Weighting Coefficients

[cmgconsulting]

Is it possible to force a coefficient to be a specific value in OLS? For example, if I want C(2) [that is, the coefficient for log(price)] to be -1.5, can I do that?

Here is my equation:

equation {%eqname}
{%eqname}.ls log(ssu) c log(price) log(stores) @trend(1) @expand(period,@dropfirst) easter


Also, is it possible to do this from the PROC menu anywhere or without programming?

[EViews Gareth]

You can always write out an equation as an expression rather than by list (both in a program and via the dialogs).

i.e.

Code: Select all

ls y c x1 x2

is the same thing as

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ls y = c(1)+c(2)*x1+c(3)*x2

When written out as an expression you can replace a coefficient with a value, i.e.:

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ls y = c(1)+0.5*x1 + c(2)*x2

Unfortunately, for you, you cannot use the @expand keyword when writing out an equation by expression, so you'll have to expand it manually.


Of course the alternative, if you want to write out your equation by list, is simply to write your equation as:

Code: Select all

ls log(ssu)+1.5*log(price) c log(stores) @trend(1) @expand(period,@dropfirst) easter

[cmgconsulting]

Can I force a negative sign on C(2).

Is it possible to do this without manually expanding a factor variable?