StatsWheelerWatsonTest
StatsWheelerWatsonTest [/ALPH=val /Q/Z/T=k /WSTR=waveListString ] [srcWave1, srcWave2, srcWave3,...]
The StatsWheelerWatsonTest operation performs the nonparametric Wheeler-Watson test for two or more samples. Output is to the W_WheelerWatson wave in the current data folder or optionally to a table.
Flags
| /ALPH = val | Sets the significance level (default val =0.05). | ||||||
| /DEST = wwWave | Specify the destination wave for the nonparametric Wheeler-Watson test results. If you do not use this flag, the operation saves this output in the wave W_WheelerWatson in the current data folder. | ||||||
| This flag was added in Igor Pro 10.00. | |||||||
| /FREE | Creates the user-specified destination wave as a free wave. | ||||||
| /FREE is allowed only in functions, and only if the destination waves are simple names or wave reference structure fields. | |||||||
| See Free Waves for more discussion. | |||||||
| The /FREE flag was added in Igor Pro 10.00. | |||||||
| /Q | No results printed in the history area. | ||||||
| /T = k | Displays results in a table. k specifies the table behavior when it is closed. | ||||||
| |||||||
| The table is associated with the test, not the data. If you repeat the test, it will update any existing table with the new results. | |||||||
| /WSTR = waveListString | |||||||
| Specifies a string containing a semicolon-separated list of waves that contain sample data. Use waveListString instead of listing each wave after the flags. | |||||||
| /Z | Ignores errors. V_flag will be set to -1 for any error and to zero otherwise. | ||||||
Details
The StatsWatsonWilliamsTest must have at least two input waves, which contain angles in radians (mod 2π), can be single or double precision, and can be of any dimensionality; the waves must not contain any NaNs or INFs.
The Wheeler-Watson H0 postulates that the samples came from the same population. The extension of the test to more than two samples is due to Mardia. The Wheeler-Watson test is not valid for data with ties, in which case you should use Watson's U2 test.
V_flag will be set to -1 for any error and to zero otherwise.
References
Mardia, K.V., Statistics of Directional Data, Academic Press, New York, New York, 1972.
See, in particular, Chapter 27 of:
Zar, J.H., Biostatistical Analysis, 4th ed., 929 pp., Prentice Hall, Englewood Cliffs, New Jersey, 1999.
See Also
Statistical Analysis, StatsWatsonUSquaredTest, StatsWheelerWatsonTest