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Using Aids2 dataset from package MASS, I am applying Ansari-Bradley Non-Parametric Test to test Group Independency by this snippets

library(coin)
library(MASS)
a1 <- ansari_test(Aids2$diag~Aids2$state)
a2 <- ansari_test(Aids2$diag~Aids2$sex)

if I take a peek of a1 and a2 object it gives summary like this:

Asymptotic K-Sample Ansari-Bradley Test

data:  Aids2$diag by Aids2$state (NSW, Other, QLD, VIC)
chi-squared = 4.4829, df = 3, p-value = 0.2138

Asymptotic Two-Sample Ansari-Bradley Test

data:  Aids2$diag by Aids2$sex (F, M)
Z = -1.6765, p-value = 0.09364
alternative hypothesis: true ratio of scales is not equal to 1

with the respective object class is:

> class(a1)
[1] "QuadTypeIndependenceTest"
attr(,"package")
[1] "coin"
> class(a2)
[1] "ScalarIndependenceTest"
attr(,"package")
[1] "coin"

However since I am only interested to the p-value (p-value = 0.2138), I would like only to extract that from the object, but I couldnt find how to extract it..

Jovan
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1 Answers1

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Since object like "QuadTypeIndependenceTest" and "ScalarIndependenceTest" are created from the results of coin packages, there is specific function to extract the pvalue, using coin::pvalue(obj), Special thanks for pointing @AntoniosK

Jovan
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