Re: st: Including constant?

[Maarten Buis <maartenlbuis@gmail.com>]

--- At 07:23 AM 6/1/2011, lreine ycenna wrote:
>>>Do we typically not have to include constants in regression tables
>>>when presenting them?

 --- Richard Williams wrote:
>> But, I personally always include them. It is particularly useful if
>> somebody wants to calculate a yhat value for some combination of
>> values for the Xs.

---- On Wed, Jun 1, 2011 at 6:28 PM, Nick Cox wrote:
> In various Earth and environmental sciences in which I write or
> review papers leaving out the constant would be generally
> regarded as gross statistical illiteracy.

Adding and discussing the constant term (after appropriately centering
your explanatory/independent/right hand side/x variables) can be
useful for refreshing the memory of your readers on what the unit of
your explained/dependent/left hand side/y variable is. This can be
particularly useful in models like logistic regression, where the unit
is the odds of "success". Refreshing/explaining what an odds is is
often necessary or at least useful. See for example:
http://www.stata.com/statalist/archive/2011-02/msg00785.html

-- Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------
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