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Topics Perceptron Exponential Family Generalized Linear Models Softmax Regression Multiclass Classification Logistic Regression a It g 2 z GG L 230 O Z CO hope 1 home g E'a It Ota 0 i O T x y how ng different y how 0 algo got it right L if wrong y L EEE y wrong y 0 Enzo Q O El i O O O

home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

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Page 1: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

TopicsPerceptronExponential FamilyGeneralized Linear Models

Softmax RegressionMulticlass Classification

Logistic Regressiona

It

g 2 z GG L 230O Z CO

hope 1home g E'aIt Ota

0 i O T x y how ngdifferent

y how0 algo got it rightL if wrong y L EEEy wrong y 0

EnzoQ

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O

Page 2: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

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Exponential FamiliesPDF

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n natural parameterTcg sufficient statistic

y in classblog Base measure

acq log partition function

y scalar

q vector scalar

TG vector scalar I match

b g scalar

ExampleBernoulli Binary Dataprobability of event

p g lo 494t y

exp log 994 09 exp y tog lo ta g logo a

exp log 9 t logo 0

Tks Fat

Page 3: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

bly ITcg gn log to q Csigmoid

acq logCto log l teenlog Iten

Gaussian w fixed variance or L

ply a En exp HIIe 5k expCpu y Zai

Tk Tk Tanbcg fan expC ETG yq µacne of IzProperties natural paramsMLE w r t 2 is concave

negative laglikelihood NLL is convex

EEg n a IqacnVarly y zigzag

Page 4: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

GLMAssumptions Design Clonolces

c yl K O Exponential familyReal GaussianBinary Bernoullicount PoissonRT Gamma ExponentialDist peta Dirichlet BayesianMystats

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Learning Update RulehoCa

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Page 5: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

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Classification

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Page 6: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

Softmax RegressionMulticlass Classification

Cross Entropy minimization

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Page 7: home g - Machine Learningcs229.stanford.edu/livenotes2020spring/cs229-livenotes... · 2020. 4. 16. · Multiclass Classification Cross Entropy minimization U2 g 00 O O 00 Lie K EIRD

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