"Webb.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
>
REPLY:
This is sort of cludgy, but it seems to work:
sort date category
capture drop order
gen byte order = _n
capture drop min
capture drop max
sort category date
foreach X of new min max {
by category : gen `X' = amount[1]
}
qui by category : replace min = amount if amount < min[_n-1]
qui by category : replace min = min[_n-1] if min > min[_n-1]
qui by category : replace max = amount if amount > max[_n-1]
qui by category : replace max = max[_n-1] if max < max[_n-1] & _n >1
sort order
list
john hennen
Boston
>
> 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.
>
> Bayard
> *
> * For searches and help try:
> * http://www.stata.com/support/faqs/res/findit.html
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
Any information, including protected health information (PHI), transmitted in this email is intended only for the person or entity to which it is addressed and may contain information that is privileged, confidential and or exempt from disclosure under applicable Federal or State law. Any review, retransmission, dissemination or other use of or taking of any action in reliance upon, protected health information (PHI) by persons or entities other than the intended recipient is prohibited. If you received this email in error, please contact the sender and delete the material from any computer.
