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Learning Decision Trees using the Fourier Spectrum. By Eyal Kushilevitz Yishay Mansour. What is Learning. What are we Learning?. Term (and of literals (. DNF (or of terms). DT , : See latter. Does always. All inputs. We Want:. Randomized Algorithm. Do we always succeed ?.
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Learning Decision Treesusing the Fourier Spectrum By Eyal Kushilevitz Yishay Mansour Haim Kermany
What are we Learning? • Term (and of literals( • DNF (or of terms) • DT , : See latter
Does always All inputs We Want: Randomized Algorithm Do we always succeed ?
(1+ 1)mod 2=0 Fourier Transform
t-phase function – a function that has at most t Fourier coefficient t-phase function Only big coefficients Very small
Tree What we need
Approximating chernoff
Changing coef() Save Side
chernoff Finding
There will be coefficients Running time is Coaf() time
Finding chernoff
Can be exp(n) Best algorithm ever
+1 -1 -1 -1 -1 -1 +1 +1 +1 +1 +1 Decision Tree (DT)
Decision Tree (DT) Proof:
choose: Exacting