A study was
undertaken in relation to obsessive-compulsive disorder (OCD) to determine the
impact of this disorder on family members who reside with the sufferer.
typically family members begin to accommodate such behaviours and in essence,
are drawn into the rituals associated with the
disorder. this then causes those family members to perceive a burden which
ultimately effects quality of life. Data concerning OCD and it’s impact on
family members measured the following: Severity of OCD perceived by a family member Accommodation behaviours
Perceived bürden Perceived quality of life Subsequently a regression and was
conducted to test the relationship between these variables.
(a) If a correlation matrix was generated for
each of the variables, what indications
would you be looking for? (WORTH 4 MARKS)
(b) Analysis
of the data for the above study showed that the adjusted r-square was 0.49.
Explain carefully what this statistic measures. How do you interpret this
result? (WORTH 4 MARKS)
(c)In regression
analysis
what is the difference between Enter and
Stepwise method of analysis? Which is the preferred method and why? (WORTH 4
MARKS)
(d)
Multicollinearity can spoilt estimates in a regression. On the other hand
psychological constructs may reasonably be considered to correlate. Explain how you
would assess multicollinearity among the independent variables for the study
above? What action would you take to remedy it? (WORTH 4 MARKS)
(e) Participants in the above
study were classified in terms of their perception of the
severity of OCD in a family member as follows:
Low = 1 medium = 2 High = 3 If low is the reference group show how dummy
variables could be created and coded for a regression analysis to determine the
relationship between perceived severity of OCD and perceived
quality of life. Explain the logic of this
coding. (WORTH 4 MARKS).