# SOCR EduMaterials AnalysisActivities KolmogorovSmirnoff

## Contents

## SOCR Analysis Activities - SOCR Analyses Example on Kolmogorov-Smirnoff Test

### Overview of the Kolmogorov-Smirnoff Test

The Kolmogorov-Smirnoff test (KS-test) compares how distinct two datasets are. The KS-test makes no assumptions about the distribution of data, and therefore is a non-parametric, or distribution-free, test. Other parametric tests, e.g., Student's t-test, Normal Z-test, etc., may be more sensitive if the *data meet the requirements* of the test. More information about the Kolmogorov-Smirnoff Test is available here.

### Examples

#### Oats Example

Go to the SOCR Kolmogorov-Smirnoff Test Applet. This example is based on a dataset from the **R package** under the library **MASS**. The dataset's name is **oats**. The quantitative variable **Y** (yields of oats field) is grouped by three varieties (the categorical variable here), **Victory**, **Golden.rain** and **Marvelous**.

- The treatment structure in this experiment was a 3 × 4 full factorial, with 3 oat varieties and 4 nitrogen concentrations. The agricultural plots for this experiment were grouped into 6 blocks, each with 3 plots. Each plot was subdivided into 4 subplots. The varieties were randomly assigned to the plots within each block. The nitrogen concentrations were randomly assigned to the subplots within each plot. Physically, there are three levels of grouping of the experimental units: block, plot, and subplot. Because the treatments are randomly assigned at each level of grouping, we may be tempted to associate random effects with each level.

- As you start the SOCR Analyses Applet, click on
**Kolmogorov-Smirnoff Test**from the combo box in the left panel. Next, click on**Example 4**and then the**Data**tab on the top of the right panel. You will see something like below. The data have been divided into 6 columns by groups.

- Click on the
**Mapping**tab to map the groups you would like to include in the analysis. Select two groups.

- Now you will click on
**Compute**to let the program produce the results. Click on**Result**to view the results.

- Click on Graph to view plots.

**Note**: if you happen to click on the "Clear" button in the middle of the procedure, all the data will be cleared out. Simply start over from step 1.

#### Example 2: Control-Treatment test

#### Model fitting

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