One Sample t Test and Quiz

One Sample t Test and Quiz

QUESTION 1

1. Two researchers (A and B) compute a one-sample t test. For both tests, the mean difference between the sample and value stated in the null hypothesis is 5, but the standard error is smaller for Researcher A. Which test is more likely to result in a decision to reject the null hypothesis?

   	a.	The likelihood is the same for both researchers.
   	b.	Researcher B.
   	c.	Researcher A.
   	d.	There is not enough information to answer this question.

10 points

QUESTION 2

1. A researcher selects a sample of 16 women and asks them to rate how important a sense of humor is in someone they want a long-term relationship with. She records scores averaging 1.6±0.8 (M±SD) on a rating scale from -3 (not important at all) to +3 (very important). Assuming that an average score of 0 is the null hypothesis, test whether or not women find this trait important at a .05 level of significance.

   	a.	Women did not find this trait to be important, p > .05.
   	b.	Women found this trait to be important, and this result was significant, t(16) = 8.00, p < .05.
   	c.	There is not enough information to answer this question.
   	d.	Women found this trait to be important, and this result was significant, t(15) = 8.00, p < .05.

10 points

QUESTION 3

1. The t distribution is similar to the z distribution except:

   	a.	It is associated with greater variability.
   	b.	It is characterized by “thicker” tails compared with the z distribution.
   	c.	It is associated with scores being more likely in the tails of the distribution.
   	d.	All of the above.

10 points

QUESTION 4

1. Two researchers (A and B) compute a two-independent sample t test. For both tests, the standard error is the same, but the mean difference between the groups is larger for Researcher A. Which test is more likely to result in a decision to reject the null hypothesis?

   	a.	There is not enough information to answer this question.
   	b.	Researcher A.
   	c.	Researcher B.
   	d.	The likelihood is the same for both researchers.

10 points

QUESTION 5

1. As a requirement for the t test, researchers compute any type of t test with samples selected from populations in which:

   	a.	The population is the same size as the sample.
   	b.	The population size is very large.
   	c.	The population variance is known.
   	d.	The population variance is unknown.

10 points

QUESTION 6

1. A researcher conducts a study and concludes that a new behavioral health treatment program significantly reduces one’s risk for disease compared with risk levels in the general population (d = -0.64). Interpret the size of this effect.

   	a.	64% of the variability in risk level can be accounted for by the new treatment.
   	b.	Risk levels in the population shifted 0.64 standard deviations above the mean.
   	c.	Risk levels in the population shifted 0.64 standard deviations below the mean.
   	d.	64% of the new treatment can be accounted for by the risk levels.

10 points

QUESTION 7

1. Which of the following summarizes a t test that was significant and associated with a large effect size?

   	a.	T(30) = 1.03, p < .05, d = .20.
   	b.	T(60) = 1.76, p < .05, d = .45.
   	c.	T(12) = 2.95, p < .05, d = .82.
   	d.	T(22) = 3.02, p < .05, d = .36.

10 points

QUESTION 8

1. Is a one-sample t test reported differently for one-tailed and two-tailed tests?

   	a.	It depends on whether the results were significant.
   	b.	It can be reported differently when the effect size is large.
   	c.	Yes, only significant results for a two-tailed test are reported.
   	d.	No, the same values are reported.

10 points

QUESTION 9

1. A researcher conducts two t tests. Test 1 is a one-tailed test with a smaller sample size at a .05 level of significance. Test 2 is a one-tailed test with a larger sample size at a .05 level of significance. What do you know about the critical values for each test?

   	a.	It depends; there is not enough information to answer this question.
   	b.	Test 2 is associated with smaller critical values.
   	c.	Each test is associated with the same critical values.
   	d.	Test 1 is associated with smaller critical values.

10 points

QUESTION 10

1. Two researchers (A and B) compute a one-sample t test. For both tests, the standard error is the same, but the mean difference between the sample and value stated in the null hypothesis is smaller for Researcher A. Which test is more likely to result in a decision to reject the null hypothesis?

   	a.	Researcher A.
   	b.	The likelihood is the same for both researchers.
   	c.	Researcher B.
   	d.	There is not enough information to answer this question.