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RE: st: Calculating cumulative value over several observations
From 
 
"Clyde Schechter" <[email protected]> 
To 
 
[email protected] 
Subject 
 
RE: st: Calculating cumulative value over several observations 
Date 
 
Sat, 11 Dec 2010 10:47:13 -0800 
I think this will get you what you want:
levelsof buyer, local(buyers)
levelsof seller, local(sellers)
local participants: list buyers | sellers
sort market period observation
foreach p of local participants {
	by market period (observation): gen M`p' = sum(price*(seller==`p')) -
sum(price*(buyer==`p'))
	by market period (observation): gen A`p' = sum(buyer == `p') - sum(seller
== `p')
}
Note:  If your buyers and sellers constitute the integers between 1 and P
for some P, then you don't need to do the -levelsof- commands and you can
replace the foreach loop with a forvalues p = 1/P loop.
By the way, just out of curiosity, if everybody starts out with no money
and no apples, how do they make these trades?
Clyde Schechter, MA MD
Associate Professor of Family & Social Medicine
Please note new e-mail address: [email protected]
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