##-------------------------------------------------------## ## An R Companion to Applied Regression, Second Edition ## ## Script for Appendix on Timeseries Regression ## ## ## ## John Fox and Sanford Weisberg ## ## Sage Publications, 2011 ## ##-------------------------------------------------------## library(car) Hartnagel[c(1:6, 36:38), ] plot(fconvict ~ year, type="n",data=Hartnagel, ylab="Convictions per 100,000 Women") grid(lty=1) with(Hartnagel, points(year, fconvict, type="o", pch=16)) mod.ols <- lm(fconvict ~ tfr + partic + degrees + mconvict, data=Hartnagel) summary(mod.ols) plot(Hartnagel$year, residuals(mod.ols), type="o", pch=16, xlab="Year", ylab="OLS Residuals") abline(h=0, lty=2) acf(residuals(mod.ols)) acf(residuals(mod.ols), type="partial") durbinWatsonTest(mod.ols, max.lag=5) library(lmtest) dwtest(mod.ols, alternative="two.sided") library(nlme) mod.gls <- gls(fconvict ~ tfr + partic + degrees + mconvict, data=Hartnagel, correlation=corARMA(p=2), method="ML") summary(mod.gls) mod.gls.3 <- update(mod.gls, correlation=corARMA(p=3)) mod.gls.1 <- update(mod.gls, correlation=corARMA(p=1)) mod.gls.0 <- update(mod.gls, correlation=NULL) anova(mod.gls, mod.gls.1) anova(mod.gls, mod.gls.0) anova(mod.gls.3, mod.gls)