On Saturday, Jul 12, 2003, at 02:33 US/Eastern, Bayard wrote:
I have variables Category, Date and Amount and I need to generate two
new
variables described as follows.
minAmount = smallest Amount in Category as of Date
maxAmount = largest Amount in Category as of Date
Example:
Category Date Amount min max
1 1/1/2001 50 50 50
2 1/1/2001 100 100 100
1 1/2/2001 52 50 52
2 1/2/2001 98 98 100
1 1/3/2001 47 47 52
2 1/3/2001 105 98 105
1 1/4/2001 55 47 55
2 1/4/2001 93 93 105
I've looked, but I can't come up with the right gen or egen commands
and
I've not yet tackled programming. I'm hoping someone can spot some
tricky
way of accomplishing this.
Any help would be appreciated.
ssc install egenmore
. egen maxi=record(amount), by(category)
. egen mini= record(-amount), by(category)
. replace mini=-mini
(8 real changes made)
. list
+--------------------------------------------+
| category date amount maxi mini |
|--------------------------------------------|
1. | 1 1/1/2001 50 50 50 |
2. | 2 1/1/2001 100 100 100 |
3. | 1 1/2/2001 52 52 50 |
4. | 2 1/2/2001 98 100 98 |
5. | 1 1/3/2001 47 52 47 |
|--------------------------------------------|
6. | 2 1/3/2001 105 105 98 |
7. | 1 1/4/2001 55 55 47 |
8. | 2 1/4/2001 93 105 93 |
+--------------------------------------------+
Kit
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