Performs Kolmogorov-Smirnov Goodness-of-Fit Test for Independent-Samples.

This procedure performs a two-sample Kolmogorov-Smirnov test to compare the distributions of values in two data sets. For each potential value x, the Kolmogorov-Smirnov test compares the proportion of values in the first sample less than x with the proportion of values in the second sample less than x. The null hypothesis is that the two samples have the same continuous distribution. The alternative hypothesis is that they have different continuous distributions.

Assumptions:

•samples are random

•two samples are mutually independent

•measurement scale is at least ordinal

•Samples in one column:

Choose if the sample data are in a single column, differentiated by factor levels in a second column.

oSamples: Enter the columns containing the sample data.

oFactor and Levels: Enter the columns containing the sample factor, and select the levels.

•Samples in different columns:

Choose if the data of the two samples are in separate columns.

oFirst Sample: Enter the column containing one sample.

oSecond Sample: Enter the column containing the other sample

•Report:

The display of outputs of VisualStat.

Data can be entered in one of two ways:

•Both samples in a single numeric column with another grouping column (called factor) to identify the population. The grouping column may be categorical, numeric or text.

•Each sample in a separate numeric column.

The sample sizes do not need to be equal. Missing values are ignored.

Displays a histogram, a histogram with a normal curve, and a boxplot.

•Histogram:

Choose to display a histogram for each variable

•Histogram with Normal Curve:

Choose to display a histogram with a normal curve for each variable

•Boxplot of data:

Choose to display a boxplot for each variable

•Options:

Choose the options you want.

oExclude missing values: Check to excludes rows that have missing values.

oInverted Bar: Check to reverse the axes.

Confidence Level: Enter the level of confidence desired. Enter any number between 0 and 100. Entering 90 will result in a 90% confidence interval. The default is 95%.

1.Open the DataBook nonparam.vstz

2.Select the sheet k2

3.Choose the tab Statistics, the group Nonparametric Tests and the command Two Kolmogorov

4.Select group Samples in different columns

5.In First Sample, select Process 1 (Old). In Second Sample, select Process 2 (New).

6.Click OK

Report window output

Two-sample Kolmogorov-Smirnov Test

Kolmogorov-Smirnov test to compare the distributions of values in two data sets

alternative hypothesis: true the two samples have different continuous distributions

N1 N2 Critical Value alpha ks p-value Alt Hypothesis

Process 1 (Old) : Process 2 (New) 11 9 0.5672 0.95 0.4545 0.1870 Reject

See Also: |