MLS Course 2, Week 4, Exercise 4,

Course Q&A Machine Learning Specialization Advanced Learning Algorithms
1

Why does the value best_feature = -1 in the last exercise of week 4? When I set it to zero, it does not work

2

Hi! Can you share the error message that indicates that it does not work?

3

Screenshot 2022-08-12 152655
Screenshot 2022-08-12 1526551587×541 86.5 KB

But it works when I set it back to -1

4

Thanks for the screenshot. It is exactly as the Error message says, you need to return -1 as the best feature when the targets are all the same value, or equivalently saying, you need to return -1 when no feature will give us any information gain. Please consider this as a requirement.

To understand why setting that variable as -1 will give us the desired result, you need to read the code, then think about if we set it to 0, how can it return a -1 as desired?

Raymond

5

Oh now i get it. Thank you for the explanation

1 Like
6

You’re welcome @iliasu_Sal!