Re: st: interpretation of squared term

[David Bai <db555@mail.com>]

Thank you, Maarten.

I include the squared term because this year variable might be 
non-linearly related to the outcome. Is there an easier way to roughly 
interpret the year effect? I do not want to go deeper to have an exact 
interpretation of the two year variables. E.g., what does a negative 
coefficient for a squared term mean? Thank you.

-----Original Message-----
From: Maarten buis <maartenbuis@yahoo.co.uk>
To: statalist@hsphsun2.harvard.edu
Sent: Thu, Aug 26, 2010 3:28 pm
Subject: Re: st: interpretation of squared term


--- On Thu, 26/8/10, David Bai <db555@mail.com> wrote:
>   I have a question regarding how to interpret squared
> term:
You can only interpret the time trend graphically. If you
want to have a non-linear trend where you can interpret
the coeficients, you can look at a linear spline, see
-help mkspline-.

Hope this helps,
Maarten

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

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




*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/

 

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/