# NOT RUN {
## load and transform data
## (DAL: Delta Air Lines, LU: Lucent Technologies)
data("SP2001")
stock.prices <- SP2001[, c("DAL", "LU")]
stock.returns <- diff(log(stock.prices))
## price and return series
plot(stock.prices, ylab = c("Delta Air Lines", "Lucent Technologies"), main = "")
plot(stock.returns, ylab = c("Delta Air Lines", "Lucent Technologies"), main = "")
## monitoring of DAL series
myborder <- function(k) 1.939*k/28
x <- as.vector(stock.returns[, "DAL"][1:28])
dal.cusum <- mefp(x ~ 1, type = "OLS-CUSUM", border = myborder)
dal.mosum <- mefp(x ~ 1, type = "OLS-MOSUM", h = 0.5, period = 4)
x <- as.vector(stock.returns[, "DAL"])
dal.cusum <- monitor(dal.cusum)
dal.mosum <- monitor(dal.mosum)
## monitoring of LU series
x <- as.vector(stock.returns[, "LU"][1:28])
lu.cusum <- mefp(x ~ 1, type = "OLS-CUSUM", border = myborder)
lu.mosum <- mefp(x ~ 1, type = "OLS-MOSUM", h = 0.5, period = 4)
x <- as.vector(stock.returns[, "LU"])
lu.cusum <- monitor(lu.cusum)
lu.mosum <- monitor(lu.mosum)
## pretty plotting
## (needs some work because lm() does not keep "zoo" attributes)
cus.bound <- zoo(c(rep(NA, 27), myborder(28:102)), index(stock.returns))
mos.bound <- as.vector(boundary(dal.mosum))
mos.bound <- zoo(c(rep(NA, 27), mos.bound[1], mos.bound), index(stock.returns))
## Lucent Technologies: CUSUM test
plot(zoo(c(lu.cusum$efpprocess, lu.cusum$process), index(stock.prices)),
ylim = c(-1, 1) * coredata(cus.bound)[102], xlab = "Time", ylab = "empirical fluctuation process")
abline(0, 0)
abline(v = as.Date("2001-09-10"), lty = 2)
lines(cus.bound, col = 2)
lines(-cus.bound, col = 2)
## Lucent Technologies: MOSUM test
plot(zoo(c(lu.mosum$efpprocess, lu.mosum$process), index(stock.prices)[-(1:14)]),
ylim = c(-1, 1) * coredata(mos.bound)[102], xlab = "Time", ylab = "empirical fluctuation process")
abline(0, 0)
abline(v = as.Date("2001-09-10"), lty = 2)
lines(mos.bound, col = 2)
lines(-mos.bound, col = 2)
## Delta Air Lines: CUSUM test
plot(zoo(c(dal.cusum$efpprocess, dal.cusum$process), index(stock.prices)),
ylim = c(-1, 1) * coredata(cus.bound)[102], xlab = "Time", ylab = "empirical fluctuation process")
abline(0, 0)
abline(v = as.Date("2001-09-10"), lty = 2)
lines(cus.bound, col = 2)
lines(-cus.bound, col = 2)
## Delta Air Lines: MOSUM test
plot(zoo(c(dal.mosum$efpprocess, dal.mosum$process), index(stock.prices)[-(1:14)]),
ylim = range(dal.mosum$process), xlab = "Time", ylab = "empirical fluctuation process")
abline(0, 0)
abline(v = as.Date("2001-09-10"), lty = 2)
lines(mos.bound, col = 2)
lines(-mos.bound, col = 2)
# }
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