We are conducting an impact assessment of a development project is South Asia. The study covers several economic sectors, and for each there is a control group and a test group. We want to know if the changes over time are significantly different for the test and control groups. We have administered a questionnaire at the beginning of the study, and are now going back in to administer a follow-up survey two years later. There are only two points in time -- that of the original survey and that of the followup survey.
Some of the data are clear values (income in time 1 versus income time 2), where we want to know which of the two groups (control or test) has changed the most. Others are various forms of scales -- such as 1=Very good, 2=Good,3=Neither Good nor Bad, 4=Bad, 5 = Very Bad.-- where we want to see if perceptions have changed over time and which group has changed the most.
I know that I can do this through a rather cumbersome process involving comparisons of group means, but I'm wondering if there are routines in Stat that are specifically designed to do this. It would seem to be a study of panel data, but in reading the manual I'm not certain that that is correct.
Any suggestions would be appreciated,
John
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