Re: st: Rearranging Variables

[sokela <alekos.bibudis@PHIL.TU-CHEMNITZ.DE>]

Thanks for your responses so far .

Johannes, do you mean 12 months for each wave?

Anyway, I am not looking for the sum of unemployment months within the 
last 12 months before the interview, but for the number of changes of 
status in that time. I want to see if it makes a difference using the 
latter one compared to the sum of unemployed months regarding the 
influence on actual job-uncertainty.

I am looking at people who are actually employed. In the first step, 
using a ologit-model I want to look at the influence several variables 
(Household-Income, Education, Age, Sex beside other variables) have on 
the actual perception of job-uncertainty.
The list of independent variables also includes the sum of months 
unemploeyd in the year before the interview.
(I also plan to look at the influence the time a person is already 
employed at the same company has on job-uncertainty, assuming the longer 
a person already works at one place, the lower the perception of 
insecurity.)

My suspicion is that its not just how long you have been unemployed, but 
also how stable you status it (or in other words on the experience of 
instability in the past), that has an influence on the dependent variable.

Therefore I believe I will have to calculate the dummyvariables 
mentioned in my earlier post.

Alekos


I think the problem ist that interview dates vary, so you collect
information from a maximum of 23 months for each wave (Interview date
January until December).
You could reshape your data not only by person-year observations but by
person-month observations per row. Use an index starting with 1 in January
1999, use the same index for your interview dates and as far as I know
those unemployment spells are also indexed in a similar way in GSOEP.

Use the person-months rows to generate your aggregated variable
(unemployment months within the last 12 months before the interview date)
with time-series operators e.g.,  and then reshape it back to person-year
rows.

Johannes


----------------------
Johannes Geyer
Deutsches Institut für Wirtschaftsforschung (DIW Berlin)
German Institute for Economic Research
Department of Public Economics
DIW Berlin
Mohrenstraße 58
10117 Berlin
Tel: +49-30-89789-258
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