pcts (version 0.15.8)

pcalg1util: Give partial periodic autocorrelations or other partial prediction quantities for a pcAcvf object.

Description

Give partial periodic autocorrelations or other partial prediction quantities for a pcAcvf object.

Usage

alg1util(x, s, at0 = 1)

Value

the requested quantity as an object of type slMatrix

Arguments

x

an object of a class inheriting from pc.Model.WeaklyStat

s

the required quantity, the name of one of the elements of the list returned by alg1.

at0

if not identical to "var", replace the elements of the result at lag zero with 1, see `Details'.

Author

Georgi N. Boshnakov

Details

This function is a wrapper for alg1(). It calls alg1, to do the computations and returns the requested element as an object from class slMatrix. The model order is set to the maximal lag avialable in x,

If at0 is the character string "var", then the lag zero values in the result are set to the lag zero autocovariances, otherwise they are set to 1. This is mainly relevant for the periodic partial autocorrelations (s="be"), since the setting at0="var" ensures that they are in one to one correspondence with the autocovariances.

References

Lambert-Lacroix S (2000). ``On periodic autoregressive process estimation .'' IEEE Transactions on Signal Processing, 48( 6 ), pp. 1800-1803.

Lambert-Lacroix S (2005). `` Extension of autocovariance coefficients sequence for periodically correlated processes.'' Journal of Time Series Analysis, 26(6), pp. 423-435.

See Also

pdSafeParOrder, alg1

Examples

r1 <- rbind(c(1,0.81,0.729),c(1,0.90,0.900))

# example of Lambert-Lacroix
data(ex1f)
pc3 <- slMatrix(period=2,maxlag=5,f=ex1f,type="tt")
res0p2 <- alg1(pc3[],c(0,2))
res1p2 <- alg1(pc3[],c(1,2))
res3p3 <- alg1(pc3[],c(3,3))