# CH 8 Q

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question
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
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What is measured by the numerator of the z-score test statistic?
The actual distance between M and mu
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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
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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
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Which of the following accurately describes the critical region?
Outcomes with a very low probability if the null hypothesis is true.
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If a hypothesis test produces a z-score in the critical region, what decision should be made?
Reject the null hypothesis
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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 hypotheis
question
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
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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
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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 -
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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
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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
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A hypothesis test involves a comparison of which two elements?
Research results from a sample and a hypothesis about a population
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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
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Which of the following is directly addressed by the null hypothesis?
The population after treatment
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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
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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
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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
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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
question
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
question
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?