# st: RE: vececm

 From Joly.Patrick@ic.gc.ca To statalist@hsphsun2.harvard.edu Subject st: RE: vececm Date Fri, 27 Sep 2002 10:45:41 -0400

```Konstantin Komissarov [mailto:kbpf@mail.com] wrote

>> How can I impose restriction on cointegrating
>> vectors using vececm command?

The help file for -vececm- states that:

restricted(numlist) imposes restrictions on one or more
of the cointegrating vectors.  (lrjtest with option
restrict must have been previously conducted.)
numlist refers to those specific vectors which are
to be restricted, that is, type restricted(2 4) to
use restricted vectors 2 and 4 as computed by
lrjtest.

Example,

use http://fmwww.bc.edu/ec-p/data/macro/wgmacro.dta, clear
johans investment income consumption, lags(2)
lrjtest investment, c(1) restrict
vececm, cir(1) sm(1) lags(3) restrict(1)

If inference leads you to believe that there are 2 cointegrating
relationships
but you wanted to restrict only the second vector, you could (at your own
peril) do

johans investment income consumption, lags(2)
lrjtest investment, c(2) restrict
vececm, cir(2) sm(1) lags(3) restrict(2)

By 'at your own peril' I mean that -vececm- is meant to be enabling in the
sense that it allows you to select all or some of the restricted vectors
from -lrjtest- (the remaining vectors are those calculated by -johans-).
That said, -lrjtest- only tests the hypothesis that a subset of variables do
not appear in ANY of the cointegrating relations.  Therefore, it is
advisable to select ALL of the restricted vectors if one is to apply any
restrictions at all, i.e. if there are two cointegrating relations, type

lrjtest investment, c(2) restrict
vececm, cir(2) sm(1) lags(3) restrict(1 2)

Patrick Joly
joly.patrick@ic.gc.ca
pat.joly@utoronto.ca
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```