Dear members of the list,
I have panel data looking like this,
Member ID Date Purchase (grams)
1001 20010813 600
1001 20010817 1000
1001 20010824 ...
1002
1002
etc
Does anyone know or have any tips on how to generate a new variabel that
gives the distance in days between the different dates? Eg.
Member ID Date DateD (Distance)
1001 20010813 4
1001 20010817 7
1001 20010824 ...
etc
Based on the new variabel DateD i also want to generate a new variabel
ConsumptionRate that is:
ConsumptionRateA = Purchase/Distance and then RateB=RateA/number of
observations. Eg
Member ID Date Purchase (grams) DateD RateA RateB
1001 20010813 600 4 600/4=150 150+142.8=292.8
1001 20010817 1000 7 1000/7=142.8 150+142.8=292.8
1001 20010824 ... ...
Any help would be greatly appreciated.
Regards,
Mvh,
Alexander Severinsen
markedsfakta as
t: 777 56167
m: 957 83425
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