Hi r-help-boun...@r-project.org napsal dne 16.12.2009 15:58:56:
> Hi, > I am trying to create a set of dummy variables to use within a multiple linear > regression and am unable to find the codes within the manuals. > > For example i have: > Price Weight Clarity > IF VVS1 VVS2 > 500 8 1 0 0 > 1000 5.2 0 0 1 > 864 3 0 1 0 > 340 2.6 0 0 1 > 90 0.5 1 0 0 > 450 2.3 0 1 0 > > Where price is dependent upon weight (single value in each observation) and > clarity (split into three levels, IF, VVS1, VVS2). > I am having trouble telling the program that clarity is a set of 3 dummy > variables and keep getting error messages, what is the correct way? Well, try to bribe it. Or ask what please it to break its resistance. Seriously. What is a structure of your data in R. ?str what commands did you use for regression I suppose lm(Price~Weight+IF+VVS1+VVS2, data=your.data) shall not complain if your.data is a data frame. Regards Petr > > Any helps is greatly appreciated. > Matthew > > ______________________________________________ > 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. ______________________________________________ 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.