Slide 1

Slide 1 text

March 2016

Slide 2

Slide 2 text

Mainstream Media

Slide 3

Slide 3 text

1997

Slide 4

Slide 4 text

Ing cup 1985 – 2000 (up to 1,400,000$) (1985-2000)

Slide 5

Slide 5 text

5d win 1998

Slide 6

Slide 6 text

October 2015

Slide 7

Slide 7 text

This is the first time that a computer program has defeated a human professional player in the full-sized game of Go, a feat previously thought to be at least a decade away. Silver, D. et al., 2016. Mastering the game of Go with deep neural networks and tree search. Nature, 529(7587), p.484-489. January 2016

Slide 8

Slide 8 text

What did AlphaGo do to beat the strongest human Go player? Tobias Pfeiffer @PragTob pragtob.info

Slide 9

Slide 9 text

Go

Slide 10

Slide 10 text

Computational Challenge

Slide 11

Slide 11 text

Monte Carlo Method

Slide 12

Slide 12 text

Neural Networks

Slide 13

Slide 13 text

Revolution with Neural Networks

Slide 14

Slide 14 text

What did we learn?

Slide 15

Slide 15 text

Go

Slide 16

Slide 16 text

No content

Slide 17

Slide 17 text

No content

Slide 18

Slide 18 text

No content

Slide 19

Slide 19 text

No content

Slide 20

Slide 20 text

No content

Slide 21

Slide 21 text

No content

Slide 22

Slide 22 text

No content

Slide 23

Slide 23 text

No content

Slide 24

Slide 24 text

No content

Slide 25

Slide 25 text

No content

Slide 26

Slide 26 text

No content

Slide 27

Slide 27 text

No content

Slide 28

Slide 28 text

No content

Slide 29

Slide 29 text

No content

Slide 30

Slide 30 text

No content

Slide 31

Slide 31 text

No content

Slide 32

Slide 32 text

No content

Slide 33

Slide 33 text

No content

Slide 34

Slide 34 text

No content

Slide 35

Slide 35 text

Computational Challenge

Slide 36

Slide 36 text

Go vs. Chess

Slide 37

Slide 37 text

Complex vs. Complicated

Slide 38

Slide 38 text

„While the Baroque rules of chess could only have been created by humans, the rules of go are so elegant, organic, and rigorously logical that if intelligent life forms exist elsewhere in the universe, they almost certainly play go.“ Edward Lasker (chess grandmaster)

Slide 39

Slide 39 text

Larger board 19x19 vs. 8x8

Slide 40

Slide 40 text

Almost every move is legal

Slide 41

Slide 41 text

Average branching factor: 250 vs 35

Slide 42

Slide 42 text

State Space Complexity: 10171 vs 1047

Slide 43

Slide 43 text

1080

Slide 44

Slide 44 text

Global impact of moves

Slide 45

Slide 45 text

6 8 9 5 7 9 6 6 3 5 4 7 6 5 6 8 5 7 6 6 3 4 5 8 5 7 6 3 5 5 6 3 6 MAX MIN MAX MIN MAX Traditional Seach

Slide 46

Slide 46 text

6 8 9 5 7 9 6 6 3 5 4 7 6 5 6 8 5 7 6 6 3 4 5 8 5 7 6 3 5 5 6 3 6 MAX MIN MAX MIN MAX Evaluation Function

Slide 47

Slide 47 text

No content

Slide 48

Slide 48 text

Monte Carlo Method

Slide 49

Slide 49 text

What is Pi?

Slide 50

Slide 50 text

How do you determine Pi?

Slide 51

Slide 51 text

No content

Slide 52

Slide 52 text

2006

Slide 53

Slide 53 text

Browne, Cb, and Edward Powley. 2012. A survey of monte carlo tree search methods. Intelligence and AI 4, no. 1: 1-49

Slide 54

Slide 54 text

2/4 1/1 0/1 1/1 0/1 A1 D5 F13 C7

Slide 55

Slide 55 text

2/4 1/1 0/1 1/1 0/1 A1 D5 F13 C7 Selection

Slide 56

Slide 56 text

2/4 1/1 0/1 1/1 0/1 A1 D5 F13 C7 0/0 B5 Expansion

Slide 57

Slide 57 text

2/4 1/1 0/1 1/1 0/1 A1 D5 F13 C7 0/0 B5 Simulation

Slide 58

Slide 58 text

Random

Slide 59

Slide 59 text

Not Human like?

Slide 60

Slide 60 text

3/5 2/2 0/1 1/1 0/1 A1 D5 F13 C7 1/1 B5 Backpropagation

Slide 61

Slide 61 text

3/5 2/2 0/1 1/1 0/1 A1 D5 F13 C7 1/1 B5 Perspective

Slide 62

Slide 62 text

2/5 1/2 0/1 1/1 0/1 A1 D5 F13 C7 1/1 B5 Perspective

Slide 63

Slide 63 text

Multi Armed Bandit

Slide 64

Slide 64 text

Multi Armed Bandit Exploitation vs Exploration

Slide 65

Slide 65 text

wins visits +explorationFactor √ln(totalVisits) visits

Slide 66

Slide 66 text

15042 86/193 0/1 1/2 0/2 36/1116 2/2 58/151 1/2 0/2 3/3

Slide 67

Slide 67 text

15042 86/193 0/1 1/2 0/2 36/1116 2/2 58/151 1/2 0/2 3/3

Slide 68

Slide 68 text

15042 86/193 0/1 1/2 0/2 36/1116 2/2 58/151 1/2 0/2 3/3

Slide 69

Slide 69 text

Generate a valid random move

Slide 70

Slide 70 text

Who has won?

Slide 71

Slide 71 text

No content

Slide 72

Slide 72 text

General Game Playing

Slide 73

Slide 73 text

Anytime

Slide 74

Slide 74 text

Lazy

Slide 75

Slide 75 text

No content

Slide 76

Slide 76 text

Expert Knowledge

Slide 77

Slide 77 text

Neural Networks

Slide 78

Slide 78 text

2014

Slide 79

Slide 79 text

What does this even mean?

Slide 80

Slide 80 text

Neural Networks

Slide 81

Slide 81 text

Input “Hidden” Layer Output Neural Networks

Slide 82

Slide 82 text

Weights

Slide 83

Slide 83 text

Bias/Threshold

Slide 84

Slide 84 text

4 2 -3 3.2 Activation

Slide 85

Slide 85 text

5.2 >= 4 2 -3 3.2 Activation

Slide 86

Slide 86 text

2.2 <= 4 2 -3 3.2 Activation

Slide 87

Slide 87 text

Activation

Slide 88

Slide 88 text

Training

Slide 89

Slide 89 text

Adjust parameters

Slide 90

Slide 90 text

Supervised Learning Input Expected Output

Slide 91

Slide 91 text

Backpropagation

Slide 92

Slide 92 text

Data set

Slide 93

Slide 93 text

Training data + test data

Slide 94

Slide 94 text

Training

Slide 95

Slide 95 text

Verify

Slide 96

Slide 96 text

Overfitting

Slide 97

Slide 97 text

Deep Neural Networks

Slide 98

Slide 98 text

Convolutional Neural Networks

Slide 99

Slide 99 text

Local Receptive Field

Slide 100

Slide 100 text

Feature Map

Slide 101

Slide 101 text

Stride

Slide 102

Slide 102 text

Shared weights and biases

Slide 103

Slide 103 text

19 x 19 3 x 17 x 17 Multiple Feature maps/filters

Slide 104

Slide 104 text

Architecture ... Input Features 12 layers with 64 – 192 filters Output

Slide 105

Slide 105 text

Architecture ... Input Features 12 layers with 64 – 192 filters Output

Slide 106

Slide 106 text

Architecture ... Input Features 12 layers with 64 – 192 filters Output

Slide 107

Slide 107 text

2.3 million parameters 630 million connections

Slide 108

Slide 108 text

● Stone Colour x 3 ● Liberties x 4 ● Liberties after move played x 6 ● Legal Move x 1 ● Turns since x 5 ● Capture Size x 7 ● Ladder Move x 1 ● KGS Rank x 9 Input Features

Slide 109

Slide 109 text

Training on game data predicting the next move

Slide 110

Slide 110 text

55% Accuracy

Slide 111

Slide 111 text

Mostly beats GnuGo

Slide 112

Slide 112 text

Combined with MCTS in the Selection

Slide 113

Slide 113 text

Asynchronous GPU Power

Slide 114

Slide 114 text

Revolution

Slide 115

Slide 115 text

Silver, D. et al., 2016. Mastering the game of Go with deep neural networks and tree search. Nature, 529(7587), p.484-489. Networks in Training

Slide 116

Slide 116 text

Silver, D. et al., 2016. Mastering the game of Go with deep neural networks and tree search. Nature, 529(7587), p.484-489. Networks in Training

Slide 117

Slide 117 text

Silver, D. et al., 2016. Mastering the game of Go with deep neural networks and tree search. Nature, 529(7587), p.484-489. AlphaGo Search

Slide 118

Slide 118 text

Selection

Slide 119

Slide 119 text

Action Value Prior Probability Visit Count Selection

Slide 120

Slide 120 text

Action Value Prior Probability Visit Count

Slide 121

Slide 121 text

Action Value Prior Probability Visit Count Selection

Slide 122

Slide 122 text

Action Value Prior Probability Visit Count Selection

Slide 123

Slide 123 text

0.8 1.2 0.5 1.1 0.9 Action Value + Bonues

Slide 124

Slide 124 text

0.8 1.2 0.5 1.1 0.9 Expansion

Slide 125

Slide 125 text

0.8 1.2 0.5 1.1 0.9 Expansion

Slide 126

Slide 126 text

0.8 1.2 0.5 1.1 0.9 Prior Probability

Slide 127

Slide 127 text

0.8 1.2 0.5 1.1 0.9 Evalution

Slide 128

Slide 128 text

0.8 1.2 0.5 1.1 0.9 Evalution

Slide 129

Slide 129 text

0.8 1.2 0.5 1.1 0.9 Rollout

Slide 130

Slide 130 text

0.8 1.2 0.5 1.1 0.9 Value Network

Slide 131

Slide 131 text

0.81 1.3 0.5 1.1 0.9 Backup 1.6

Slide 132

Slide 132 text

1202 CPUs 176 GPUS 0.8 1.2 0.5 1.1 0.9

Slide 133

Slide 133 text

Tensor

Slide 134

Slide 134 text

Human Instinct Policy Network Reading Capability Search Positional Judgement Value Network 3 Strengths of AlphaGo

Slide 135

Slide 135 text

Human Instinct Policy Network Reading Capability Search Positional Judgement Value Network Most Important Strength

Slide 136

Slide 136 text

More Natural

Slide 137

Slide 137 text

Lee Sedol match

Slide 138

Slide 138 text

Style

Slide 139

Slide 139 text

So when AlphaGo plays a slack looking move, we may regard it as a mistake, but perhaps it should more accurately be viewed as a declaration of victory? An Younggil 8p

Slide 140

Slide 140 text

Game 2

Slide 141

Slide 141 text

Game 4

Slide 142

Slide 142 text

No content

Slide 143

Slide 143 text

Game 4

Slide 144

Slide 144 text

Game 4

Slide 145

Slide 145 text

What can we learn?

Slide 146

Slide 146 text

Making X faster vs Doing less of X

Slide 147

Slide 147 text

Benchmark everything

Slide 148

Slide 148 text

Solving problems the human way vs Solving problems the computer way

Slide 149

Slide 149 text

Don't blindly dismiss approaches as infeasible

Slide 150

Slide 150 text

One Approach vs Combination of Approaches

Slide 151

Slide 151 text

Joy of Creation

Slide 152

Slide 152 text

PragTob/Rubykon

Slide 153

Slide 153 text

pasky/michi

Slide 154

Slide 154 text

What did AlphaGo do to beat the strongest human Go player? Tobias Pfeiffer @PragTob pragtob.info

Slide 155

Slide 155 text

Sources ● Maddison, C.J. et al., 2014. Move Evaluation in Go Using Deep Convolutional Neural Networks. ● Silver, D. et al., 2016. Mastering the game of Go with deep neural networks and tree search. Nature, 529(7587), p.484-489. ● Michael A. Nielsen, "Neural Networks and Deep Learning", Determination Press, 2015 http://neuralnetworksanddeeplearning.com ● Gelly, S. & Silver, D., 2011. Monte-Carlo tree search and rapid action value estimation in computer Go. Artificial Intelligence, 175(11), p.1856-1876. ● I. Althöfer, “On the Laziness of Monte-Carlo Game Tree Search In Non-tight Situations,” Friedrich-Schiller Univ., Jena, Tech. Rep., 2008. ● Browne, C. & Powley, E., 2012. A survey of monte carlo tree search methods. IEEE Transactions on Intelligence and AI in Games, 4(1), p.1-49. ● Gelly, S. & Silver, D., 2007. Combining online and offline knowledge in UCT. Machine Learning, p.273-280. ● https://www.youtube.com/watch?v=LX8Knl0g0LE&index=9&list=WL

Slide 156

Slide 156 text

Photo Credit ● http://www.computer-go.info/events/ing/2000/images/bigcup.jpg ● https://en.wikipedia.org/wiki/File:Kasparov-29.jpg ● http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-titan-black/product-images ● http://giphy.com/gifs/dark-thread-after-lCP95tGSbMmWI ● https://cloudplatform.googleblog.com/2016/05/Google-supercharges-machine-learning-tasks-with-custom-chi p.html ● https://gogameguru.com/i/2016/01/Fan-Hui-vs-AlphaGo-550x364.jpg ● http://makeitstranger.com/ ● CC BY 2.0 – https://en.wikipedia.org/wiki/File:Deep_Blue.jpg – https://www.flickr.com/photos/luisbg/2094497611/ ● CC BY-SA 3.0 – https://en.wikipedia.org/wiki/Alpha%E2%80%93beta_pruning#/media/File:AB_pruning.svg ● CC BY-SA 2.0 – https://flic.kr/p/cPUtny – https://flic.kr/p/dLSKTQ – https://www.flickr.com/photos/83633410@N07/7658272558/

Slide 157

Slide 157 text

Photo Credit ● CC BY-NC-ND 2.0 – https://flic.kr/p/q15pzb – https://flic.kr/p/bHSj7D – https://flic.kr/p/ixSsfM – https://www.flickr.com/photos/waxorian/4228645447/ – https://www.flickr.com/photos/pennstatelive/8972110324/ – https://www.flickr.com/photos/dylanstraub/6428496139/ ● https://en.wikipedia.org/wiki/Alphabet_Inc.#/media/File:Alphabet_Inc_Logo_2015.svg ● CC BY 3.0 – https://en.wikipedia.org/wiki/File:Pi_30K.gif