. 
C)  Reject the null hypothesis when alpha is 0.025. 
D)  Reject the null hypothesis when alpha is 0.10. 
E)  none of the above

Question 9

In performing a hypothesis test where the null hypothesis is that the population mean is 6.9 against the alternative hypothesis that the population mean is $\textbf{   not      }$  equal to 6.9, a random sample of 16 items is selected. The sample mean is 7.1 and the sample standard deviation is 2.4. It can be assumed that the population is normally distributed. The level of significance is selected as 0.05. The critical t value for this problem is ___.

Accepted Answer

A)  1.753 
B)  2.947 
C)  2.120 
D)  2.131 
E)  2.311

Question 10

Suppose you are testing the null hypothesis that a population mean is less than or equal to 80, against the alternative hypothesis that the population mean is greater than 80. If the sample size is 49 and alpha =.10, the critical value of z is ___.

Accepted Answer

A)  1.645 
B)  -1.645 
C)  1.28 
D)  -1.28 
E)  2.33

Question 11

Ophelia O'Brien, VP of Consumer Credit of Credit First Banks (CFB), monitors the default rate on personal loans at the CFB member banks. One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans. Last Friday's sample contained 30 defaulted loans. Using
$\alpha$ = 0.10, the critical z value is ___.

Accepted Answer

A)  1.645 
B)  -1.645 
C)  1.28 
D)  -1.28 
E)  2.28

Question 12

The null hypothesis makes claim about a

Accepted Answer

A)  population parameter. 
B)  sample statistics. 
C)  Type I error. 
D)  Type II error. 
E)  sample mean.

Question 13

Hypotheses are tentative explanations of a principle operating in nature.

Accepted Answer

A) True 
 B)False

Question 14

In a two-tailed hypothesis about a population mean with a sample size of 100 and α = 0.05, the rejection region would be ___.

Accepted Answer

A)  z > 1.64 
B)  z > 1.96 
C)  z  1.96 
D)  z  1.64 
E)  z  2.33

Question 15

Consider the following null and alternative hypotheses: 
H0: π $\le$ 0.16
Ha: π > 0.16
These hypotheses ___.

Accepted Answer

A)  indicate a one-tailed test with a rejection area in the right tail 
B)  indicate a one-tailed test with a rejection area in the left tail 
C)  indicate a two-tailed test 
D)  are established incorrectly 
E)  are not mutually exclusive

Question 16

In performing a hypothesis test where the null hypothesis is that the population mean is 4.8 against the alternative hypothesis that the population mean is $\textbf{        not }$  equal to 4.8, a random sample of 25 items is selected. The sample mean is 4.1 and the sample standard deviation is 1.4. It can be assumed that the population is normally distributed. The degrees of freedom associated with this are ___.

Accepted Answer

A)  25 
B)  24 
C)  26 
D)  2 
E)  1

Question 17

Consider the following null and alternative hypotheses: 
Ho: µ $\ge$ 67
Ha: µ < 67
These hypotheses ___.

Accepted Answer

A)  indicate a one-tailed test with a rejection area in the right tail 
B)  indicate a one-tailed test with a rejection area in the left tail 
C)  indicate a two-tailed test 
D)  are established incorrectly 
E)  are not mutually exclusive

Question 18

Ophelia O'Brien, VP of Consumer Credit of Credit First Banks (CFB), monitors the default rate on personal loans at the CFB member banks. One of her standards is "no more than 5% of personal loans should be in default." On each Friday, the default rate is calculated for a sample of 500 personal loans. Last Friday's sample contained 30 defaulted loans. Using $\alpha$ = 0.10, the test statistic is ___.

Accepted Answer

A)  1.03 
B)  -1.03 
C)  0.046 
D)  -0.046 
E)  1.33

Question 19

The diameter of 3.5 centimetre discs is normally distributed. Periodically, quality control inspectors at Winnipeg Discs randomly select a sample of 16 discs. If the mean diameter of the discs is too large or too small the disc punch is shut down for adjustment; otherwise, the punching process continues. The last sample showed a mean and standard deviation of 3.49 and 0.08 centimetres, respectively. Using $\alpha$= 0.05, the critical t values are ___.

Accepted Answer

A)  -2.120 and 2.120 
B)  -2.131 and 2.131 
C)  -1.753 and 1.753 
D)  -1.746 and 1.746 
E)  -2.567 and 2.567

Question 20

A researcher is testing a hypothesis of a single mean. The critical z value for $\alpha$=.05 and a two-tailed test is ±1.96. The observed z value from sample data is -2.11. The decision made by the researcher based on this information is to ___ the null hypothesis.

Accepted Answer

A)  reject 
B)  not reject 
C)  redefine 
D)  change the alternate hypothesis into 
E)  restate the null hypothesis

Exam 11: Hypothesis Testing for Single Populations

Suppose the alternative hypothesis in a hypothesis test is: "the population mean is less than 60." If the sample size is 50 and alpha =.05, the critical value of z is ___.

A researcher is testing a hypothesis of a single mean. The critical z value for $\alpha$ =.05 and a two-tailed test is ±1.96. The test statistic from sample data is -1.85. The decision made by the researcher based on this information is to ___ the null hypothesis.

When a true null hypothesis is rejected, the researcher has made a Type I error.

When a $\textbf{ false }$ null hypothesis is rejected, the researcher has made a Type II error.

If the p value for a hypothesis test is 0.0271, which would be a correct decision?

Suppose you are testing the null hypothesis that a population mean is less than or equal to 80, against the alternative hypothesis that the population mean is greater than 80. If the sample size is 49 and alpha =.10, the critical value of z is ___.

The null hypothesis makes claim about a

Hypotheses are tentative explanations of a principle operating in nature.

In a two-tailed hypothesis about a population mean with a sample size of 100 and α = 0.05, the rejection region would be ___.

Consider the following null and alternative hypotheses: H₀: π $\le$ 0.16 H_a: π > 0.16 These hypotheses ___.

Consider the following null and alternative hypotheses: H_o: µ $\ge$ 67 H_a: µ < 67 These hypotheses ___.

A researcher is testing a hypothesis of a single mean. The critical z value for $\alpha$ =.05 and a two-tailed test is ±1.96. The observed z value from sample data is -2.11. The decision made by the researcher based on this information is to ___ the null hypothesis.

Exam 11: Hypothesis Testing for Single Populations

Suppose the alternative hypothesis in a hypothesis test is: "the population mean is less than 60." If the sample size is 50 and alpha =.05, the critical value of z is ___.

A researcher is testing a hypothesis of a single mean. The critical z value for α\alphaα =.05 and a two-tailed test is ±1.96. The test statistic from sample data is -1.85. The decision made by the researcher based on this information is to ___ the null hypothesis.

When a true null hypothesis is rejected, the researcher has made a Type I error.

When a false \textbf{ false } false null hypothesis is rejected, the researcher has made a Type II error.

If the p value for a hypothesis test is 0.0271, which would be a correct decision?

Suppose you are testing the null hypothesis that a population mean is less than or equal to 80, against the alternative hypothesis that the population mean is greater than 80. If the sample size is 49 and alpha =.10, the critical value of z is ___.

The null hypothesis makes claim about a

Hypotheses are tentative explanations of a principle operating in nature.

In a two-tailed hypothesis about a population mean with a sample size of 100 and α = 0.05, the rejection region would be ___.

Consider the following null and alternative hypotheses: H0: π ≤\le≤ 0.16 Ha: π > 0.16 These hypotheses ___.

Consider the following null and alternative hypotheses: Ho: µ ≥\ge≥ 67 Ha: µ < 67 These hypotheses ___.

A researcher is testing a hypothesis of a single mean. The critical z value for α\alphaα =.05 and a two-tailed test is ±1.96. The observed z value from sample data is -2.11. The decision made by the researcher based on this information is to ___ the null hypothesis.

A researcher is testing a hypothesis of a single mean. The critical z value for $\alpha$ =.05 and a two-tailed test is ±1.96. The test statistic from sample data is -1.85. The decision made by the researcher based on this information is to ___ the null hypothesis.

When a $\textbf{ false }$ null hypothesis is rejected, the researcher has made a Type II error.

Consider the following null and alternative hypotheses: H₀: π $\le$ 0.16 H_a: π > 0.16 These hypotheses ___.

Consider the following null and alternative hypotheses: H_o: µ $\ge$ 67 H_a: µ < 67 These hypotheses ___.

A researcher is testing a hypothesis of a single mean. The critical z value for $\alpha$ =.05 and a two-tailed test is ±1.96. The observed z value from sample data is -2.11. The decision made by the researcher based on this information is to ___ the null hypothesis.