Question

An experimenter wants to know if having a pet or friend present while taking a stressful math test helps reduce anxiety. She recruits 120 people to participate in the study and each person takes a difficult math test under a strict time limit. The participants are also randomly assigned to take the test alone, with a friend in the room, or with a therapy dog in the room. After taking the test, participants completed a survey that assessed how stressful they found the test. Scores on the stress survey were measured on an interval scale and higher numbers indicated greater stress.

Use the SPSS ouput below to fill in the summary table values.

Use the SPSS ouput below to fill in the summary table values. Source of Variance SS df MS F n2 2 decimal places 2 decimal places 2 decimal places 2 decimal places Between treatments 2 decimal places 2 decimal places Within treatments (error) 2 decimal places Total Descriptive Statistics Dependent Variable: Stress Group Mean Std. Deviation N Dog 40.8430 11.26156 40 Friend 57.5624 12.76529 40 Alone 52.0676 13.70089 40 Total 50.1577 14.32861 120

2. Identify which of the following results statements best describes the results of this study for the overall F test results and the post hoc analyses.

	A.	Significant differences were not found for stress test scores based on who was present when taking a stressful math test, F(2, 119) = 18.25, p < .001, η2p = .24. There were not differences in stress scores when participants had a dog present while taking the stressful math test (M = 40.84, SD = 11.26) versusa friend being present (M = 57.56, SD = 12.76), HSD = -16.72, p < .001 or versus being alone (M = 52.07, SD = 13.70), HSD = -11.22, p < .001. Also, there was no significant difference in stress test scores when a friend was present versus being alone while taking a stressful math test, HSD = 5.49, p = .130.
	B.	Significant differences were found for stress test scores based on who was present when taking a stressful math test, F(2, 120) = 18.25, p < .001, η2p = .24. Stress scores were lowest when participants had a dog present while taking the stressful math test (M = 40.84, SD = 11.26) versus a friend being present (M = 57.56, SD = 12.76), HSD = -16.72, p < .001 and versus being alone (M = 52.07, SD = 13.70), HSD = -11.22, p < .001. There was no significant difference in stress test scores when a friend was present versus being alone while taking a stressful math test, HSD = 5.49, p = .130.
	C.	Significant differences were found for stress test scores based on who was present when taking a stressful math test, F(2, 117) = 18.25, p < .001, η2p = .24. Stress scores were highest when participants had a dog present while taking the stressful math test (M = 40.84, SD = 11.26) versus a friend being present (M = 57.56, SD = 12.76), HSD = -16.72, p < .001 and versus being alone (M = 52.07, SD = 13.70), HSD = -11.22, p < .001. Stress test scores were significantly lower when a friend was present versus being alone while taking a stressful math test, HSD = 5.49, p = .130.
	D.	Significant differences were found for stress test scores based on who was present when taking a stressful math test, F(2, 117) = 18.25, p < .001, η2p = .24. Stress scores were lowest when participants had a dog present while taking the stressful math test (M = 40.84, SD = 11.26) versus a friend being present (M = 57.56, SD = 12.76), HSD = -16.72, p < .001 and versus being alone (M = 52.07, SD = 13.70), HSD = -11.22, p < .001. There was no significant difference in stress test scores when a friend was present versus being alone while taking a stressful math test, HSD = 5.49, p = .130.

3. When interpreting SPSS output of an ANOVA, how can you determine if you should reject the null hypothesis without knowing the F-critical value?

	A.	The p value is less than the α level of .05.
	B.	The effect size is greater than the α level of .05.
	C.	The effect size is less than the α level of .05.
	D.	The p value is greater than the α level of .05.

Answer 1

Que.2

Significant differences were found for stress test scores based on who was present when taking a stressful math test, F(2, 117) = 18.25, p < .001, η²_p = .24. Stress scores were lowest when participants had a dog present while taking the stressful math test (M = 40.84, SD = 11.26) versus a friend being present (M = 57.56, SD = 12.76), HSD = -16.72, p < .001 and versus being alone (M = 52.07, SD = 13.70), HSD = -11.22, p < .001. There was no significant difference in stress test scores when a friend was present versus being alone while taking a stressful math test, HSD = 5.49, p = .130.

Que.3

The p value is less than the α level of .05.