Need understanding

Course Q&A Machine Learning Specialization Advanced Learning Algorithms
1

in the example for week 4 I need help understanding HOW we get the answer:

H(0.5) - (5/10H(0.8) = 5/10H(0.2))

if someone could break it down for me I would be grateful. I keep going over the math and getting weird answers. If I have to substitute the (H) for something then multiply that would make sense but then what is (H)?

2

Please give a reference where you saw this in the course, such as a lecture title and time mark.

4

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I would just like to know how to do this math by hand please.

5

It appears to me that all the math is shown in the slide.

6

But half of .8 is .4 and half of .2 is .1 which would equal 1 subtract .5 is .5. What am I missing?

7

Hi @Johnny_3rd,

How to compute H(p)? This video is a good reference to that: Advanced Learning Algorithms > Week 4 > Measuring purity

Cheers,
Raymond