# LEfSe Galaxy Question

**URL:** <https://forum.biobakery.org/t/lefse-galaxy-question/1024>\
**Category:** LEfSe\
**Created:** [September 15, 2020, 11:14am UTC](https://forum.biobakery.org/t/lefse-galaxy-question/1024 "2020-09-15T11:14:34Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![abains1](https://yyz1.discourse-cdn.com/flex027/user_avatar/forum.biobakery.org/abains1/32/550_2.png) [@abains1](https://forum.biobakery.org/u/abains1)\
**Post date:** [September 15, 2020, 11:14am UTC](https://forum.biobakery.org/t/lefse-galaxy-question/1024/1 "2020-09-15T11:14:34Z")

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Hello,

I have seen a similar question asked before, but I am not entirely sure about the answer. I want to perform a LEfSe analysis, and the data I have does not contain a subclass. I am noticing that upon running LEfSe, I see the message “Number of significantly discriminative features: 0 ( 17 ) before internal wilcoxon.” However, this changes when I change the Alpha value for the wilcoxon test between subclasses from 0 to 1, and then I see significant features. I thought that the program would not perform a subclass wilcoxon test if there were no subclasses, and so that alpha value would not matter. My question is that if I do not want a subclass wilcoxon test to be performed, should I change the Alpha value to 1, so that there is no filtering based off subclass? Or does the program skip the wilcoxon test by default if I specified there were no subclasses in the previous step?

Thanks in advance!