The method I saw that's generally used to deal with large # of nominal variables is to keep the most frequent variables and introduce a new "other" category. But that's not possible with my data with equal # of tuples for each nominal variable. How do I handle this? I have 70 tuples for each of the 250 categories.
Edit: After researching more, I think I should use target encoding with prior smoothing but could someone suggest an appropriate value for the smoothing parameter in python?