Time series


GenStat provides several methods for examining and analysing time series. Sample correlation functions are produced by the directive CORRELATE:


CORRELATE
forms correlations between variates, autocorrelations of variates, and lagged cross-correlations between variates


The analysis of Box-Jenkins models is specified by several directives:


FTSM
forms preliminary estimates of parameters in time-series models

TRANSFERFUNCTION
specifies input series and transfer-function models for subsequent estimation of a model for an output series

ESTIMATE
estimates parameters in Box-Jenkins models for time series


Information can be saved in GenStat data structures, or further output can be produced:


TDISPLAY
displays further output after an analysis by ESTIMATE

TKEEP
saves results after an analysis by ESTIMATE

FORECAST
forecasts future values of a time series

TSUMMARIZE
displays characteristics of a time series model


It is also possible to filter a time series, or perform spectral analysis via the Fourier transform of a time series using the directives:


FILTER
filters time series by time-series models

FOURIER
calculates cosine or Fourier transforms of a real or complex series


Procedures in module timeseries of the Library include:


BJESTIMATE
fits an ARIMA model, with forecasts and residual checks

BJFORECAST
plots forecasts of a time series using a previously fitted ARIMA

BJIDENTIFY
displays time series statistics useful for ARIMA model selection

PERIODTEST
gives periodogram-based tests for white noise in time series

PREWHITEN
filters a time series before spectral analysis

REPPERIODOGRAM
gives periodogram-based analyses for replicated time series

SMOOTHSPECTRUM
forms smoothed spectrum estimates for univariate time series