IMPORTANT: Error in project

The code for handling missing values in ex 1a) was not correct. Here is an alternative code (which also is included in an updated version of the project file)

fit = lm(logPM10~A+UTMX+UTMY+WS+TEMP+HMIX+PREC+EMI,data=d)
res = rep(NA,nrow(d))
res[!is.na(d$logPM10)] = resid(fit)
acf(res[d$Station==1],na.action=na.pass)
 

Note: If you already have done it with the commands given, you will not be punished for this.