How can I change the significance level of either kruskalwallis or ranksum test?

Hi, this is probably an easy question for rehular matlab users but leaves me standing infront of a problem: the default significance level of kruskalwallis is 0.01 and the obe for ranksum 0.05...I would like to use the same for both and found that you can change it just not "how". Where in the code do you put the alpha value in?

I typed it in like you would for a t-test but that should change the p-value depending on your significance level i.e. if the null hypothesis gets just about accepted with 0.05 it should be rejected with 0.01. However, the p-value remains the same in both cases...

Thanks!

Answer 1

[Star Strider]

For ranksum, you have to specify it as a name-value pair as 'alpha' (link).

The kruskalwallis doesn’t have that option. However, it outputs the p-value, so you can use it to make your own decisions.

[Fiona Schulz]

But a difference in alpha for the ranksum test should change the p-value, right?

With the default setting of 0.05, I get p=0.0614

If I change to 'alpha',0.01, I get p=0.0614

[Star Strider]

It will not change the p-value. It only affects the second output (in the documentation, logical value ‘h’), that is the ‘test decision flag’.