Felipe Carrillo <mazatlanmexico <at> yahoo.com> writes: ## snip
In the absence of any other information, I would say your best bet would just be to take the weekly average across the previous years. There are lots of ways to do this (tapply, aggregate, etc.), but cast() works: fallavg <- cast(fallmelt,value="value",WEEK~.,fun.aggregate=mean, na.rm=TRUE) names(fallavg)[2] <- "value" fallavg$variable <- "predicted" ggplot(fallmelt,aes(WEEK,value/1000,linetype=variable, colour=variable,fill=variable)) + geom_line(size=1)+ theme_bw() + scale_x_continuous(breaks=seq(1,52,3), labels=levels(fall$week)[seq(1,52,3)],) + opts(title="Fall Cumulative") + labs(y="Number of fish X 1,000",x="WEEK")+ geom_line(data=fallavg,size=2) ______________________________________________ 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.