THE HONG KONG POLYTECHNIC UNIVERSITY, DEPARTMENT OF EIE
Lecture Notes of Machine Learning
Lecture 4 Logistic Regression
February 7, 2015
1 LOGISTIC REGRESSION
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h
θ
(x) =g (θ
T
x) =
1
1 +e
−θ
T
x
Ù¥§
g (z) =
1
1 +e
−z
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¦logistic ¼êꕵ
g
0
(z) =
1
(1 +e
−z
)
2
e
−z
=
1
(1 +e
−z
)
·
µ
1 −
1
(1 +e
−z
)
¶
=g (z)(1 −g (z))
1
- 1
- 2
- 3
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