Howdy I apologize for duplicated posting. But I decided to correct my previous posting.
I had the regression results using r <- lm(Y ~ nemp + as.factor(devt), data=d). First, there is the result of anova(r). Here I could not find regression coefficients. Response: Y Df Sum Sq Mean Sq F value Pr(>F) nemp 1 58.2 58.2 1233.23 < 2e-16 *** as.factor(devt) 3 3.6 1.2 25.69 2.6e-16 *** Second, there is the result of summary(r) that I am confused with too many coefficients for a factor variable "devt". Because there are three coefficients for factor variables such as"as.factor(devt)A ", "as.factor(devt)B", "as.factor(devt)C". Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) as.factor(devt1) 3 3.6 1.2 25.69 2.6e-16 *** 5.95e-02 10.19 < 2e-16 *** nemp 2.87e-06 1.04e-07 27.63 < 2e-16 *** as.factor(devt)A 2.44e-02 1.47e-02 1.66 0.09630 . as.factor(devt)B -1.10e-01 1.40e-02 -7.90 4.6e-15 *** as.factor(devt)C -9.19e-03 1.53e-02 -0.60 0.54953 Is this model right as a tentative model at least? Y = 6.07e-01 + 2.87e-06* nemp + 2.44e-02 * as.factor(devt)A - 1.10e-01 * as.factor(devt1)B - 9.19e-03 * as.factor(devt)C And so, my question is "which coefficients should I use for a final model?". Thanks in advance, -- Kum-Hoe Hwang, Ph.D.Phone : 82-31-250-3516Email : [EMAIL PROTECTED] [[alternative HTML version deleted]] ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html