fdGPH {fracdiff} | R Documentation |
Estimate the fractional (or “memory”) parameter d in the ARFIMA(p,d,q) model by the method of Geweke and Porter-Hudak (GPH). The GPH estimator is based on the regression equation using the peridogram function as an estimate of the spectral density.
fdGPH(x, bandw.exp = 0.5)
x |
univariate time series |
bandw.exp |
the bandwidth used in the regression equation |
The function also provides the asymptotic standard deviation and the standard error deviation of the fractional estimator.
The bandwidth is
bw = trunc(n ^ bandw.exp)
, where 0 < bandw.exp < 1 and n is the sample size.
Default bandw.exp = 0.5
.
d |
GPH estimate |
sd.as |
asymptotic standard deviation |
sd.reg |
standard error deviation |
Valderio A. Reisen and Artur J. Lemonte
see those in fdSperio
.
memory.long <- fracdiff.sim(1500, d = 0.3) fdGPH(memory.long$series)