Chapter 8 of independence sample t-test
1. A social work agency specializes in treating families in crisis. One of their goals is to increase the stability of the family, reducing the frequency of times of distress. The common practice in the agency is for a team of crisis counselors to respond in those times that families are in distress, hopefully helping them to learn healthier ways to cope with the challenges they face. A new director has arrived, and wants to test a new kind of intervention. For this intervention, the social work counselors will meet regularly with clients to educate them on stress and conflict management strategies, in addition to being available on an as needed basis. The director decides to test the new intervention, by assigning one group of families to be in the 'control' condition, and simply receive the usual assistance, and another group of families to be in the 'intervention' condition, who also receive the regularly scheduled stress and conflict management education. The director wants to know whether families who receive the intervention score better on a family stability test than families who do not receive the intervention.
*Please see the attachment for the image*
a. What hypothesis is being tested here? (1 pt)
b. What are the means for the two groups? (1 pt)
c. Examine Levene's Test for Equality of Variance. Is it safe to conclude that homogeneity of variance exists here? What number tells you this? (2 pts) =
d. Write your result in the three sentence format. (3 pts).
2. Suppose that the director is concerned that scores may have been influenced by the time of year that families received intervention. Specifically, she fears that it may be that more families in the intervention group were tested in the summer, and more in the control group were tested during the school year. She decides to run another analysis to determine whether families who were tested during the school year score differently on the family stability test than families who were tested during the summer.
*Please see the attachment for the image*
a. What hypothesis is being tested here? (1 pt) =
b. What are the means for your two groups? (2 pts) =
c. Examine Levene's Test for Equality of Variance. Is it safe to conclude that you have homogeneity of variance here? What number tells you this? (2 pts) =
d. Write your result in the three sentence format. (3 pts) =
3. All of the components that go into the t equation are presented in the output for each question above. You do not have to do the calculations, but write out the equation here, filling in the numbers that correspond to each symbol in the t-equation for question 2. (4 pts)
*Please see the attachment for the image*
Taking It Further
4. What is the confidence interval of the difference for question 1? What exactly does this represent? (4 pts)
5. What is the confidence interval of the difference for question 2? What exactly does this represent? (4 pts)
6. When heterogeneity of variance exists in an analysis, does this have any impact on the confidence interval of the difference? If so, does it make the confidence interval wider or narrower than when homogeneity of variance exists? (2 pts)
Chapter 8 of independence sample t-test
1. A social work agency specializes in treating families in crisis. One of their goals is to increase the stability of the family, reducing the frequency of times of distress. The common practice in the agency is for a team of crisis counselors to respond in those times that families are in distress, hopefully helping them to learn healthier ways to cope with the challenges they face. A new director has arrived, and wants to test a new kind of intervention. For this intervention, the social work counselors will meet regularly with clients to educate them on stress and conflict management strategies, in addition to being available on an as needed basis. The director decides to test the new intervention, by assigning one group of families to be in the 'control' condition, and simply receive the usual assistance, and another group of families to be in the 'intervention' condition, who also receive the regularly scheduled stress and conflict management education. The director wants to know whether families who receive the intervention score better on a family stability test than families who do not receive the intervention.
*Please see the attachment for the image*
