Instructor’s Solution Manual Artificial Intelligence A Modern Approach Fourth Edition Stuart J. Russell and Peter Norvig

Instructor’s Solution Manual Artificial Intelligence A Modern Approach Fourth Edition Stuart J. Russell and Peter Norvig-Define in your own words: (a) intelligence, (b) artificial intelligence, (c) agent, (d) rationality ...

Instructor’s Solution Manual Artificial Intelligence A Modern Approach Fourth Edition Stuart J. Russell and Peter Norvig-Define in your own words: (a) intelligence, (b) artificial intelligence, (c) agent, (d) rationality, (e) logical reasoning. Exercise 1.1.#TURI Read Turing’s original paper on AI (Turing, 1950). In the paper, he discusses several objectionsto his proposed enterprise and histest for intelligence. Which objectionsstill carry EXERCISES 1 INTRODUCTION Note that for many of the questions in this chapter, we give references where answers can be found rather than writing them out—the full answers would be far too long. 1.1 What Is AI? a. Dictionary definitions of intelligence talk about “the capacity to acquire and apply knowledge” or “the faculty of thought and reason” or “the ability to comprehend and profit from experience.” These are all reasonable answers, but if we want something quantifiable we would use something like “the ability to act successfully across a wide range of objectives in complex environments.” b. We define artificial intelligence as the study and construction of agent programs that perform well in a given class of environments, for a given agent architecture; they do the right thing. An important part of that is dealing with the uncertainty of what the current state is, what the outcome of possible actions might be, and what is it that we really desire. c. We define an agent as an entity that takes action in response to percepts from an environment. d. We define rationality as the property of a system which does the “right thing” given what it knows. See Section 2.2 for a more complete discussion. The basic concept is perfect rationality; Section ?? describes the impossibility of achieving perfect rationality and proposes an alternative definition. e. We define logical reasoning as the a process of deriving new sentences from old, such that the new sentences are necessarily true if the old ones are true. (Notice that does not refer to any specific syntax or formal language, but it does require a well-defined notion of truth.) Section 1.1 What Is AI? 3 Exercise 1.1.#REFL Are reflex actions (such as flinching from a hot stove) rational? Are they intelligent? Exercise 1.1.#SYAI To what extent are the following computer systems instances of artificial intelligence: • Supermarket bar code scanners. • Web search engines. • Voice-activated telephone menus. • Spelling and grammar correction features in word processing programs. • Internet routing algorithms that respond dynamically to the state of the network. See the solution for exercise 26.1 for some discussion of potential objections. The probability of fooling an interrogator depends on just how unskilled the interrogator is. A few entrants in the Loebner prize competitions have fooled judges, although if you look at the transcripts, it looks like the judges were having fun rather than taking their job seriously. There certainly have been examples of a chatbot or other online agent fooling humans. For example, see the description of the Julia chatbot at www.lazytd.com/lti/ julia/. We’d say the chance today is something like 10%, with the variation depending more on the skill of the interrogator rather than the program. In 25 years, we expect that the entertainment industry (movies, video games, commercials) will have made sufficient investments in artificial actors to create very credible impersonators. Note that governments and international organizations are seriously considering rules that require AI systems to be identified as such. In California, it is already illegal for machines to impersonate humans in certain circumstances. Yes, they are rational, because slower, deliberative actions would tend to result in more damage to the hand. If “intelligent” means “applying knowledge” or “using thought and reasoning” then it does not require intelligence to make a reflex action. • Although bar code scanning is in a sense computer vision, these are not AI systems. The problem of reading a bar code is an extremely limited and artificial form of visual interpretation, and it has been carefully designed to be as simple as possible, given the hardware. • In many respects. The problem of determining the relevance of a web page to a query is a problem in natural language understanding, and the techniques are related to those