This is a freeware (online ActiveX) program to perform nonparametric tests. It requires Internet Explorer 4 (Service Pack 2 or higher) or version 5 to operate.

What it does

1. Accepts data from the clipboard, e.g. data you copy from a spreadsheet. The data columns must contain the Block, Treatment, and Measurement. The first two may be alphanumeric. When there is no blocking, insert a dummy (e.g. "None") for the block. The measurement must be a real number.
2. Performs one of the following nonparametric tests:
• Kruskal-Wallis rank sum test (similar to one-way analysis of variance)
• Allows removal of block effects, e.g. if different product or material lots (blocks) are subjected to the treatments of interest. The Friedman test assumes one replicate of each treatment for each block; it does not (apparently) work when there are several replicates of each treatment for each block. This methodology- use of aligned observations, or observations whose block averages have been subtracted before ranking- is not yet proven or documented for the Kruskal-Wallis test. Use with caution.
• Also shows block ranks when blocking is present. If aligned ranks are used, there should be no block effects, i.e. no significant differences between the blocks.
• Friedman test for balanced complete block designs: each block or specimen gets one replicate of each treatment.
• Friedman test with aligned observation ranks. Aligned ranks are computed by (1) subtracting each block's average from each measurement in the block, thus removing block (specimen, lot) effects, and then (2) ranking the aligned observations against each other.
3. Shows the results.
• ActiveX page with the program
The program has been marked as safe for initialization and scripting. It writes a file called nonparam.txt to your hard drive; this is simply a copy of what you place on the clipboard. It does not write anything else to your hard drive unless you tell it to, e.g. to save a chart as a bitmap file.

Data Format for Input

This is how your data might look in a spreadsheet. Alphanumeric is O.K. for Block and Treatment. Copy your data (do not include the headers "Block," "Treatment," "Response") and click the appropriate button on the display. The tab character is the default column (field) separator, and it works for data that are copied from Excel spreadsheets. The program will read your data from the clipboard and perform the analysis.

Block	Treatment	Response
None	Group I	262
None	Group I	305
None	Group I	297
None	Group II	284
...	...	...

Testing

The program has been tested against examples in Wayne W. Daniel, 1990. Applied Nonparametric Statistics, 2nd ed. Boston: PWS-KENT Publishing Company.
• Example 6.2, Kruskal-Wallis test; reproduces book answer
• Problem 6.7, Kruskal-Wallis test; reproduces book answer
• Example 7.1, Friedman test; reproduces book answer
• Example 7.2, Friedman test with aligned ranks; reproduces book answer
• Problem 7.3, Friedman test; reproduces book answer for chi square (12.25). W corrected for ties is 0.8167. The text shows 0.766 (no correction for ties)


Note: This program's output does not constitute consulting engineering advice. Such advice can be provided only in person by an engineer who is registered to practice in your state.

ct-yankee_nonparam_index