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Alexander Yates. An Introduction to Artificial Intelligence. Temple University Computer and Information Sciences. Popular Conception of Artificial Intelligence. Artificial Intelligence, more realistically. Autonomous Navigation. Boston Dynamics’ Big Dog (or fly-dog) 0:30, 1:25
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Alexander Yates An Introduction to Artificial Intelligence Temple University Computer and Information Sciences
Autonomous Navigation • Boston Dynamics’ Big Dog (or fly-dog) • 0:30, 1:25 • Self-driving cars • DARPA’s Grand Challenge “Ghostrider” (DARPA Grand Challenge entry) • 1:00, 2:20 • Google’s self-driving car: http://www.youtube.com/watch?v=cdgQpa1pUUE 0:30-1:00
What is Artificial Intelligence? It’s the science of making machines behave as if they understand the world the way humans do. Specifically, AI researchers build machines that can • know (or believe) • reason • learn • communicate (talk and listen)
Expert Systems: Machines than can know and reason Idea: Make a machine that’s better than a human expert. Early example: • MYCIN: identifies bacteria causing severe infections, such as bacteremia and meningitis. • It could propose an acceptable therapy in about 69% of cases, which was better than the performance of infectious disease experts who were judged using the same criteria.
Expert Systems: Machines than can reason Second example: Chinook Schaeffer et al.: "Checkers Is Solved“ (2007) • They proved that the best an opponent can do against their “Chinook” system is to draw. • It had already been world champion since 1994 Interesting Sidebar: Dr. Marion Tinsley (February 3, 1927–April 3, 1995) is considered the greatest checkers player who ever lived. He was world champion from 1955–1958 and 1975–1991. Tinsley never lost a World Championship match, and lost only nine games(two of them to the Chinook computer program) in his entire 45 year career. He withdrew from championship play during the years 1958–1975, relinquishing the title during that time.
Machines that can learn One of the more recent advances of AI has been the development of systems that can • Learn from training • Learn from experience • Adapt to changing conditions 20-25 years ago, this was crazy. Now, there are toolkits: e.g., WEKA and LibSVM
Machines that can learn Some sample applications: • Machines that can determine the amount of air pollution, based on satellite readings • Software that can detect network intruders based on network traffic patterns • Programs that can diagnose tumors based on MRI scans and CAT scans All of these are available today.
Conversational Agents: Machines that can hold a conversation • Chomsky chatbot demo • Video of two chatbots talking with each other • Speech Recognition • (e.g., Siri) • You’ve probably interacted with this many times • Right now, so-so accuracy, but it’s going to change human-machine interactions
Some problems for AI: • How can you make a machine know(or believe)? • How can you make a machine think (or reason)? 3. How can you make machines perceive and act upon the real world?
Computational Linguistics Computational linguistics is the area of AI that deals with language. A brief tour of computational linguistics today: • Machine translation • Question Answering • Information retrieval • Information Extraction
Machine Translation Machine translation is the task of translating automatically between languages, like a human interpreter would. • Google translate demo • English Malay Hungarian English • “I think, Watson, that you have put on seven and a half pounds since I saw you.” • Very hard problem – it’s considered “AI-complete” • But a solution is worth $$$$$
Information Retrieval Information retrieval = Web search (the Google kind) The academic study focuses on how to best find the most informative document in a large collection. 1996: 2 Stanford students start working on an information retrieval system called “BackRub” 2004: Their company, Google, has its IPO and makes them billionaires.
Question Answering Question Answering is the task of finding a specific answer to an arbitrary question in English, using the Web. Watson Qualim demo
Information Extraction Definition: The automatic extraction of structured information from unstructured documents. Overall Goals: Making information more accessible to people Making information machine-processable Practical Goal: Build large databases from the information contained in text TextRunner Demo
How AI fits into Computer Science Databases Approximation Algorithms and SAT Solvers Human Computer Interaction AI Data Mining Theory Bug Detection, Fault Analysis Software Engineering Graphics Systems Expert Systems and Applications Autonomous Video Game Characters
Why study or work on AI? • It’s exciting – everything is always changing! • True in Computer Science, especially true for AI • Pressure to innovate: we’re so far from true AI, we have to constantly re-think how we’re doing things • It’s useful and it works • AI ideas show up everywhere in everyday life • It can have a huge impact
Impact of AI Some of AI’s contributions to the world: • Fraud detection by banks • Control systems for car brakes • Automatic Zip Code readers used by the U.S.P.S. • License plate recognition for EZ-Pass • Logistic planning used by U.S. Army since the first Iraq War (saving more money than ever was invested into AI research by the government) • Deep Blue, and other games • Intelligent user interfaces • Google & web search • Mars rovers • …
Impact of Computational Linguistics • Web search • Speech Recognition • Speech interfaces used in car GPS systems • Automatic Arabic translators used by the U.S. Army • Semantic Web applications (eg, Google News) • Faster desktop search applications • Siri • … • Many more to come (still a young field)