Hi, On Mon, Nov 8, 2010 at 2:25 PM, Alan Chalk <alan.ch...@gcc.rsagroup.com> wrote: > Regarding unusual combinations of factors in categorical data.
where all variables are categorical? > Are there any R packages that can be used to identify the outliers i.e. > unusual combinations in categorical datasets ? "outlier" or "unusual" tends to be rather variable, that is something unusual in one data set may not be in another. If you are dealing with strictly categorical variables, I am not certain how you would define an outlier. The categories only have the meaning attached to them, so it seems like they would only indicate outliers if you decided that an entire category was an outlier (e.g., males, females, half-man-half-ox). If you have one continuous variable in mind by different levels of a factor, then you could just use some simple plots (e.g., ggplot() + geom_point() + facet_grid(factor ~ .) or something similar). You could also z-score the values by each factor level and then extract zscores more extreme than +/- 3 or whatever value you like. It might be easier to give you feedback if you have a more specific example. Cheers, Josh > > Thanks. > > > ================================================================================ > > Notice of Confidentiality > > This transmission contains information that may be confidential and that may > also be privileged. Unless you are the intended recipient of the message (or > authorised to receive it for the intended recipient) you may not copy, > forward, or otherwise use it, or disclose it or its contents to anyone else. > If you have received this transmission in error please notify us immediately > and delete it from your system. > > RSA Insurance Group plc. Registered in England No. 2339826. The Registered > Office is 9th Floor, One Plantation Place, 30 Fenchurch Street, London EC3M > 3BD > > ================================================================================ > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles http://www.joshuawiley.com/ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.