27.03.2013 Views

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

1090 NPAR TESTS<br />

Example<br />

• A test statistic is calculated for each variable specified.<br />

NPAR TESTS K-S(UNIFORM)=V1 /K-S(NORMAL,0,1)=V2.<br />

• The first K-S subcommand compares the distribution of V1 with a uniform distribution<br />

that has the same range as V1.<br />

• The second K-S subcommand compares the distribution of V2 with a normal distribution<br />

that has a mean of 0 and a standard deviation of 1.<br />

K-S Subcommand (Two-Sample)<br />

<strong>Syntax</strong><br />

Operations<br />

Example<br />

NPAR TESTS K-S=varlist BY variable(value1,value2)<br />

K-S (alias KOLMOGOROV-SMIRNOV) tests whether the distribution of a variable is the same<br />

in two independent samples defined by a grouping variable. The test is sensitive to any<br />

difference in median, dispersion, skewness, and so forth, between the two distributions. The<br />

output shows the valid number of cases in each group in the Frequency table and the largest<br />

absolute, positive, and negative differences between the two groups, the Kolmogorov-<br />

Smirnov Z, and the two-tailed probability for each variable in the Test Statistics table.<br />

• The minimum specification is a test variable, the keyword BY, a grouping variable, and a<br />

pair of values in parentheses.<br />

• The test variable should be at least at the ordinal level of measurement.<br />

• Cases with the first value form one group and cases with the second value form the other.<br />

The order in which values are specified determines which difference is the largest positive<br />

and which is the largest negative.<br />

• The observed cumulative distributions for both groups are computed, as are the maximum<br />

positive, negative, and absolute differences. A test statistic is calculated for each variable<br />

named before BY.<br />

• Cases with values other than those specified for the grouping variable are excluded.<br />

NPAR TESTS K-S=V1 V2 BY V3(0,1).<br />

• This example specifies two tests. The first compares the distribution of V1 for cases with<br />

value 0 for V3 with the distribution of V1 for cases with value 1 for V3.<br />

• A parallel test is calculated for V2.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!