>From previous posting:
"This is my function:
wilcox.test(A,B, data = data, paired = FALSE)
It gives me high p value, though the median of A column is 6900 and B
column is 3500.
Why it gives p value high if there is a difference in the median?"
Let's examine your choice to use the Wilcoxon test with paired = FALSE.
If both A and B are given and paired is FALSE, a Wilcoxon rank sum test
(equivalent to the Mann-Whitney test) is carried out. In this case, the null
hypothesis is that the distributions of x and y differ by a location shift of mu
and the alternative is that they differ by some other location shift (and the
one-sided alternative "greater" is that A is shifted to the right of
B).
You observed that the medians are different. While the medians may be different,
the test is dependent on ranks not medians.
HTH,
Thomas Subia