This example illustrates the use of spectral analysis.
The following statements perform a spectral analysis on the SUNSPOT dataset. The periodogram is displayed as a function of the period and frequency in Output 32.4.1. The estimated spectral density together with its 50% confidence limits are displayed in Output 32.4.2.
title "Wolfer's Sunspot Data"; proc timeseries data=sunspot plot=(series periodogram spectrum); var wolfer; id year interval=year; spectra freq period p s / adjmean bart c=1.5 expon=0.2; run;