st: generating varables

["Max Zamanian" <Max.Zamanian@his.se>]

Hi friends,
For teaching purposes I would like to create variables following
different order of difference equations such as
1.	Yt=bYt-1
2.	Yt=a+bYt-1
3.	Yt=a+bYt-1+cYt-2
etc
This is an example of data series I generate in MS Excel.
1	Sigle nubmer, 1
0,5	Formula: =+E1*0,5
-0,55	=+(E2*0,5)-(E1*0,8)
-0,675	
0,1025	
0,59125	
0,213625	
-0,36619	
-0,35399	
0,115953	
0,341172	
0,077823	
-0,23403	
-0,17927	
0,097585	
0,19221	
0,018037	
-0,14475	
-0,0868	
0,072397	
0,105642	
-0,0051	
-0,08706	
-0,03945	
0,049923	
0,056524	
-0,01168	


For the first one I have got the way doing it, through STATA support,
which is the following:
clear
set obs 10
generate x = 1 * (0.5)^(_n - 1)
list
* end example
Here b=0.5 and the initial value of Y=1. I can of course replace these
values to get different series. Otherwise I do not understand what is
going on, therefore I cannot generate diff eq 2 and 3 above.

I need a general description about how to generate variables like these
and preferably also references to the appropriate menu(s) to get these
variables.

Thanks,
Max

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