Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
From | Richard Williams <richardwilliams.ndu@gmail.com> |
To | statalist@hsphsun2.harvard.edu, statalist@hsphsun2.harvard.edu |
Subject | Re: st: Interaction with Squared Term |
Date | Tue, 25 Oct 2011 17:10:19 -0500 |
At 01:48 PM 10/25/2011, Ryan Goodstein wrote:
Hello, I am trying to estimate a multinomial logit specification that includes a categorical variable interacted with a squared term. Specifically: > mlogit dq60 invPS##c.o_ltv##c.o_ltv ageq ageq2 Stata (v11) gives me the following error: > invalid interaction specification; >> multiple 'o' operators attached to a single variable are not allowed within an> interaction specification{p_end} I saw a post on this on Stata List from 2009 which says this bug will be fixed in an update (http://www.stata.com/statalist/archive/2009-10/msg00584.html), but I haven't been able to find an update. Has this bug been fixed?
I assume you actually updated your Stata. If so, the comment about "o operators" makes me wonder if Stata is getting confused by your variable names. Try creating a clone of o_ltv (e.g. ltvo) and see if the problem persists.
------------------------------------------- Richard Williams, Notre Dame Dept of Sociology OFFICE: (574)631-6668, (574)631-6463 HOME: (574)289-5227 EMAIL: Richard.A.Williams.5@ND.Edu WWW: http://www.nd.edu/~rwilliam * * 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/