st: Calculating variable-averages of time-spans (laid out case by case via variables)

[Wolfgang Feudenheim <wg_feudenheim@web.de>]

Hi,

I am currently working on an analysis of economic data in OECD-countries. For each country, I separately fixed a key-year. For this specific year and the two preceding years I want to read out averages of economic indicators such as "GDP/capita" etc.

In the following, I try to illustrate my problems with the help of the example dataset 
"National Longitudinal Survey.  Young Women 14-26 years of age in 1968" by pretending I was interested in the average workload before the occurance of a burnout (sorry, couldn't make up any more positive scenario ...). Unfortunately, the time data is not available on a year-by-year-basis but in irregular steps. Therefore, I just observe one specific year and its preceding year. I am running my analysis on

-Stata/IC 11.1 for Mac (64-bit Intel)
-Born 04 Nov 2010

Here is the code:

-use http://www.stata-press.com/data/r11/nlswork.dta, clear
-*Add Burnout-Values to Dataset*
-gen burnoutyear=.
-replace burnoutyear=73 if idcode==1
-replace burnoutyear=72 if idcode==2

-*Generate Variable for all observations of one person (idcode) that presents the average of weeks worked in burnout-year and* 
-*burnout-preceding year*
-egen avworkload_b=mean(wks_work[_n]+wks_work[_n-1]) if (year==burnoutyear)&(idcode[_n]==idcode[_n-1])


The problems that occur are the following:

1. For both, "idcode==1" and "idcode==2", the wrong result, namely "25" is displayed. The average values should however be "27 and "17.5".

2. The variable "avworkload_b" is only inserted into the dataset for the year indicated by "burnoutyear" for the respective "idcode". I want to have this value displayed for all years of each "idcode".

Thanks in advance!

Wolfgang
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