# SOCR EduMaterials AnalysisActivities KolmogorovSmirnoff

(Difference between revisions)
 Revision as of 07:05, 17 October 2008 (view source)Annie (Talk | contribs) (New page: == SOCR Analyses Example on Kolmogorov-Smirnoff Test. == This example is based on a dataset from the '''R package''' under the library '''MASS'''. The dataset's name is '''oats'''. The ...)← Older edit Revision as of 19:33, 20 October 2008 (view source)IvoDinov (Talk | contribs) Newer edit → Line 1: Line 1: - == SOCR Analyses Example on Kolmogorov-Smirnoff Test. == + == [[SOCR_EduMaterials_AnalysisActivities | SOCR Analysis Activities]] - SOCR Analyses Example on Kolmogorov-Smirnoff Test== - This example is based on a dataset from the '''R package''' under the library '''MASS'''. The dataset's name is '''oats'''. + ===Overview of the Kolmogorov-Smirnoff Test=== + The Kolmogorov-Smirnoff test (KS-test) compares how distinct two datasets are. The KS-test has makes no assumption about the distribution of data, and therefore is a [http://en.wikipedia.org/wiki/Non-parametric_statistics non-parametric, or distribution-free, test]. Other [http://en.wikipedia.org/wiki/Parametric_statistics parametric tests], e.g., Student's t-test, Normal Z-test, etc., may be more [[AP_Statistics_Curriculum_2007_Hypothesis_Basics#Type_I_Error.2C_Type_II_Error_and_Power | sensitive] if the ''data meet the requirements'' of the test. - The quantitative variable '''Y''' (yields of oats field) is grouped by three varieties (the categorical varible here), '''Victory''', '''Golden.rain''' and '''Marvellous'''. + ===Examples== + 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 analysis steps: + ====The analysis steps==== - '''1.''' As you start the SOCR Analyes 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. + * As you start the [http://www.socr.ucla.edu/htmls/SOCR_Analyses.html 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.
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig1.gif|700px]]
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig1.gif|700px]]
- + * Click on the '''Mapping''' tab to map the groups you would like to include in the analysis. Select two groups. - '''2.''' Click on the '''Mapping''' tab to map the groups you would like to include in the analysis. Select two groups. +
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig2.gif|700px]]
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig2.gif|700px]]
- + * Now you will click on '''Compute''' to let the program produce the results. Click on '''Result''' to view the results. - '''3.''' Now you will click on '''Compute''' to let the program produce the results. Click on '''Result''' to view the results. +
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig3.gif|700px]]
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig3.gif|700px]]
- '''4.''' Click on Graph to view plots. + * Click on Graph to view plots.
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig4.gif|700px]]
[[Image:SOCR_AnalysisActivities_Survival_Chu_081015_KSFig4.gif|700px]]
- '''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. + : '''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.

- {{translate|pageName=http://wiki.stat.ucla.edu/socr/index.php?title=SOCR_EduMaterials_AnalysisActivities_Survival}} + {{translate|pageName=http://wiki.stat.ucla.edu/socr/index.php?title=SOCR_EduMaterials_AnalysisActivities_KolmogorovSmirnoff}}

## 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 has makes no assumption 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 [[AP_Statistics_Curriculum_2007_Hypothesis_Basics#Type_I_Error.2C_Type_II_Error_and_Power | sensitive] if the data meet the requirements of the test.

## =Examples

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 analysis steps

• 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.