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The SPECTRA Procedure |

**PROC SPECTRA***options;*

**A**-
outputs the amplitude variables (A_
*nn*_*mm*) of the cross-spectrum. **ADJMEAN****CENTER**-
subtracts the series mean before performing the Fourier decomposition.
This sets the first periodogram ordinate to 0 rather than 2
*n*times the squared mean. This option is commonly used when the periodograms are to be plotted to prevent a large first periodogram ordinate from distorting the scale of the plot. **ALTW**-
specifies that
the quadrature spectrum estimate is computed at the boundaries
in the same way as
the spectral density estimate and the cospectrum estimate are
computed.
**COEF**-
outputs the Fourier cosine and sine coefficients of each series,
in addition to the periodogram.
**CROSS**-
is used with the P and S options to output cross-periodograms
and cross-spectral densities.
**DATA=***SAS-data-set*-
names the SAS data set containing the input data.
If the DATA= option is omitted,
the most recently created SAS data set is used.
**K**-
outputs the squared coherency variables (K_
*nn*_*mm*) of the cross-spectrum. The K_*nn*_*mm*variables are identically 1 unless weights are given in the WEIGHTS statement and the S option is specified. **OUT=***SAS-data-set*-
names the output data set created by PROC SPECTRA to store the results.
If the OUT= option is omitted,
the output data set is named using the DATA
*n*convention. **P**-
outputs the periodogram variables.
The variables are named P_
*nn*, where*nn*is an index of the original variable with which the periodogram variable is associated. When both the P and CROSS options are specified, the cross-periodogram variables RP_*nn_mm*and IP_*nn_mm*are also output. **PH**-
outputs the phase variables (PH_
*nn*_*mm*) of the cross-spectrum. **S**-
outputs the spectral density estimates.
The variables are named S_
*nn*, where*nn*is an index of the original variable with which the estimate variable is associated. When both the S and CROSS options are specified, the cross-spectral variables CS_*nn*_*mm*and QS_*nn*_*mm*are also output. **WHITETEST**-
prints a test of the hypothesis that the series are white noise.
See "White Noise Test" later in this chapter for details.

Note that the CROSS, A, K, and PH options are only meaningful if more than one variable is listed in the VAR statement.

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