library(TSA)
data(electricity)
?electricity
plot(electricity)
abline(lm(electricity~time(electricity)))
hist(electricity)
par(mfrow=c(2,2))
hist(electricity)
hist(sqrt(electricity))
hist(log(electricity))
hist(1/(electricity))
res=BoxCox.ar(electricity) 
res 

# log transformation is approx the best transformation.

par(mfrow=c(1,1))
plot(log(electricity))
plot(diff(log(electricity)))
lm1=lm(diff(log(electricity))~1)
summary(lm1)
acf(rstudent(lm1))
acf(log(electricity),lag.max=60)
acf(aggregate(log(electricity),nfreq=1))
acf(cumsum(arima.sim(model=list(ma=-.82),n=1000)))
#