[R] results of fligner.test

From: Stefan Th. Gries <stgries_at_gmail.com>
Date: Wed, 28 May 2008 20:43:06 -0700


Hi all

I have a question regarding the Fligner-Killeen test. I am using

I have a vector LENGTH and a factor RELATION that are distributed like this:

> table(LENGTH, RELATION)

      RELATION
LENGTH object subject

    1       9      51
    2      25      18
    3      36      23
    4      23      14
    5      17      13
    6      12       7
    7      10       5
    8       3       7
    9       4       3
    10      3       5
    11      4       2
    12      2       0
    13      0       2
    16      2       1
    22      0       1
    49      1       0
    53      1       0

I wanted to run a Fligner test to see whether the lengths for the two relations differ in terms of their variance. This is what I found, though:

#########
> fligner.test(LENGTH[RELATION=="subject"], LENGTH[RELATION=="object"])

        Fligner-Killeen test of homogeneity of variances data: LENGTH[RELATION == "subject"] and LENGTH[RELATION == "object"] Fligner-Killeen:med chi-squared = 18.3552, df = 14, p-value = 0.1911

> fligner.test(LENGTH[RELATION=="object"], LENGTH[RELATION=="subject"])

        Fligner-Killeen test of homogeneity of variances data: LENGTH[RELATION == "object"] and LENGTH[RELATION == "subject"] Fligner-Killeen:med chi-squared = 16.8838, df = 13, p-value = 0.2047

> fligner.test(LENGTH~RELATION)

        Fligner-Killeen test of homogeneity of variances data: LENGTH by RELATION
Fligner-Killeen:med chi-squared = 0.626, df = 1, p-value = 0.4288 #########

The order of the vectors etc. changes the results??? Needless to say this does not happen with var.test or ... Is this normal; if so, which one is the one to report?
Thanks,
STG



R-help_at_r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Received on Thu 29 May 2008 - 07:09:13 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Thu 29 May 2008 - 07:30:42 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.

list of date sections of archive