An Introduction to Artificial Intelligence, Machine Learning, and Neural networks. Carola F. Berger

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3 An Introduction to Artificial Intelligence, Machine Learning, and Neural networks ATA58 Carola F. Berger

4 Outline What is Artificial Intelligence (AI)? What does it do? How does it work? Will there be a robot apocalypse? References and Further Reading Carola F. Berger, AI and Neural Nets, ATA58 2

5 What is AI? What is intelligence? Carola F. Berger, AI and Neural Nets, ATA58 3

6 What is AI? What is intelligence? Merriam-Webster: the ability to learn or understand or to deal with new or trying situations Carola F. Berger, AI and Neural Nets, ATA58 3

7 What is AI? What is intelligence? turingarchive.org Carola F. Berger, AI and Neural Nets, ATA58 4

8 What is AI? What is intelligence? Carola F. Berger, AI and Neural Nets, ATA58 5

9 What is AI? What is machine learning? Carola F. Berger, AI and Neural Nets, ATA58 6

10 What is AI? What is machine learning? Machine learning is a fancy way of saying finding patterns in data. Kirti Vashee Carola F. Berger, AI and Neural Nets, ATA58 6

11 What is AI? What is deep learning? Hagmann P, Cammoun L, Gigandet X, Meuli R, Honey CJ, Wedeen VJ, Sporns O (2008) Mapping the structural core of human cerebral cortex. PLoS Biology Vol. 6, No. 7, e159. Carola F. Berger, AI and Neural Nets, ATA58 7

12 What is AI? What is deep learning? Artificial neural nets are not a new idea: W. McCulloch, W. Pitts, 1943 D. O. Hebb, 1949 B. G. Farley, W. A. Clark, 1954 Carola F. Berger, AI and Neural Nets, ATA58 8

13 What is AI? Adapted from: S. Jurvetson, Carola F. Berger, AI and Neural Nets, / ATA58 9

14 What does AI do? Carola F. Berger, AI and Neural Nets, ATA58 10

15 What does AI do? Play games and win Carola F. Berger, AI and Neural Nets, ATA58 11

16 What does AI do? Automated classification Object recognition Recommender systems Carola F. Berger, AI and Neural Nets, ATA58 12

17 What does AI do? Predictive typing Text-to-speech, speech-to-text (Neural) machine translation Carola F. Berger, AI and Neural Nets, ATA58 13

18 What does AI do? Financial trading Legal assistance Carola F. Berger, AI and Neural Nets, ATA58 14

19 What does AI do? Self-driving cars Carola F. Berger, AI and Neural Nets, ATA58 15

20 What does AI do? Chat and social media bots Carola F. Berger, AI and Neural Nets, ATA58 16

21 What does AI do? Design inspirational posters Carola F. Berger, AI and Neural Nets, ATA58 17

22 What does AI do? Name rescued guinea pigs J. Shane, Carola F. Berger, AI and Neural Nets, ATA58 18

23 What does AI do? Supervised learning Unsupervised learning Carola F. Berger, AI and Neural Nets, ATA58 19

24 How does it work? Carola F. Berger, AI and Neural Nets, ATA58 20

25 Neuron: How does it work? Bruce Blaus, Carola F. Berger, AI and Neural Nets, ATA58 21

26 How does it work? Unit in artificial neural net: Carola F. Berger, AI and Neural Nets, ATA58 22

27 How does it work? Unit in artificial neural net: Carola F. Berger, AI and Neural Nets, ATA58 22

28 How does it work? Neural network: Hagmann P, Cammoun L, Gigandet X, Meuli R, Honey CJ, Wedeen VJ, Sporns O (2008) Mapping the structural core of human cerebral cortex. PLoS Biology Vol. 6, No. 7, e159. Carola F. Berger, AI and Neural Nets, ATA58 23

29 How does it work? Neural network: Adapted from: Cburnett, Carola F. Berger, AI and Neural Nets, ATA58 24

30 How does it work? Neural network training: Feed in training data Adapt weights ( arrows ) according to difference between desired output and actual output, e.g. by backpropagation Adapted from: Cburnett, Carola F. Berger, AI and Neural Nets, ATA58 25

31 Autopsy of a Neural Net Carola F. Berger, AI and Neural Nets, ATA58 26

32 Autopsy of a Neural Net Neural net to recognize hand-written digits Carola F. Berger, AI and Neural Nets, ATA58 27

33 Autopsy of a Neural Net Neural net to recognize hand-written digits Carola F. Berger, AI and Neural Nets, ATA58 28

34 Autopsy of a Neural Net Sample input (20x20 pixels) Carola F. Berger, AI and Neural Nets, ATA58 29

35 Autopsy of a Neural Net Sample input (20x20 pixels) Carola F. Berger, AI and Neural Nets, ATA58 29

36 Autopsy of a Neural Net Weights to hidden units Carola F. Berger, AI and Neural Nets, ATA58 30

37 Autopsy of a Neural Net Weights to hidden units feature extraction Carola F. Berger, AI and Neural Nets, ATA58 31

38 Autopsy of a Neural Net Weights to hidden units Carola F. Berger, AI and Neural Nets, ATA58 30

39 Autopsy of a Neural Net Weights to hidden units Carola F. Berger, AI and Neural Nets, ATA58 30

40 Autopsy of a Neural Net Hidden units to output Carola F. Berger, AI and Neural Nets, ATA58 31

41 Autopsy of a Neural Net Hidden units to output Carola F. Berger, AI and Neural Nets, ATA58 31

42 Autopsy of a Neural Net Hidden units to output Carola F. Berger, AI and Neural Nets, ATA58 31

43 Autopsy of a Neural Net Internal conv. 2 Input Internal convolution Hidden Output Carola F. Berger, AI and Neural Nets, ATA58 32

44 Autopsy of a Neural Net Internal conv. 2 Input Internal convolution Hidden Output Carola F. Berger, AI and Neural Nets, ATA58 32

45 Wrong!!! Autopsy of a Neural Net Internal conv. 2 Input Internal convolution Hidden Output Carola F. Berger, AI and Neural Nets, ATA58 32

46 Autopsy of a Neural Net What happens with unknowns? Klingon 6 [jav] Input Internal convolution Hidden Output Carola F. Berger, AI and Neural Nets, ATA58 33

47 Autopsy of a Neural Net Klingon 6 [jav] Internal conv. 2 Input Internal convolution Hidden Output Carola F. Berger, AI and Neural Nets, ATA58 33

48 Neural Nets - Recap ü Training = extraction of features (=patterns) from training data Carola F. Berger, AI and Neural Nets, ATA58 34

49 Neural Nets - Recap ü Training = extraction of features (=patterns) from training data ü The more hidden layers and hidden units, the more parameters (possible overfitting!) Carola F. Berger, AI and Neural Nets, ATA58 34

50 Neural Nets - Recap ü Training = extraction of features (=patterns) from training data ü The more hidden layers and hidden units, the more parameters (possible overfitting!) ü Beware: Garbage in -> worse garbage out! Carola F. Berger, AI and Neural Nets, ATA58 34

51 Neural Nets - Recap ü Training = extraction of features (=patterns) from training data ü The more hidden layers and hidden units, the more parameters (possible overfitting!) ü Beware: Garbage in -> worse garbage out! ü ANNs work well for pattern recognition after training, including context Carola F. Berger, AI and Neural Nets, ATA58 34

52 Neural Nets - Recap ü Training = extraction of features (=patterns) from training data ü The more hidden layers and hidden units, the more parameters (possible overfitting!) ü Beware: Garbage in -> worse garbage out! ü ANNs work well for pattern recognition after training, including context ü Completely unpredictable when confronted with new, hitherto unknown data Carola F. Berger, AI and Neural Nets, ATA58 34

53 Neural Nets - Recap Recall: Definition of intelligence according to Merriam-Webster: the ability to learn or understand or to deal with new or trying situations Carola F. Berger, AI and Neural Nets, ATA58 35

54 Is the Robot Apocalypse near? Carola F. Berger, AI and Neural Nets, ATA58 36

55 Is the Robot Apocalypse near? the-real-threat-is-machine-incompetence-not-intelligence Carola F. Berger, AI and Neural Nets, ATA58 37

56 Is the Robot Apocalypse near? Carola F. Berger, AI and Neural Nets, ATA58 38

57 Will We be Replaced by Robots? Survey among 352 AI researchers: K. Grace et al., When Will AI Exceed Human Performance? Evidence from AI Experts, Carola F. Berger, AI and Neural Nets, ATA58 39

58 Will We be Replaced by Robots? Survey among 352 AI researchers: K. Grace et al., When Will AI Exceed Human Performance? Evidence from AI Experts, Carola F. Berger, AI and Neural Nets, ATA58 39

59 Will We be Replaced by Robots? Survey among 352 AI researchers: K. Grace et al., When Will AI Exceed Human Performance? Evidence from AI Experts, Carola F. Berger, AI and Neural Nets, ATA58 40

60 References & Further Reading Slides at: A. Turing, Computing machinery and intelligence, MIND: A Quarterly Review of Psychology and Philosophy, Vol. LIX, No.236, Oct. 1950, A. Ng, Machine Learning, Coursera, S. Russell, P. Norvig, Artificial Intelligence: A Modern Approach, 3 rd Ed., Prentice Hall, Carola F. Berger, AI and Neural Nets, ATA58 41