Message-ID: <91EF0870-5FCE-4960-8234-BF1A5CEC1072@gmail.com>
Date: 2014-01-21T19:11:49Z
From: Peter Dalgaard
Subject: how to get the numbers of factors in a matrix
In-Reply-To: <86c25d31-001a-4cc9-81f9-982a30a94866@email.android.com>
On 21 Jan 2014, at 15:58 , Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote:
> You are mis-using factors. Would you pretend that women do not exist just because your sample happens to include only men?
>
> If you really need to ignore those other levels, convert your factor to character and summarize those values.
Actually, just factor(fff) will do. Or droplevels(fff).
--
Peter Dalgaard, Professor
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Email: pd.mes at cbs.dk Priv: PDalgd at gmail.com