I want to present a report that highlights the variables with lowest information, to emphasize that some action must be taken by the department that controls our data source. I've applied Shannon Entropy to every categorical variable in my dataset, but the problem is that not all the variables have the same number of classes, making me think that direct comparisson would be wrong.
Is there a way to compare the entropy between variables with different number of classes? Which alternatives can I apply to overcome this problem? Maybe some adjusted entropy or another measure of variability within a factor.