discretization in weka

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discretization in weka

haseulingbambu
Hello,

I have a question about discretization in j48. In manual calculation we usually determine data into some groups (ex: high/medium/low). how does weka determine the groups' limit (especially if the data are all numeric) while the groups are not manually defined from the beginning?

Thanks in advance.
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Re: discretization in weka

Eibe Frank-2
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Take a look at Chapter 6 of our data mining book (https://www.cs.waikato.ac.nz/~ml/weka/book.html), for example.

C4.5 (J48 in WEKA) performs local discretisation of a numeric attribute into two intervals by finding the split point that maximises information gain (considering only the data at the node to be split).

Cheers,
Eibe

On 23/05/2020, at 1:19 AM, [hidden email] wrote:

Hello,

I have a question about discretization in j48. In manual calculation we usually determine data into some groups (ex: high/medium/low). how does weka determine the groups' limit (especially if the data are all numeric) while the groups are not manually defined from the beginning?

Thanks in advance.
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