### Z-Score Test, Hypothesis Test, Rejecting The Null Hypothesis, Sample, Population – Quiz

The key terms in these Statistic chapters include Z-Score Test, Hypothesis Test, Data, Sample, Rejecting The Null Hypothesis, Population, Sample Mean, Two-Tailed Test, Population Mean, Two-Tailed Hypothesis, Null Hypothesis, Treatment Effect, Critical Region, Statistical Decision, Probability.

What is measured by the numerator of the z-score test statistic?

**The actual distance between M and mu**

Which of the following accurately describes a hypothesis test?

**An inferential technique that uses the data from a sample to draw inferences about a population**

A researcher selects a sample and administers a treatment to the individuals in the sample. If the sample is used for a hypothesis test, what does the null hypothesis (H0) say about the treatment?

**The treatment has no effect on the scores**

For a hypothesis test evaluating the effect of a treatment on a population mean, what basic assumption is made concerning the treatment effect?

**If there is a treatment effect, it will add/subtract a constant to each score**

The critical boundaries for a hypothesis test are z=+1.96/-1.96. If the z-score for the sample data is z=-1.90, what is the correct statistical decision?

**Fail to reject the null hypothesis**

A class consists of 10 males and 30 females. A random sample of n = 3 students is selected. If their first two students are both females, what is the probability that the third student is a male?

a) 10/37

b) 10/38**c) 10/40**

d) 9/38

All probabilities can be expressed as decimal values ranging from 0 to 1.00.

**True**

Which of the following accurately describes the critical region?

**Outcomes with a very low probability if the null hypothesis is true.**

If a hypothesis test produces a z-score in the critical region, what decision should be made?

**Reject the null hypothesis**

A researcher administers a treatment to a sample of participants selected from a population with a population mean of 80. If a hypothesis test is used to evaluate the effect of the treatment, which combination of factors is most likely to result in rejecting the null hypothesis?

**A sample mean much different than 80 for a large sample**

A researcher administers a treatment to a sample of participants selected from a population with a population mean of 80. If the researcher obtains a sample mean of M=88, which combination of factors is most likely to result in rejecting the null hypothesis?

**Standard deviation of 5, alpha =.05**

A researcher is conducting an experiment to evaluate a treatment that is expected to increase the scores for individuals in a population that is known to have a mean of 80. The results will be examined using a one-tailed hypothesis test. Which of the following is the correct statement of the null hypothesis?

**mu is less than or equal to 80 Mu < 80**

A researcher expects a treatment to increase the scores for individuals in a population. The treatment is evaluated using a one-tailed hypothesis test, and the test produces z=+2.40. Based on this result, what is the correct statistical decision?

**The researcher should reject the null hypothesis with either alpha=.05 or .01**

A researcher evaluates a treatment effect using a two-tailed hypothesis test with alpha=.05, and the decision is to reject the null hypothesis. If the researcher switched to a one-tailed test using the same sample, what decision would be made?

**Definitely reject the null hypothesis with alpha=.05 and maybe reject alpha=.01**

A hypothesis test involves a comparison of which two elements?

**Research results from a sample and a hypothesis about a population**

What is measured by the denominator of the z-score test statistic?

**The average distance between M and mu that would be expected if H0 was true**

Which of the following is directly addressed by the null hypothesis?

**The population after treatment**

A researcher evaluates a treatment effect using a one-tailed hypothesis test with alpha = 0.05, and the decision is to reject the null hypothesis. If the researcher switched to a two-tailed test using the same, sample, what decision would be made?

**Might reject the null hypothesis with alpha = 0.05 but might not**

For a hypothesis test evaluating the effect of a treatment on a population mean, what basic assumption is made concerning the treatment effect?

**If there is a treatment effect, it will add/subtract a constant to each score**

The critical boundaries for a hypothesis test are z=+1.96/-1.96. If the z-score for the sample data is z=-1.90, what is the correct statistical decision?

**Fail to reject the null hypothesis**

Which of the following accurately describes the critical region?

**Outcomes with a very low probability if the null hypothesis is true.**

If a hypothesis test produces a z-score in the critical region, what decision should be made?

**Reject the null hypothesis**

A researcher administers a treatment to a sample of participants selected from a population with a population mean of 80. If the researcher obtains a sample mean of M=88, which combination of factors is most likely to result in rejecting the null hypothesis?

**Standard deviation of 5, alpha =.05**

A researcher evaluates a treatment effect using a two-tailed hypothesis test with alpha=.05, and the decision is to reject the null hypothesis. If the researcher switched to a one-tailed test using the same sample, what decision would be made?

**Definitely reject the null hypothesis with alpha=.05 and maybe reject alpha=.01**

A hypothesis test involves a comparison of which two elements?

**Research results from a sample and a hypothesis about a population**

A researcher evaluates a treatment effect using a one-tailed hypothesis test with alpha = 0.05, and the decision is to reject the null hypothesis. If the researcher switched to a two-tailed test using the same, sample, what decision would be made?

**Might reject the null hypothesis with alpha = 0.05 but might not**

A researcher selects a sample and administers a treatment to the individuals in the sample. If the sample is used for a hypothesis test, what does the alternative hypothesis (H1) say about the treatment?

**The treatment causes a change in the scores**

With alpha=.05, how are the boundaries for the critical region determined>

**Boundaries are drawn so there is 2.5% (.025) in each tail of the distribution**

A two-tailed hypothesis is being used to evaluate a treatment effect with alpha=.05. If the sample data produce a z-score of z=-2.24, what is the correct decision?

**Reject the null hypothesis and conclude that that the treatment has an effect**

A two-tailed hypothesis test is being used to evaluate a treatment effect. The hypothesis test produces a z-score of 2.37. Assuming that the researcher is using a two-tailed test, what decision should be made?

**The researcher should reject the null hypothesis with a alpha =0.05 but not with an alpha= 0.01**

A researcher administers a treatment to a sample of participants selected from a population with a mean of 80. If the researcher obtains a sample mean of 88, which combination of factors is most likely to result in rejecting the null hypothesis?

**A sample mean much different than 8- with alpha = 0.05**

Which of the following is a requirement for a random sample?

a) every individual has an equal chance of being selected

b) the probabilities cannot change during a series of selections

c) there must be sampling with replacement**d) all of the other 3 choices are correct**

A class consists of 10 males and 30 females. If one student is randomly selected from the class, what is the probability of selecting a male?

a) 10/30**b) 10/40**

c) 1/10

d) 1/40

A researcher administers a treatment to a sample of participants selected from a population with a mean of 80. If the researcher obtains a sample mean of 88, which combination of factors is most likely to result in rejecting the null hypothesis?

**Standard deviation = 5, n = 50**

A researcher conducts a hypothesis test to evaluate the effect of a treatment that is expected to increase scores. The hypothesis test produces a z-score of 2.27. If the researcher is using a one tailed test with alpha = 0.01, then which of the following correctly identifies the critical region?

**z>2.33**

A researcher is conducting an experiment to evaluate a treatment that is expected to increase the scores for individuals in a population. If the researcher uses a one-tailed test with alpha = 0.01, then which of the following correctly identifies the critical region?

**z>2.33**

A researcher evaluates a treatment effect using a one-tailed hypothesis test with alpha = 0.05, and the decision is to reject the null hypothesis. If the researcher switched to a two-tailed test using the same, sample, what decision would be made?

**Might reject the null hypothesis with alpha = 0.05 but might not**

For a hypothesis test evaluating the effect of a treatment on a population mean, what basic assumption is made concerning the treatment effect?

**If there is a treatment effect, it will add/subtract a constant to each score**

The critical boundaries for a hypothesis test are z=+1.96/-1.96. If the z-score for the sample data is z=-1.90, what is the correct statistical decision?

**Fail to reject the null hypothesis**

Which of the following accurately describes the critical region?

**Outcomes with a very low probability if the null hypothesis is true.**

If a hypothesis test produces a z-score in the critical region, what decision should be made?

**Reject the null hypothesis**

A researcher administers a treatment to a sample of participants selected from a population with a population mean of 80. If the researcher obtains a sample mean of M=88, which combination of factors is most likely to result in rejecting the null hypothesis?

**Standard deviation of 5, alpha =.05**

A researcher evaluates a treatment effect using a two-tailed hypothesis test with alpha=.05, and the decision is to reject the null hypothesis. If the researcher switched to a one-tailed test using the same sample, what decision would be made?

**Definitely reject the null hypothesis with alpha=.05 and maybe reject alpha=.01**

A hypothesis test involves a comparison of which two elements?

**Research results from a sample and a hypothesis about a population**

**Might reject the null hypothesis with alpha = 0.05 but might not**

Which of the following accurately describes a hypothesis test?

**An inferential technique that uses the data from a sample to draw inferences about a population**

What is measured by the numerator of the z-score test statistic?

**The actual distance between M and mu**

Which of the following accurately describes a hypothesis test?

**An inferential technique that uses the data from a sample to draw inferences about a population**

A researcher selects a sample and administers a treatment to the individuals in the sample. If the sample is used for a hypothesis test, what does the null hypothesis (H0) say about the treatment?

**The treatment has no effect on the scores**

**If there is a treatment effect, it will add/subtract a constant to each score**

**Fail to reject the null hypothesis**

A class consists of 10 males and 30 females. A random sample of n = 3 students is selected. If their first two students are both females, what is the probability that the third student is a male?

a) 10/37

b) 10/38**c) 10/40**

d) 9/38

**Definitely reject the null hypothesis with alpha=.05 and maybe reject alpha=.01**

A hypothesis test involves a comparison of which two elements?

**Research results from a sample and a hypothesis about a population**

What is measured by the denominator of the z-score test statistic?

**The average distance between M and mu that would be expected if H0 was true**

Which of the following is directly addressed by the null hypothesis?

**The population after treatment**

**Might reject the null hypothesis with alpha = 0.05 but might not**

Which of the following accurately describes the critical region?

**Outcomes with a very low probability if the null hypothesis is true.**

If a hypothesis test produces a z-score in the critical region, what decision should be made?

**Reject the null hypothesis**

**Standard deviation of 5, alpha =.05**