PSM EXAM 2
The alpha level determines the risk of a Type II error. (T/F) - ANSWER False
What is the consequence of a Type II error? - ANSWER Concluding that a treatment
has no effect when it really does
A researcher conducts a hypothesis test to evaluate the effect of a treatment. The
hypothesis test produces a z-score of z = 2.37. Assuming that the researcher is using a
two-tailed test, what decision should be made? - ANSWER The researcher should
reject the null hypothesis with α = .05 but not with α = .01
What is the relationship between the alpha level, the size of the critical region, and the
risk of a Type I error? - ANSWER As the alpha level increases, the size of the critical
region increases and the risk of a Type I error increases.
In general, the null hypothesis states that the treatment has no effect on the population
parameter being studied. (T/F) - ANSWER True
A two-tailed hypothesis test is being used to evaluate a treatment effect with α = .01. If
the sample data produce a z-score of z = 2.24, then what is the correct decision? -
ANSWER Fail to reject the null hypothesis and conclude that the treatment has no
effect.
Even if a treatment has an effect, it is still possible to obtain a sample mean that is very
similar to the original population mean. What outcome is likely if this happens? -
ANSWER Fail to reject H0 and make a Type II error.
A research report includes the statement, z = 2.13, p < .05. For this hypothesis test, the
used null hypothesis is rejected using an alpha level of α = .05.(T/F) - ANSWER True
A sample of n = 16 individuals is selected from a population with μ = 60 and σ = 6 and a
treatment is administered to the sample. After treatment, the sample mean is M = 63.
What is the value of Cohen's d for this sample? - ANSWER 0.50
A researcher is conducting a study 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 a
= .01, then which of the following correctly identifies the critical region? - ANSWER z >
2.33
By selecting a larger alpha level, a researcher is ____. - ANSWER increasing the risk of
a Type I error
A significant treatment effect indicates that a large treatment effect was found. (T/F) -
ANSWER False
The alpha level determines the risk of a Type II error. (T/F) - ANSWER False
What is the consequence of a Type II error? - ANSWER Concluding that a treatment
has no effect when it really does
A researcher conducts a hypothesis test to evaluate the effect of a treatment. The
hypothesis test produces a z-score of z = 2.37. Assuming that the researcher is using a
two-tailed test, what decision should be made? - ANSWER The researcher should
reject the null hypothesis with α = .05 but not with α = .01
What is the relationship between the alpha level, the size of the critical region, and the
risk of a Type I error? - ANSWER As the alpha level increases, the size of the critical
region increases and the risk of a Type I error increases.
In general, the null hypothesis states that the treatment has no effect on the population
parameter being studied. (T/F) - ANSWER True
A two-tailed hypothesis test is being used to evaluate a treatment effect with α = .01. If
the sample data produce a z-score of z = 2.24, then what is the correct decision? -
ANSWER Fail to reject the null hypothesis and conclude that the treatment has no
effect.
Even if a treatment has an effect, it is still possible to obtain a sample mean that is very
similar to the original population mean. What outcome is likely if this happens? -
ANSWER Fail to reject H0 and make a Type II error.
A research report includes the statement, z = 2.13, p < .05. For this hypothesis test, the
used null hypothesis is rejected using an alpha level of α = .05.(T/F) - ANSWER True
A sample of n = 16 individuals is selected from a population with μ = 60 and σ = 6 and a
treatment is administered to the sample. After treatment, the sample mean is M = 63.
What is the value of Cohen's d for this sample? - ANSWER 0.50
A researcher is conducting a study 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 a
= .01, then which of the following correctly identifies the critical region? - ANSWER z >
2.33
By selecting a larger alpha level, a researcher is ____. - ANSWER increasing the risk of
a Type I error
A significant treatment effect indicates that a large treatment effect was found. (T/F) -
ANSWER False
