The Sashelp.ENSO
(El Niño–Southern Oscillation) data set contains measurements of monthly averaged atmospheric pressure differences between
Easter Island and Darwin, Australia, for a period of 168 months (National Institute of Standards and Technology 1998). These pressure differences drive the southern trade winds. This data set is used to illustrate fitting nonlinear functions
to a scatter plot by using methods such as loess and penalized B-splines. These data show both seasonal variations and variations
due to El Niño. The following steps display information about the Sashelp.ENSO
data set and create Figure B.9:
title 'El Nino Southern Oscillation Data'; proc contents data=sashelp.ENSO varnum; ods select position; run; title 'The First Five Observations Out of 168'; proc print data=sashelp.ENSO(obs=5); run;
Figure B.9: El Niño–Southern Oscillation Data