Urgent :) Output interpretation: standard error of lm dummy variable
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On May 19, 2015 1:37:13 PM PDT, Livia Maria Vestergaard <lvest09 at student.sdu.dk> wrote:
Hi :) I have an an examination tomorrow, and don't quite understand how R calculated the values. Yes. You are right R^2=0.02166 :) As mentioned It is a dummy variable model with the 5 regions of Denmark as 4 independent dummy variables and price as the dependent variable. price = 10.325 - 0.176*Sjaeland - 0.368 * NJylland - 0.230*MJylland - 0.120* Syddanmark I will probably be asked how to interpret the standard error = 0.7348 on 342199 degrees of freedom (= 342 204 observations - 5 categories); about the 5 standard errors for the beta values, the F-statistic = 1894 on 4 categories and the p-value ? 0. But I don't quite understand how R reached the outputs and what parameter are F-distributed, what the standard errors says something about and the standard errors and the F-statistic = 1894 when it is a dummy variable model. Hopefully the answer is out there somewhere and you can help :) Best Livia
________________________________________ Fra: Livia Maria Vestergaard Sendt: 19. maj 2015 10:16 Til: r-help at r-project.org Emne: [R] Output interpretation: standard error of lm dummy variable Hi guys I have a statistical question to an analyse I ran in R. It is a dummy variable model with the 5 regions of Denmark as 4 independent dummy variables and price as the dependent variable: price = 10.325 - 0.176*Sjaeland - 0.368 * NJylland - 0.230*MJylland - 0.120* Syddanmark I understand the R^2 = 0.7348 - that it shows the explanatory force of the model (between 0 and 1) My question is simply how to interpret the standard error = 0.7348 on 342199 degrees of freedom? How is it calculated when the model is a dummy variable model. And what does it mean that the F-statistic says that there are 1894 on 4 and 342199 DF (degrees if freedom?) with a p-value < 0? I have been searching for hours - and can't quite figure out how R reached the numbers and how to interpret the output of standard error and the p-value of the dummy model. I really hope you can help :) Best Livia ------------------------------------------------------------------------ ______________________________________________ R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.