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Is it possible for decision trees to split a set of data into
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Is it possible for decision trees to split a set of data into subsets where the sum of the entropies (weighted respectively) of each subset will be greater than the original entropy of the set?

I know its a bit contrived, but can there be a scenario where I would need to worry about negative information gain?

Or will this not be a problem and all I have to do is plug and chug and only minimize entropy after, without worrying about its relationship to entropy before?

>inb4 goto /g/, /g/ cant even into entropy apparently
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bump
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>>7757093
stop bumping your shitty thread
where did you learn about entropy that allows negative information gain?
where did you learn about entropy or information gain that causes you to ask
>Is it possible for decision trees to split a set of data into subsets where the sum of the entropies (weighted respectively) of each subset will be greater than the original entropy of the set?

are you in an online degree from some third-world porta-potty? or are you trying to convince some random company that you don't need a degree to be a data miner?
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just a student thats having a bit of trouble with yesterdays material, jesus christ

let x = {0,0,0,1,1,1}
is there a y that is a subset of x such that the entropy is greater in y
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>>7757142
please just open a textbook wow
literally every subset of x has a higher entropy than x
>shitposting homework on sci that you haven't even looked at other than to copy into a post
shiggy diggy sage
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>>7757142
Anon, a set of determined digits has 0 entropy...
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>>7757093
That is not really how information entropy works. Its used more as a guide to building the tree.
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k let me rephrase my dumbass self.

decision trees are known to select splitting attributes via maximizing information gain/minimizing the entropy of any one attribute as a decision applied over some set X.

I am asking if the algorithm would ever need to consider attributes that were retarded or contrived so that the information gain was negative (SOMEHOW) or would we instead have to worry about it and have to do something like max(x, 0) to prevent bullshit "malicious" attributes
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>>7757170
it is implied that with a set you calculate entropy assuming you choose random objects from the set, kid...
so {1, 1, 1, 1} has entropy of -(4/4)*log_2(4/4) and {1, 1, 0, 0} has entropy of -((2/4)*log_2(2/4) + (2/4)*log_2(2/4))
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>>7757183
Textbook, seriously.

Hell, just look at the equation for entropy! If you can't deduce it from that then what are you doing in university?
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>>7757187
perhaps I am unsure of my mathematics and just need a little help because I am human and am still learning, and you are not contributing and to me feel like an academic elitist

>just maybe
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>>7757191
or perhaps you're lazy
or maybe retarded
neither of which should be shitposting on sci
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>>7757187
also my question said over all subsets in every possible weight.

so its not so simple as hurr durr 0 <= x <= 1
its the sum of the weighted entropy by number of elements within in each subset w/ respect to the original set
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>>7757205
actually, I just dont think you understand the gravity of my question
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