Example 28.5: Creating an Output Data Set Containing ChiSquare Statistics
This example uses the Color data from Example 28.1
to output the Pearson chisquare and the likelihoodratio
chisquare statistics to a SAS data set. The following
statements create a twoway table of eye color versus hair
color.
proc freq data=Color order=data;
weight Count;
tables Eyes*Hair / chisq expected cellchi2 norow nocol;
output out=ChiSqData pchi lrchi n nmiss;
title 'ChiSquare Tests for 3 by 5 Table of Eye and Hair Color';
run;
proc print data=ChiSqData noobs;
title 'ChiSquare Statistics for Eye and Hair Color';
title2 'Output Data Set from the FREQ Procedure';
run;
The CHISQ option produces chisquare tests, the
EXPECTED option displays expected cell frequencies in the
table, and the CELLCHI2 option displays the cell
contribution to the chisquare. The NOROW and NOCOL options
suppress the display of row and column percents in the
table.
The OUTPUT statement creates the ChiSqData data set with
eight variables: the N option stores the number of
nonmissing observations, the NMISS option stores the
number of missing observations, and the PCHI and LRCHI options
store Pearson and likelihoodratio chisquare statistics,
respectively, together with their degrees of freedom and
pvalues.
The preceding statements produce Output 28.5.1 through
Output 28.5.2.
Output 28.5.1: Contingency Table
ChiSquare Tests for 3 by 5 Table of Eye and Hair Color 
Frequency Expected Cell ChiSquare Percent 

Table of Eyes by Hair 
Eyes(Eye Color 
Hair(Hair Color) 
Total 
fair 
red 
medium 
dark 
black 
blue 
69 66.425 0.0998 9.06 
28 32.921 0.7357 3.67 
68 63.22 0.3613 8.92 
51 53.024 0.0772 6.69 
6 6.4094 0.0262 0.79 
222 29.13 
green 
69 59.543 1.5019 9.06 
38 29.51 2.4422 4.99 
55 56.671 0.0492 7.22 
37 47.53 2.3329 4.86 
0 5.7454 5.7454 0.00 
199 26.12 
brown 
90 102.03 1.4187 11.81 
47 50.568 0.2518 6.17 
94 97.109 0.0995 12.34 
94 81.446 1.935 12.34 
16 9.8451 3.8478 2.10 
341 44.75 
Total 
228 29.92 
113 14.83 
217 28.48 
182 23.88 
22 2.89 
762 100.00 


Output 28.5.2: ChiSquare Statistics
ChiSquare Tests for 3 by 5 Table of Eye and Hair Color 
Statistics for Table of Eyes by Hair 
Statistic 
DF 
Value 
Prob 
ChiSquare 
8 
20.9248 
0.0073 
Likelihood Ratio ChiSquare 
8 
25.9733 
0.0011 
MantelHaenszel ChiSquare 
1 
3.7838 
0.0518 
Phi Coefficient 

0.1657 

Contingency Coefficient 

0.1635 

Cramer's V 

0.1172 


The contingency table in Output 28.5.1 displays eye and hair
color in the order in which they appear in the Color
data set. The Pearson chisquare statistic in Output 28.5.2
provides evidence of an association between eye and hair
color (p=0.0073).
The cell chisquare values show that most of
the association is due to more greeneyed children with fair
or red hair and fewer with dark or black hair. The
opposite occurs with the browneyed children.
Output 28.5.3: Output Data Set
ChiSquare Statistics for Eye and Hair Color 
Output Data Set from the FREQ Procedure 
N 
NMISS 
_PCHI_ 
DF_PCHI 
P_PCHI 
_LRCHI_ 
DF_LRCHI 
P_LRCHI 
762 
0 
20.9248 
8 
.007349898 
25.9733 
8 
.001061424 

The OUT= data set is displayed in Output 28.5.3. It
contains one observation with the sample size, the number of
missing values, and the chisquare statistics and
corresponding degrees of freedom and pvalues as in
Output 28.5.2.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.