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Creating indices

Posted: Wed Oct 13, 2010 4:27 pm
by terrya
How can one create indices of the type Ind = 100*y(t)/y(t=n), where n is the particular observation on which the index is based?

Re: Creating indices

Posted: Wed Oct 13, 2010 5:48 pm
by terrya
I should have said that I was looking for something cleverer than just using the actual value, something like the @elem instruction in EViews

Re: Creating indices

Posted: Thu Oct 14, 2010 9:40 am
by TomDoan
set Ind = 100*y(t)/y(n)

or

set IND = 100*y/y(n)

RATS uses series{l} for lags and leads, and series(n) for references to specific entries.

Re: Creating indices

Posted: Fri Jun 03, 2011 12:18 pm
by marcushemma
How would that look if you want to create indices, with reference to a specific entry, e.g. 2000:1, for a number of series?
I tried a number of variations based on a do loop with the series as i = 1,n but that didn't work.

Any suggestions?

Re: Creating indices

Posted: Sat Jun 04, 2011 6:49 pm
by TomDoan
marcushemma wrote:How would that look if you want to create indices, with reference to a specific entry, e.g. 2000:1, for a number of series?
I tried a number of variations based on a do loop with the series as i = 1,n but that didn't work.

Any suggestions?
Something like:

Code: Select all

dofor i = dpfood dpvice dpdura
   set(scratch) i = i{0}/([series] i)(1950:1)
end do i
You need to "cast" the index to a series in order to do the reference to a specific entry.

Re: Creating indices

Posted: Wed Jun 08, 2011 4:02 am
by marcushemma
It works fine until the date for the base of the index but not afterwards. Here's an example that uses some data from the Enders' files.

Code: Select all

cal 1959 1 4
all 2001:1
OPEN DATA "\Enders\Money_dem.xls"
DATA(FORMAT=XLS,ORG=COLUMNS) 1959:01 2001:01 DATE GDP RGDP M2 M3 TB3mo TB1yr
open data a:\money_dem.xls
data(org=obs,format=xls)

dofor i = gdp rgdp m2 m3
    set i =  i{0}/([series] i)(1960:1)
end do i
GRAPH(STYLE=LINE,KEY=BELOW) 4
# GDP
# RGDP
# M2
# m3

pri / gdp rgdp m2 m3

Re: Creating indices

Posted: Wed Jun 08, 2011 7:57 am
by TomDoan
Sorry about that. If you overwrite the series, you need a SCRATCH option on the SET instruction. I've corrected the code in the previous post.