# NOT RUN {
data("DutchSales")
plot(DutchSales)
## EACF tables (Franses 1998, p. 99)
ctrafo <- function(x) residuals(lm(x ~ factor(cycle(x))))
ddiff <- function(x) diff(diff(x, frequency(x)), 1)
eacf <- function(y, lag = 12) {
stopifnot(all(lag > 0))
if(length(lag) < 2) lag <- 1:lag
rval <- sapply(
list(y = y, dy = diff(y), cdy = ctrafo(diff(y)),
Dy = diff(y, frequency(y)), dDy = ddiff(y)),
function(x) acf(x, plot = FALSE, lag.max = max(lag))$acf[lag + 1])
rownames(rval) <- lag
return(rval)
}
## Franses (1998), Table 5.3
round(eacf(log(DutchSales), lag = c(1:18, 24, 36)), digits = 3)
# }
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