Artificial Intelligence: Prospects for the 21st Century Henry Kautz Department of Computer Science University of Rochester What is Artificial Intelligence? • Study of principles for understanding and building intelligent agents – – – – – – Human, animal, or mechanical How to perceive the world How to reason and make decisions How to learn How to act (motion, speech) How to cooperate with other agents Can’t Win Definition of AI • AI = making a computer solve a problem that requires human intelligence – By definition, any problem solved by AI no longer requires human intelligence – So, AI never succeeds! • Useful idea: study tasks people perform in order to understand intelligence Outline • Approaches to AI – Task based (“Classical AI”) – Neural networks • Which Way Will Achieve AI? – Criticisms – Ray Kurzweil’s Perspective – A Middle Ground Classical AI • The principles of intelligence are separate from the hardware (or “wetware”) • Look for these principles by studying how to perform individual tasks that require intelligence Success Story: Medical Expert Systems • 1980: First expert level performance – diagnosis of blood infections • Today: 1,000’s of systems – Often outperform doctors Success Story: Chess I could feel – I could smell – a new kind of intelligence across the table - Garry Kasparov (1997) •Examines 5 billion positions / second •Intelligent behavior emerges from brute-force search Success Story: Robotics (1) Rendezvoused with an asteroid, 1998-2000 Capable of autonomous diagnosis & repair Success Story: Robotics (2) • DARPA Grand Challenges, 2004-2007 – Races in desert and urban environments by fully autonomous vehicles – Succeeded with “off the shelf” AI technology! Success Story: Text to Speech • Kurzweil Reading Machines, 1978-2006 Neural Networks • Develop computational models of the brain at the neural level – McCulloch & Pitts model (1943): very simple, but a pretty good approximation of most real neurons Success Story: Face Recognition • Programming a neural net that learns to recognize faces can now be done as homework problem! Success Story: Brain-Computer Interfaces Miguel Nicolelis (2003), Duke University Success Story: MRI Imaging of Specific Thoughts Tools Buildings • Tom Mitchell (CMU) 2006 Food Which Approach Will Achieve AI? • Criticism of Classical AI: – Successes so far are in all narrow domains – We can never explicitly program enough “commonsense” into a AI system to make it a true general intelligence – The human brain has a completely different architecture than a modern computer Which Approach Will Achieve AI? • Criticism of Neural Networks: – Successes so far are in all narrow domains – Building an AI by studying neural processes is like trying to reverseengineer Windows Vista by watching bits – “Summation and threshold” is just another kind of logic gate! A Middle Ground • Most AI researchers (including me) believe that AI will be accomplished by a combination of ideas from both camps – Studying tasks tells us what needs to be computed – Studying brains tells us what classes of algorithms are possible – We can implement those algorithms in many ways A Middle Ground • Neural nets are not necessary the best way to implement all the thing the brain does! – Evolution rarely produces optimal solutions! • Machine learning is compatible with both the classical and neural net approaches – Learning from text on the Internet will solve the problem of getting enough “commonsense” information Pioneering an Emerging Area • Assisted Cognition – Computer systems that enhance the abilities, independence, and safety of persons with cognitive disabilities • Aging and age-related diseases • Brain injury • Developmental disabilities – Computer caregivers Examples • Maintaining a daily schedule – Compensating for memory problems – Compensating for lowered self-initiative – Step-by-step task prompting • Navigation – Indoors and outdoors • Safety and health – Need for immediate help – Long term health trends Activity of Daily Living Monitoring • Goal: Accurate, automated ADL logs – Changes in routine often precursor to illness, accidents – Human monitoring intrusive & inaccurate Object-Based Activity Recognition • Activities of daily living involve the manipulation of many physical objects – Kitchen: stove, pans, dishes, … – Bathroom: toothbrush, shampoo, towel, … – Bedroom: linen, dresser, clock, clothing, … • We can recognize activities from a time-sequence of object touches Sensing Object Manipulation • RFID: Radiofrequency identification tags – – – – Small Semi-passive Durable Cheap • Near future: use products’ own tags Wearable RFID Reader • Bracelet reads tags near hand, transmits information wirelessly to monitoring system • Soon will be built into a wristwatch Interpreting the Sensor Data: Machine Learning • Machine learning algorithms automatically create the recognition system from training examples • Can handle sensor noise and user errors Using Commonsense Knowledge • Can further improve the system by adding “commonsense knowledge” • Example: a travel mug is like a cup Results: Detecting ADLs Activity Prior Work SHARP RFID Legend Personal Appearance 92/92 Oral Hygiene 70/78 Toileting 73/73 Washing up 100/33 Appliance Use 100/75 Use of Heating 84/78 Care of clothes and linen 100/73 Making a snack 100/78 Making a drink 75/60 Use of phone 64/64 Leisure Activity 100/79 Infant Care 100/58 Medication Taking 100/93 Housework 100/82 General solution Point solution Inferring ADLs from Interactions with Objects Philipose, Fishkin, Perkowitz, Patterson, Hähnel, Fox, and Kautz IEEE Pervasive Computing, 4(3), 2004 All Watched Over by Machines of Loving Grace, by Richard Brautigan I like to think (it has to be!) of a cybernetic ecology where we are free of our labors and joined back to nature, returned to our mammal brothers and sisters, and all watched over by machines of loving grace.