Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

From |
fabio.zona@unibocconi.it |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: interaction graph |

Date |
Wed, 23 Feb 2011 11:07:39 +0100 (CET) |

Hi, In a 2-D graph, isn't it possible to "fix" the value of the continuos moderator at some values (i.e. creating a dummy variable, for instance for values below the first quatile and above the third quartile) and use regplot? I think I found interact long time ago on the internet, saying it was downlodable. I did not know it was not an official command. ----- Messaggio originale ----- Da: "Nick Cox" <njcoxstata@gmail.com> A: statalist@hsphsun2.harvard.edu Inviato: Mercoledì, 23 febbraio 2011 10:47:39 GMT +01:00 Amsterdam/Berlino/Berna/Roma/Stoccolma/Vienna Oggetto: Re: st: interaction graph I don't have a specific suggestion. Your model produces a prediction surface and although there are some user-written commands for 3-D graphics plotting the entire surface is a problem for which you are better off outside Stata. On the other hand, generating predictions for a few fixed values of your moderator might produce an adequate graph. -interact- is not an official command. It follows that you should explain where it comes from, as long and often requested on this list. Nick On Wed, Feb 23, 2011 at 9:34 AM, Fabio Zona <fabio.zona@unibocconi.it> wrote: > time ago you suggested to use > > regplot x, separate(dummy) > > to graph interaction effect between a continuous variable and a dummy variable. > > > However, what command should I use if I have > a) a quadratic form (i.e., x + x_square) > b) the moderator is a continous variable (not a dummy), and it is multiplied by both x and x-square ?? > > The stata command "interact" works only with linear (i.e. non quadratic) models * * 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/

**Follow-Ups**:**Re: st: interaction graph***From:*Nick Cox <njcoxstata@gmail.com>

- Prev by Date:
**st: RE: Hansen's overidentification test interpretation in xtivreg2** - Next by Date:
**Re: st: Multilevel longitudinal analysis with censored data** - Previous by thread:
**Re: st: interaction graph** - Next by thread:
**Re: st: interaction graph** - Index(es):