1 A researcher selects a sample of 16 women and asks them to

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 found this trait to be important, and this result was significant, t(16) = 8.00, p < .05.

b. Women found this trait to be important, and this result was significant, t(15) = 8.00, p < .05.

c. Women did not find this trait to be important, p > .05.

d. There is not enough information to answer this question.

2. A researcher reports a significant effect in some population. If he computes both an eta-squared and an omega-squared effect size estimate, then which estimate will be the largest?

a. eta-squared

b. omega-squared

c. It depends on the sample size.

d. It depends on the value of the t statistic.

3. It is most appropriate to report effect size with a significant result. Why is it generally inappropriate to report effect size with insignificant results?

a. Because insignificant results will always have an effect size equal to 0.

b. Because insignificant results indicate that an effect size is also insignificant.

c. Because it makes little sense to report the size of an effect that you just concluded doesn\'t exist.

d. Because the probability of the size of an effect varies depending on the significance of the result.

4. In a sample of 20 participants, a researcher estimates the 95% CI for a sample with a mean of M = 5.4 and an estimated standard error (^SM) of 1.6. What is the lower confidence limit for this interval?

a. 2.1

b. 3.8

c. 7.0

d. 8.8

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

a. No, the same values are reported.

b. It depends on whether the results were significant.

c. Yes, only significant results for a two-tailed test are reported.

d. It can be reported differently when the effect size is large.

6. You read about a study testing whether night shift workers sleep the recommended 8 hours per day. Assuming that the population variance of sleep (per day) is unknown, what type of t test is appropriate for this study?

a. one-sample t test

b. two-independent sample t test

c. There is not enough information to answer this question.

7. A key difference between a t statistic and a z statistic is that the standard error is ________ to compute a t statistic.

a. removed

b. replaced

c. estimated

d. placed in the numerator

8. A researcher reports that stress levels among nurses are higher compared to stress levels in the general population, t(20) = 2.086, p = .05 (d = .12). Was this a one-tailed or a two-tailed test?

a. One-tailed test because the p value is equal to .05

b. Two-tailed test because the p value is equal to .05

c. It could be a one-or a two-tailed test

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

Solution

Answer to question# 1)

We got Sample Mean x bar = 1.6

Sample standard deviation s = 0.8

Population mean = 0

sample size = 16

df = 16-1 = 15

it is a two tailed test

.

Formula of test statistic :

t = (x bar - M) / (s/sqrt(16))

t = (1.6-0) / (0.8/sqrt(16))

t = 8

.

The P value for t = 8 , df = 15, two tailed test can be found using the excel command

=t.dist.2t(8,15)

We get P value = 0.00000086

.

Inference since the P value < 0.05 , we reject the null

Conclusion: Thus we conclude that the sense of humor is an important factor for female

Thus the correct answer choice is B