# Dimension Reduction - Which feature should remove to reduce the dimension of the matrix

Let's suppose that we have the following 2 tables:

If we want to reduce the dimension by one(in every table) which feature we should remove and why ?

I am confused about the way that i should work generally in this type of problems.

• For the left table i thought to check the combinations per 2 features and after i do this i understand that i should remove the x2 , because if i remove the x1 then (0,0) gives the value y = 0 or (y = 1) that means that we need another one feature to understand the value of y -- The same and with x3.It seems like underfeeting .For the right table the x1 characteristic i thought that have some noise in the data and for this reason the values of x1 is so far from y. So i choose to remove x1. Could someone answer to me if my work in this -particular- problem was correct and if not why ? – Emily Serone Jun 16 at 21:26