/* SAS code for performing McNemar's test for    */
/* analyzing 2 by 2 table:                       */
/* Comparing two proportions with paired samples.*/

/* We analyze the ice cream data from class:     */

DATA icecream;
INPUT namebrand $ economy $ number;
cards;
like like 38
like dislike 92
dislike like 13
dislike dislike 57
;
run;

/* In the TABLES statement below, the first variable listed is the row variable */
/* and the second variable listed is the column variable.                       */

PROC FREQ DATA = icecream ORDER=DATA;
TABLES namebrand*economy / agree;
WEIGHT number;
run;

/* SAS does not print the CI for pi_1 - pi_2, but the two-sided P-value for testing   */
/* H0: pi_1 = pi_2 is given (less than .0001) in the "McNemar" section of the output. */

/* ****************************************************************************** */