n. (Abbr. AI)
- The ability of a computer or other machine to perform those activities that are normally thought to require intelligence.
- The branch of computer science concerned with the development of machines having this ability.
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| Dictionary: artificial intelligence |
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| Sci-Tech Encyclopedia: Artificial intelligence |
The subfield of computer science concerned with understanding the nature of intelligence and constructing computer systems capable of intelligent action. It embodies the dual motives of furthering basic scientific understanding and making computers more sophisticated in the service of humanity.
Many activities involve intelligent action—problem solving, perception, learning, planning and other symbolic reasoning, creativity, language, and so forth—and therein lie an immense diversity of phenomena. Scientific concern for these phenomena is shared by many fields, for example, psychology, linguistics, and philosophy of mind, in addition to artificial intelligence. The starting point for artificial intelligence is the capability of the computer to manipulate symbolic expressions that can represent all manner of things, including knowledge about the structure and function of objects and people in the world, beliefs and purposes, scientific theories, and the programs of action of the computer itself.
Artificial intelligence is primarily concerned with symbolic representations of knowledge and heuristic methods of reasoning, that is, using common assumptions and rules of thumb. Two examples of problems studied in artificial intelligence are planning how a robot, or person, might assemble a complicated device, or move from one place to another; and diagnosing the nature of a person's disease, or of a machine's malfunction, from the observable manifestations of the problem. In both cases, reasoning with symbolic descriptions predominates over calculating.
The approach of artificial intelligence researchers is largely experimental, with small patches of mathematical theory. As in other experimental sciences, investigators build devices (in this case, computer programs) to carry out their experimental investigations. New programs are created to explore ideas about how intelligent action might be attained, and are also developed to test hypotheses about concepts or mechanisms involved in intelligent behavior.
The foundations of artificial intelligence are divided into representation, problem-solving methods, architecture, and knowledge. To work on a task, a computer must have an internal representation in its memory, for example, the symbolic description of a room for a moving robot, or a set of features describing a person with a disease. The representation also includes all the knowledge, including basic programs, for testing and measuring the structure, plus all the programs for transforming the structure into another one in ways appropriate to the task. Changing the representation used for a task can make an immense difference, turning a problem from impossible to trivial.
Given the representation of a task, a method must be adopted that has some chance of accomplishing the task. Artificial intelligence has gradually built up a stock of relevant problem-solving methods (the so-called weak methods) that apply extremely generally.
An important feature of all the weak methods is that they involve search. One of the most important generalizations to arise in artificial intelligence is the ubiquity of search. It appears to underlie all intelligent action. In the worst case, the search is blind. In heuristic search extra information is used to guide the search.
Some of the weak methods are generate-and-test (a sequence of candidates is generated, each being tested for solutionhood); hill climbing (a measure of progress is used to guide each step); means-ends analysis (the difference between the desired situation and the present one is used to select the next step); impasse resolution (the inability to take the desired next step leads to a subgoal of making the step feasible); planning by abstraction (the task is simplified, solved, and the solution used as a guide); and matching (the present situation is represented as a schema to be mapped into the desired situation by putting the two in correspondence).
An intelligent agent—person or program—has multiple means for representing tasks and dealing with them. Also required is an architecture or operating framework within which to select and carry out these activities. Often called the executive or control structure, it is best viewed as a total architecture (as in computer architecture), that is, a machine that provides data structures, operations on those data structures, memory for holding data structures, accessing operations for retrieving data structures from memory, a programming language for expressing integrated patterns of conditional operations, and an interpreter for carrying out programs. Any digital computer provides an architecture, as does any programming language. Architectures are not all equivalent, and one important scientific question is what architecture is appropriate for a general intelligent agent.
In artificial intelligence, the basic paradigm of intelligent action is that of search through a space of partial solutions (called the problem space) for a goal situation. Each step offers several possibilities, leading to a cascading of possibilities that can be represented as a branching tree. The search is thus said to be combinatorial or exponential. For example, if there are 10 possible actions in any situation, and it takes a sequence of 12 steps to find a solution (a goal state), then there are 1012 possible sequences in the exhaustive search tree. What keeps the search under control is knowledge, which suggests how to choose or narrow the options at each step. Thus the fourth fundamental concern is how to represent knowledge in the memory of the system so it can be brought to bear on the search when relevant.
An intelligent agent will have immense amounts of knowledge. This implies another major problem, that of discovering the relevant knowledge as the solution attempt progresses. Although this search does not include the combinatorial explosion characteristic of searching the problem space, it can be time consuming and hard. However, the structure of the database holding the knowledge (called the knowledge base) can be carefully tailored to suit the architecture in order to make the search efficient. This knowledge base, with its accompanying problems of encoding and access, constitutes the final ingredient of an intelligent system.
An example of artificial intelligence is computer perception. Perception is the formation, from a sensory signal, of an internal representation suitable for intelligent processing. Though there are many types of sensory signals, computer perception has focused on vision and speech. Perception might seem to be distinct from intelligence, since it involves incident time-varying continuous energy distributions prior to interpretation in symbolic terms. However, all the same ingredients occur: representation, search, architecture, and knowledge. Speech perception starts with the acoustic wave of a human utterance and proceeds to an internal representation of what the speech is about. A sequence of representations is used: the digitization of the acoustic wave into an array of intensities; the formation of a small set of parametric quantities that vary continuously with time (such as the intensities and frequencies of the formants, bands of resonant energy characteristic of speech); a sequence of phons (members of a finite alphabet of labels for characteristic sounds, analogous to letters); a sequence of words; a parsed sequence of words reflecting grammatical structure; and finally a semantic data structure representing a sentence (or other utterance) that reflects the meaning behind the sounds.
A class of artificial intelligence programs called expert systems attempt to accomplish tasks by acquiring and incorporating the same knowledge that human experts have. Many attempts to apply artificial intelligence to medicine, government, and other socially significant tasks take the form of expert systems. Even though the emphasis is on knowledge, all the standard ingredients are present.
In careful tests, a number of expert systems have shown performance at levels of quality equivalent to or better than average practicing professionals (for example, average practicing physicians) on the restricted domains over which they operate. Nearly all large corporations and many smaller ones use expert systems. A common application is to provide technical assistance to persons who answer customers' trouble calls. Computer companies use expert systems to assist in configuring components from a parts catalog into a complete system that matches a customer's specifications, a kind of application that has been replicated in other industries tailoring assembled products to customers' needs. Troubleshooting and diagnostic programs are commonplace. Another widespread use of this technology is in software for home computers that assists taxpayers. One important lesson learned from incorporating artificial intelligence software into ongoing practice is that its success depends on many other aspects besides the intrinsic intellectual quality, for example, ease of interaction, integration into existing workflow, and costs.
Expert systems have sparked important insights in reasoning under uncertainty, causal reasoning, reasoning about knowledge, and acceptance of computer systems in the workplace. They illustrate that there is no hard separation between pure and applied artificial intelligence; finding what is required for intelligent action in a complex applied area makes a significant contribution to basic knowledge. See also Expert systems.
In addition to the subject areas mentioned above, significant work in artificial intelligence has been done on puzzles and reasoning tasks, induction and concept identification, symbolic mathematics, theorem proving in formal logic, natural language understanding and generation, vision, robotics, chemistry, biology, engineering analysis, computer-assisted instruction, and computer-program synthesis and verification, to name only the most prominent. As computers become smaller and less expensive, more and more intelligence is built into automobiles, appliances, and other machines, as well as computer software, in everyday use. See also Automata theory; Computer; Control systems; Cybernetics; Digital computer; Intelligent machine; Robotics.
| Modern Science: artificial intelligence |
The means of duplicating or imitating intelligence in computers, robots, or other devices, which allows them to solve problems, discriminate among objects, and respond to voice command.
| Real Estate Dictionary: Artificial Intelligence |
The ability of a computer program to evaluate information and make decisions according to pre-established criteria. This ability is exploited in such applications as Automated Mortgage Underwriting.Example: Excell Mortgage Company, using artificial intelligence, can pre-approve a large volume of mortgage applications in a short period of time. The process is totally computerized and takes applications through use of an Internet site. The computer can interact with applicants and solicit information as required for the underwriting process.
| Accounting Dictionary: Artificial Intelligence (AI) |
Umbrella terminology for several main categories of research. They include natural language systems, visual and voice recognition systems, robotic systems, and Expert Systems. Artificial intelligence generally is the attempt to build machines that think, as well as the study of mental faculties through the use of computational models. A reasoning process is involved with self-correction. Significant data are evaluated and relevant relationships, such as the determination of a warranty reserve, uncovered. The computer learns which kind of answers are reasonable and which are not. Artificial intelligence performs complicated strategies that compute the best or worst way to achieve a task or avoid an undesirable result. An example of an application is in tax planning involving tax shelter options given the client's financial position.
| Business Encyclopedia: Artificial Intelligence |
Computer systems are becoming commonplace; indeed, they are almost ubiquitous. We find them central to the functioning of most business, governmental, military, environmental, and health-care organizations. They are also a part of many educational and training programs. But these computer systems, while increasingly affecting our lives, are rigid, complex and incapable of rapid change. To help us and our organizations cope with the unpredictable eventualities of an ever-more volatile world, these systems need capabilities that will enable them to adapt readily to change. They need to be intelligent. Our national competitiveness depends increasingly on capacities for accessing, processing, and analyzing information. The computer systems used for such purposes must also be intelligent. Health-care providers require easy access to information systems so they can track health-care delivery and identify the most recent and effective medical treatments for their patients' conditions. Crisis management teams must be able to explore alternative courses of action and support decision making. Educators need systems that adapt to a student's individual needs and abilities. Businesses require flexible manufacturing and software design aids to maintain their leadership position in information technology, and to regain it in manufacturing. (Grosz and Davis, 1994)
The history of artificial intelligence (AI) predates the development of the first computing machines. On a general level, intelligence has been the subject of philosophical study for 2000 years. At the computational level, mathematician Alan Turing constructed a framework for AI during the era of analog computers.
While precise definitions are still the subject of debate, AI may be usefully thought of as the branch of computer science that is concerned with the automation of intelligent behavior. The intent of AI is to develop systems that have the ability to perceive and to learn, to accomplish physical tasks, and to emulate human decision making. AI seeks to design and develop intelligent agents as well as to understand them. Currently, the main fields of research and development include the following:
Foundations
The term "AI" was applied about 1956, giving a formal name to work that had been developing over the previous five or six years. Individuals and organizations have an abiding interest in AI for several important reasons, including the following:
During its early years AI was dominated by reliance on logic as a means of representing knowledge and on logical inference as the primary mechanism for intelligent reasoning. In the 1990s other paradigms arrived on the scene, some of which had a dramatic impact. Artificial neural networks (ANNs) were motivated by assumptions about how the brain functions— particularly the ideas of massively parallel connections, each of which performs simple computational tasks. Taken together, they represent knowledge as a property of patterns of relationships. Genetic algorithms apply principles of biological evolution to the problems of searching complex solution spaces. The programs do not use logical reasoning either, but evolve toward better and better solutions to complex problems.
Multiagent systems have recently come to the fore of AI research. This emergence has been driven by a recognition that intelligence may be reflected by the collective behaviors of large numbers of very simple interacting members of a community of agents. These agents can be computers, software modules, or virtually any object that can perceive aspects of its environment and proceed in a rational way toward accomplishing a goal.
A variety of disciplines have influenced the development of AI. These include philosophy (logic), mathematics (intractibility, computability, algorithms), psychology (cognition), engineering (computer hardware and software), and linguistics (knowledge representation and natural-language processing).
Long before the development of computers, the notion that thinking was a form of computation motivated the formalization of logic. These efforts continue today. Graph theory provided the architecture for searching a solution space for a problem. Operations research, with its focus on optimization algorithms, used graph theory and other methods to solve complex decision-making problems.
In 1950, Alan Turing proposed what has become known as the Turing Test for defining intelligent behavior. The idea was to specify requirements that a computer would have to exhibit in order to demonstrate intelligence. Briefly, the Turing Test proposes that the computer should be interrogated via telecommunications by a human. Intelligence is exhibited by the computer if the interrogator cannot tell whether there is a human or a computer at the other end. In order to pass the test, a computer would need to have capabilities for natural-language processing, knowledge representation, automated reasoning, and machine learning.
An Evolution of Applications
While computer systems have become commonplace, they are generally rigid, complex, and incapable of rapid change. According to A Report to ARPA on Twenty-First Century Intelligent Systems, for us and our organizations to cope with the unpredictable eventualities of an ever-more volatile world, these systems need capabilities that will enable them to adapt readily to change. The report argues that our national competitiveness depends increasingly on capacities for accessing, processing, and analyzing information (Grosz and Davis, 1994).
One of the early milestones in AI was Newell and Simon's General Problem Solver (GPS). The program was designed to imitate human problem-solving methods. This and other developments such as Logic Theorist and the Geometry Theorem Prover generated enthusiasm for the future of AI. Simon went so far as to assert that in the near-term future the problems that computers could solve would be coextensive with the range of problems to which the human mind has been applied.
Soon difficulties in achieving this objective began to manifest themselves. In scaling up from earlier successes, problems of intractability were encountered. A search for alternative approaches led to attempts to solve typically occurring cases in narrow areas of expertise. This prompted the development of expert systems. A seminal model was MYCIN, developed to diagnose blood infections. Having about 450 rules, MYCIN was able to perform as well as many experts. This and other expert-systems research led to the first commercial expert system, R1, implemented at Digital Equipment Corporation (DEC) to help configure orders for new computer systems. Sub-sequent to R1's implementation, it was estimated to save DEC about $40 million a year.
Other classic systems include the PROSPECTOR program for determining the probable location and type of ore deposits and the INTERNIST program for performing medical diagnosis in internal medicine.
The Future
A Report to ARPA on Twenty-First Century Intelligent Systems identified four types of systems that will have a substantial impact on applications: intelligent simulation, intelligent information resources, intelligent project coaches, and robot teams (Grosz and Davis, 1994).
Intelligent simulations generate realistic simulated worlds that enable extensive affordable training and education that can be made available any time and anywhere. Examples may be hurricane crisis management, exploration of the impacts of different economic theories, tests of products on simulated customers, and technological design—testing features through simulation that would cost millions of dollars to test using an actual prototype.
Intelligent information resources systems (IRSS) will enable easy access to information related to a specific problem. For instance, a rural doctor whose patient presents with a rare condition might use IRSS to help assess different treatments or identify new ones. An educator might find relevant background materials, including information about similar courses taught elsewhere.
Intelligent project coaches (IPC) could function as co-workers, assisting and collaborating with design or operations teams for complex systems. Such systems could remember and recall the rationale of previous decisions and, in times of crisis, explain the methods and reasoning previously used to handle that situation. An IPC for aircraft design, for example, could enhance collaboration by keeping communication flowing among the large, distributed design staff, the program managers, the customer, and the subcontractors.
Robot teams could contribute to manufacturing by operating in a dynamic environment with minimal instrumentation, thus providing the benefits of economies of scale. They could also participate in automating sophisticated laboratory procedures that require sensing, manipulation, planning, and transport.
Conclusion
AI is a young field and faces many complexities. Nonetheless, the Spring 1998 issue of AI Magazine contained articles on the following innovative applications of AI: This is suggestive of the broad potential of AI in the future.
Bibliography
AI Magazine. (Spring 1998).
Grosz, Barbara, and Davis, Randall, eds. (1994). A Report to ARPA on Twenty-First Century Intelligent Systems.
Luger, George F., and Stubblefield, William A. (1998). Artificial Intelligence: Structures and Strategies for Complex Problem Solving, 3d ed. Reading, MA: Addison-Wesley.
Russell, Stuart J., and Norvig, Peter. (1995). Artificial Intelligence: A Modern Approach. Upper Saddle River, NJ: Prentice-Hall.
[Article by: JAMES V. HANSEN]
| Hacker Slang: AI |
Abbreviation for ‘Artificial Intelligence’, so common that the full form is almost never written or spoken among hackers.
| Geography Dictionary: artificial intelligence |
The use of computer software in, among others, data collection and processing, analysis, searching for patterns and detecting anomalies, modelling, and problem solving. Applications include genetic algorithms and neural networks.
| Britannica Concise Encyclopedia: artificial intelligence |
For more information on artificial intelligence, visit Britannica.com.
| Philosophy Dictionary: artificial intelligence |
(or AI) The science of making machines that can do the kinds of thing that humans can do. Topics of research have included speech recognition, visual recognition, and the more familiar problem solving and game-playing. Modelling a psychological phenomenon on a computer is a way of showing how the phenomenon is possible in a physical world, and is also a way of bringing out the complexities involved in apparently simple tasks. A central concept in much AI research is that of a representation, with programs designed to construct, adapt, and link representations in the production of intelligent responses. This research has been responsible for a considerable retreat from dogmatic behaviourism, in which the idea of mental manipulations was thought to be unscientific, since it is exactly the storage and manipulation of representations of the world that is demanded in the problems AI approaches. Strong AI is the philosophical thesis that appropriately programmed computers have minds in exactly the same sense that we do. Weak AI is the methodological belief that the best way to explore the mind is to proceed as if this were true, without commenting on the legacies of dualism that lead to discomfort with the strong thesis. See also Chinese room, connectionism, frame problem, Turing test.
| US History Encyclopedia: Artificial Intelligence |
Artificial Intelligence, a branch of computer science that seeks to create a computer system capable of sensing the world around it, understanding conversations, learning, reasoning, and reaching decisions, just as would a human. In 1950 the pioneering British mathematician Alan Turing proposed a test for artificial intelligence in which a human subject tries to talk with an unseen conversant. The tester sends questions to the machine via teletype and reads its answers; if the subject cannot discern whether the conversation is being held with another person or a machine, then the machine is deemed to have artificial intelligence. No machine has come close to passing this test, and it is unlikely that one will in the near future. Researchers, however, have made progress on specific pieces of the artificial intelligence puzzle, and some of their work has had tangible benefits.
One area of progress is the field of expert systems, or computer systems designed to reproduce the knowledge base and decision-making techniques used by experts in a given field. Such a system can train workers and assist in decision making. MYCIN, a program developed in 1976 at Stanford University, suggests possible diagnoses for patients with infectious blood diseases, proposes treatments, and explains its "reasoning" in English. Corporations have used such systems to reduce the labor costs involved in repetitive calculations. A system used by American Express since November 1988 to advise when to deny credit to a customer saves the company millions of dollars annually.
A second area of artificial intelligence research is the field of artificial perception, or computer vision. Computer vision is the ability to recognize patterns in an image and to separate objects from background as quickly as the human brain. In the 1990s military technology initially developed to analyze spy-satellite images found its way into commercial applications, including monitors for assembly lines, digital cameras, and automotive imaging systems. Another pursuit in artificial intelligence research is natural language processing, the ability to interpret and generate human languages. In this area, as in others related to artificial intelligence research, commercial applications have been delayed as improvements in hardware—the computing power of the machines themselves—have not kept pace with the increasing complexity of software.
The field of neural networks seeks to reproduce the architecture of the brain—billions of connected nerve cells—by joining a large number of computer processors through a technique known as parallel processing. Fuzzy systems is a subfield of artificial intelligence research based on the assumption that the world encountered by humans is fraught with approximate, rather than precise, information. Interest in the field has been particularly strong in Japan, where fuzzy systems have been used in disparate applications, from operating subway cars to guiding the sale of securities. Some theorists argue that the technical obstacles to artificial intelligence, while large, are not insurmountable. A number of computer experts, philosophers, and futurists have speculated on the ethical and spiritual challenges facing society when artificially intelligent machines begin to mimic human personality traits, including memory, emotion, and consciousness.
Bibliography
Kurzweil, Ray. The Age of Spiritual Machines. New York: Viking, 1999.
Partridge, Derek. A New Guide to Artificial Intelligence. Norwood, N.J.: Ablex, 1991.
Shapiro, Stuart C., ed. Encyclopedia of Artificial Intelligence. 2d ed. New York: Wiley, 1992.
Turbam, Efraim. Expert Systems and Applied Artificial Intelligence. New York: MacMillan, 1992.
—Vincent Kiernan/A. R.
| Columbia Encyclopedia: artificial intelligence |
In the public eye advances in chess-playing computer programs have become symbolic of progress in AI. In 1948 British mathematician Alan Turing developed a chess algorithm for use with calculating machines—it lost to an amateur player in the one game that it played. Ten years later American mathematician Claude Shannon articulated two chess-playing algorithms: brute force, in which all possible moves and their consequences are calculated as far into the future as possible; and selective mode, in which only the most promising moves and their more immediate consequences are evaluated. In 1988 Hitech, a program developed at Carnegie-Mellon Univ., defeated former U.S. champion Arnold Denker in a four-game match, becoming the first computer to defeat a grandmaster. A year later, Gary Kasparov, the reigning world champion, bested Deep Thought, a program developed by the IBM Corp., in a two-game exhibition. In 1990 the German computer Mephisto-Portrose became the first program to defeat a former world champion; while playing an exhibition of 24 simultaneous games, Anatoly Karpov bested 23 human opponents but lost to the computer. Kasparov in 1996 became the first reigning world champion to lose to a computer in a game played with regulation time controls; the Deep Blue computer, developed by the IBM Corp., won the first game of the match, lost the second, drew the third and fourth, and lost the fifth and sixth. Deep Blue used the brute force approach, evaluating more than 100 billion chess positions each turn while looking six moves ahead; it coupled this with the most efficient chess evaluation software yet developed and an extensive library of chess games it could analyze as part of the decision process. Subsequent matches between Vladimir Kramnik and Deep Fritz (2002, 2006) and Kasparov and Deep Junior (2003) have resulted in two ties and a win for the programs. Unlike Deep Blue, which was a specially designed computer, these more recent computer challengers are chess programs that run on powerful personal computers. Such programs have become an important tool in chess, and are used by chess masters to analyze games and experiment with new moves.
Bibliography
See D. Freedman, Brainmakers: How Scientists Are Moving Beyond Computers to Create a Rival to the Human Brain (1994); D. Gelernter, The Muse in the Machine: Computerizing the Poetry of Human Thought (1994).
| World of the Mind: artificial intelligence |
Igor Alexander
The process of designing machines with abilities modelled on human thought. While this mostly involves writing computer programs with human-like characteristics, it has implications for the design of robots and raises philosophical questions about machine–human comparisons.1. Origins and ambitions
Artificial intelligence may be said to have begun in 1950 when Claude Shannon of the Bell Telephone Laboratories in the United States wrote an ingenious program that was to be the forerunner of all chess-playing machines. This work drastically changed the accepted perception of stored-program computers which, since their birth in 1947, had been seen just as automatic calculating machines. Shannon's program added the promise of automated intelligent action to the actuality of automated calculation.2. Knowledge, logic, and learning
These censures had a healthy effect on AI. The 1980s saw a maturing of the field through the appearance of new methodologies dubbed knowledge-based systems, expert systems, and artificial neural networks (or connectionism). Effort in knowledge-based systems used formal logic to greater effect than before. The application of the logical rules of inheritance and resolution made more efficient use of knowledge stored in databases. For example, 'Socrates is a man' and 'All men are mortals' could lead to the knowledge that 'Socrates is mortal' by logical inference rather than by explicit storage, thus easing the problem of holding vast amounts of data in databases.3. Evolution, agents, and brain–mind comparisons
Despite the above two major phases in the history of artificial intelligence, the subject is still developing, particularly in three domains: new techniques for creating intelligent programs, using computers to understand the complexities of brain and mind, and, finally, contributing to philosophical debate.The techniques added to the AI repertoire are evolutionary programming, artificial life, and intelligent software agents. Evolutionary programming borrows from human genetic development in the sense that some variants of a program may have a better performance than others. It is possible to represent the design parameters of a system as a sequence of values resembling a chromosome. An evolutionary program tests a range of systems against a performance criterion (the fitness function). It chooses the chromosomes of various system pairs that have good fitness behaviour to combine them and create a new generation of systems. This gives rise to increasingly more able systems even to the extent that their design holds surprises for expert designers. Such mimicking of a major mechanism of biological life leads to the concept of artificial life. For example, UK entrepreneur Steve Grand includes in his 'Creatures' game simulations of some biochemical processes to produce societies of virtual (computer-bound but observable) creatures with realistic life cycles and social interactions. This allows the game player to take care of a virtual creature in a game that gets close to the problems of survival in real life. The more general study of intelligent software agents takes virtual creatures into domains where they could perform useful tasks such as finding desired data on the internet. They are little programs that store the needs of a user and trawl the World Wide Web for this desired information. Also a burgeoning interest is in societies of such agents to discover how cooperation between them may lead to the solution of problems in distributed domains. Translated to multiple interacting robots, agent studies lead to a better understanding of flocking behaviour and the way that this achieves goals for the flock.Margaret Boden
The science of making machines do the sorts of things that are done by human minds. Such things include holding a conversation, answering questions sensibly on the basis of incomplete knowledge, assembling another machine from its components given the blueprint, learning how to do things better, playingRon Chrisley
Researchers in artificial intelligence attempt to design and create artefacts which have, or at least appear to have, mental properties: not just intelligences, but also perception, action, emotion, creativity, and consciousness.1. Recent developments
Since the mid-1980s, there has been sustained development of the core ideas of artificial intelligence, e.g. representation, planning, reasoning, natural language processing, machine learning, and perception. In addition, various subfields have emerged, such as research into agents (autonomous, independent systems, whether in hardware or software), distributed or multi-agent systems, coping with uncertainty, affective computing/models of emotion, and ontologies (systems of representing various kinds of entities in the world — achievements that, while new advances, are conceptually and methodologically continuous with the field of artificial intelligence as envisaged at the time of its modern genesis: the Dartmouth conference of 1956.2. The relevance of AI to understanding the mind
Why do AI? Of course, there are technological reasons. But are there scientific reasons? Can AI illuminate our understanding of the mind? The acts involved in bringing natural intelligences into the world do not (usually!) confer any insight into the nature of intelligence; why should one think the acts involved in creating artificial intelligence would be any more enlightening?| Wikipedia: Artificial intelligence |
Artificial Intelligence (AI) is the intelligence of machines and the branch of computer science which aims to create it. Major AI textbooks define the field as "the study and design of intelligent agents,"[1] where an intelligent agent is a system that perceives its environment and takes actions which maximize its chances of success.[2] John McCarthy, who coined the term in 1956,[3] defines it as "the science and engineering of making intelligent machines."[4]
The field was founded on the claim that a central property of human beings, intelligence—the sapience of Homo sapiens—can be so precisely described that it can be simulated by a machine.[5] This raises philosophical issues about the nature of the mind and limits of scientific hubris, issues which have been addressed by myth, fiction and philosophy since antiquity.[6] Artificial intelligence has been the subject of breathtaking optimism,[7] has suffered stunning setbacks[8] and, today, has become an essential part of the technology industry, providing the heavy lifting for many of the most difficult problems in computer science.[9]
AI research is highly technical and specialized, so much so that some critics decry the "fragmentation" of the field.[10] Subfields of AI are organized around particular problems, the application of particular tools and around longstanding theoretical differences of opinion. The central problems of AI include such traits as reasoning, knowledge, planning, learning, communication, perception and the ability to move and manipulate objects.[11] General intelligence (or "strong AI") is still a long-term goal of (some) research[12], while many researchers no longer believe that this is possible.
Contents |
Thinking machines and artificial beings appear in Greek myths, such as Talos of Crete, the golden robots of Hephaestus and Pygmalion's Galatea.[13] Human likenesses believed to have intelligence were built in many ancient societies; some of the earliest being the sacred statues worshipped in Egypt and Greece,[14][15] and including the machines of Yan Shi,[16] Hero of Alexandria,[17] Al-Jazari[18] or Wolfgang von Kempelen.[19] It was widely believed that artificial beings had been created by Jābir ibn Hayyān,[20] Judah Loew[21] and Paracelsus.[22] Stories of these creatures and their fates discuss many of the same hopes, fears and ethical concerns that are presented by artificial intelligence.[6]
Mary Shelley's Frankenstein,[23] considers a key issue in the ethics of artificial intelligence: if a machine can be created that has intelligence, could it also feel? If it can feel, does it have the same rights as a human being? The idea also appears in modern science fiction: the film Artificial Intelligence: A.I. considers a machine in the form of a small boy which has been given the ability to feel human emotions, including, tragically, the capacity to suffer. This issue, now known as "robot rights", is currently being considered by, for example, California's Institute for the Future,[24] although many critics believe that the discussion is premature.[25]
Another issue explored by both science fiction writers and futurists is the impact of artificial intelligence on society. In fiction, AI has appeared as a servant (R2D2 in Star Wars), a law enforcer (K.I.T.T. "Knight Rider"), a comrade (Lt. Commander Data in Star Trek), a conqueror (The Matrix), a dictator (With Folded Hands), an exterminator (Terminator, Battlestar Galactica), an extension to human abilities (Ghost in the Shell) and the saviour of the human race (R. Daneel Olivaw in the Foundation Series). Academic sources have considered such consequences as: a decreased demand for human labor,[26] the enhancement of human ability or experience,[27] and a need for redefinition of human identity and basic values.[28]
Several futurists argue that artificial intelligence will transcend the limits of progress and fundamentally transform humanity. Ray Kurzweil has used Moore's law (which describes the relentless exponential improvement in digital technology with uncanny accuracy) to calculate that desktop computers will have the same processing power as human brains by the year 2029, and that by 2045 artificial intelligence will reach a point where it is able to improve itself at a rate that far exceeds anything conceivable in the past, a scenario that science fiction writer Vernor Vinge named the "technological singularity".[27] Edward Fredkin argues that "artificial intelligence is the next stage in evolution,"[29] an idea first proposed by Samuel Butler's "Darwin among the Machines" (1863), and expanded upon by George Dyson in his book of the same name in 1998. Several futurists and science fiction writers have predicted that human beings and machines will merge in the future into cyborgs that are more capable and powerful than either. This idea, called transhumanism, which has roots in Aldous Huxley and Robert Ettinger, is now associated with robot designer Hans Moravec, cyberneticist Kevin Warwick and inventor Ray Kurzweil.[27] Transhumanism has been illustrated in fiction as well, for example in the manga Ghost in the Shell and the science fiction series Dune. Pamela McCorduck writes that these scenarios are expressions of an ancient human desire to, as she calls it, "forge the gods."[6]
In the middle of the 20th century, a handful of scientists began a new approach to building intelligent machines, based on recent discoveries in neurology, a new mathematical theory of information, an understanding of control and stability called cybernetics, and above all, by the invention of the digital computer, a machine based on the abstract essence of mathematical reasoning.[30]
The field of modern AI research was founded at a conference on the campus of Dartmouth College in the summer of 1956.[31] Those who attended would become the leaders of AI research for many decades, especially John McCarthy, Marvin Minsky, Allen Newell and Herbert Simon, who founded AI laboratories at MIT, CMU and Stanford. They and their students wrote programs that were, to most people, simply astonishing:[32] computers were solving word problems in algebra, proving logical theorems and speaking English.[33] By the middle 60s their research was heavily funded by the U.S. Department of Defense,[34] and they were optimistic about the future of the new field:
These predictions, and many like them, would not come true. They had failed to recognize the difficulty of some of the problems they faced.[37] In 1974, in response to the criticism of England's Sir James Lighthill and ongoing pressure from Congress to fund more productive projects, the U.S. and British governments cut off all undirected, exploratory research in AI. This was the first AI winter.[38]
In the early 80s, AI research was revived by the commercial success of expert systems,[39] a form of AI program that simulated the knowledge and analytical skills of one or more human experts. By 1985 the market for AI had reached more than a billion dollars, and governments around the world poured money back into the field.[40] However, just a few years later, beginning with the collapse of the Lisp Machine market in 1987, AI once again fell into disrepute, and a second, longer lasting AI winter began.[41]
In the 90s and early 21st century, AI achieved its greatest successes, albeit somewhat behind the scenes. Artificial intelligence is used for logistics, data mining, medical diagnosis and many other areas throughout the technology industry.[9] The success was due to several factors: the incredible power of computers today (see Moore's law), a greater emphasis on solving specific subproblems, the creation of new ties between AI and other fields working on similar problems, and above all a new commitment by researchers to solid mathematical methods and rigorous scientific standards.[42]
Artificial intelligence, by claiming to be able to recreate the capabilities of the human mind, is both a challenge and an inspiration for philosophy. Are there limits to how intelligent machines can be? Is there an essential difference between human intelligence and artificial intelligence? Can a machine have a mind and consciousness? A few of the most influential answers to these questions are given below.[43]
In the 21st century, AI research has become highly specialized and technical. It is deeply divided into subfields that often fail to communicate with each other.[10] Subfields have grown up around particular institutions, the work of particular researchers, particular problems (listed below), long standing differences of opinion about how AI should be done (listed as "approaches" below) and the application of widely differing tools (see tools of AI, below).
The problem of simulating (or creating) intelligence has been broken down into a number of specific sub-problems. These consist of particular traits or capabilities that researchers would like an intelligent system to display. The traits described below have received the most attention.[11]
Early AI researchers developed algorithms that imitated the step-by-step reasoning that human beings use when they solve puzzles, play board games or make logical deductions.[53] By the late 80s and 90s, AI research had also developed highly successful methods for dealing with uncertain or incomplete information, employing concepts from probability and economics.[54]
For difficult problems, most of these algorithms can require enormous computational resources — most experience a "combinatorial explosion": the amount of memory or computer time required becomes astronomical when the problem goes beyond a certain size. The search for more efficient problem solving algorithms is a high priority for AI research.[55]
Human beings solve most of their problems using fast, intuitive judgments rather than the conscious, step-by-step deduction that early AI research was able to model.[56] AI has made some progress at imitating this kind of "sub-symbolic" problem solving: embodied approaches emphasize the importance of sensorimotor skills to higher reasoning; neural net research attempts to simulate the structures inside human and animal brains that gives rise to this skill.
Knowledge representation[57] and knowledge engineering[58] are central to AI research. Many of the problems machines are expected to solve will require extensive knowledge about the world. Among the things that AI needs to represent are: objects, properties, categories and relations between objects;[59] situations, events, states and time;[60] causes and effects;[61] knowledge about knowledge (what we know about what other people know);[62] and many other, less well researched domains. A complete representation of "what exists" is an ontology[63] (borrowing a word from traditional philosophy), of which the most general are called upper ontologies.
Among the most difficult problems in knowledge representation are:
Intelligent agents must be able to set goals and achieve them.[70] They need a way to visualize the future (they must have a representation of the state of the world and be able to make predictions about how their actions will change it) and be able to make choices that maximize the utility (or "value") of the available choices.[71]
In some planning problems, the agent can assume that it is the only thing acting on the world and it can be certain what the consequences of its actions may be.[72] However, if this is not true, it must periodically check if the world matches its predictions and it must change its plan as this becomes necessary, requiring the agent to reason under uncertainty.[73]
Multi-agent planning uses the cooperation and competition of many agents to achieve a given goal. Emergent behavior such as this is used by evolutionary algorithms and swarm intelligence.[74]
Machine learning[75] has been central to AI research from the beginning.[76] Unsupervised learning is the ability to find patterns in a stream of input. Supervised learning includes both classification (be able to determine what category something belongs in, after seeing a number of examples of things from several categories) and regression (given a set of numerical input/output examples, discover a continuous function that would generate the outputs from the inputs). In reinforcement learning[77] the agent is rewarded for good responses and punished for bad ones. These can be analyzed in terms of decision theory, using concepts like utility. The mathematical analysis of machine learning algorithms and their performance is a branch of theoretical computer science known as computational learning theory.
Natural language processing[78] gives machines the ability to read and understand the languages that the human beings speak. Many researchers hope that a sufficiently powerful natural language processing system would be able to acquire knowledge on its own, by reading the existing text available over the internet. Some straightforward applications of natural language processing include information retrieval (or text mining) and machine translation.[79]
The field of robotics[80] is closely related to AI. Intelligence is required for robots to be able to handle such tasks as object manipulation[81] and navigation, with sub-problems of localization (knowing where you are), mapping (learning what is around you) and motion planning (figuring out how to get there).[82]
Machine perception[83] is the ability to use input from sensors (such as cameras, microphones, sonar and others more exotic) to deduce aspects of the world. Computer vision[84] is the ability to analyze visual input. A few selected subproblems are speech recognition,[85] facial recognition and object recognition.[86]
Emotion and social skills play two roles for an intelligent agent:[87]
A sub-field of AI addresses creativity both theoretically (from a philosophical and psychological perspective) and practically (via specific implementations of systems that generate outputs that can be considered creative).
Most researchers hope that their work will eventually be incorporated into a machine with general intelligence (known as strong AI), combining all the skills above and exceeding human abilities at most or all of them.[12] A few believe that anthropomorphic features like artificial consciousness or an artificial brain may be required for such a project.[88]
Many of the problems above are considered AI-complete: to solve one problem, you must solve them all. For example, even a straightforward, specific task like machine translation requires that the machine follow the author's argument (reason), know what is being talked about (knowledge), and faithfully reproduce the author's intention (social intelligence). Machine translation, therefore, is believed to be AI-complete: it may require strong AI to be done as well as humans can do it.[89]
There is no established unifying theory or paradigm that guides AI research. Researchers disagree about many issues. A few of the most long standing questions that have remained unanswered are these: Can intelligence be reproduced using high-level symbols, similar to words and ideas? Or does it require "sub-symbolic" processing?[90] Should artificial intelligence simulate natural intelligence, by studying human psychology or animal neurobiology? Or is human biology as irrelevant to AI research as bird biology is to aeronautical engineering?[91] Can intelligent behavior be described using simple, elegant principles (such as logic or optimization)? Or does artificial intelligence necessarily require solving many seemingly unrelated problems?[92]
In the 1940s and 1950s, a number of researchers explored the connection between neurology, information theory, and cybernetics. Some of them built machines that used electronic networks to exhibit rudimentary intelligence, such as W. Grey Walter's turtles and the Johns Hopkins Beast. Many of these researchers gathered for meetings of the Teleological Society at Princeton University and the Ratio Club in England.[30] By 1960, this approach was largely abandoned, although elements of it would be revived in the 1980s.
When access to digital computers became possible in the middle 1950s, AI research began to explore the possibility that human intelligence could be reduced to symbol manipulation. The research was centered in three institutions: CMU, Stanford and MIT, and each one developed its own style of research. John Haugeland named these approaches to AI "good old fashioned AI" or "GOFAI".[93]
During the 1960s, symbolic approaches had achieved great success at simulating high-level thinking in small demonstration programs. Approaches based on cybernetics or neural networks were abandoned or pushed into the background.[102] By the 1980s, however, progress in symbolic AI seemed to stall and many believed that symbolic systems would never be able to imitate all the processes of human cognition, especially perception, robotics, learning and pattern recognition. A number of researchers began to look into "sub-symbolic" approaches to specific AI problems.[90]
In the 1990s, AI researchers developed sophisticated mathematical tools to solve specific subproblems. These tools are truly scientific, in the sense that their results are both measurable and verifiable, and they have been responsible for many of AI's recent successes. The shared mathematical language has also permitted a high level of collaboration with more established fields (like mathematics, economics or operations research). Russell & Norvig (2003) describe this movement as nothing less than a "revolution" and "the victory of the neats."[42]
In the course of 50 years of research, AI has developed a large number of tools to solve the most difficult problems in computer science. A few of the most general of these methods are discussed below.
Many problems in AI can be solved in theory by intelligently searching through many possible solutions:[110] Reasoning can be reduced to performing a search. For example, logical proof can be viewed as searching for a path that leads from premises to conclusions, where each step is the application of an inference rule.[111] Planning algorithms search through trees of goals and subgoals, attempting to find a path to a target goal, a process called means-ends analysis.[112] Robotics algorithms for moving limbs and grasping objects use local searches in configuration space.[81] Many learning algorithms use search algorithms based on optimization.
Simple exhaustive searches[113] are rarely sufficient for most real world problems: the search space (the number of places to search) quickly grows to astronomical numbers. The result is a search that is too slow or never completes. The solution, for many problems, is to use "heuristics" or "rules of thumb" that eliminate choices that are unlikely to lead to the goal (called "pruning the search tree"). Heuristics supply the program with a "best guess" for what path the solution lies on.[114]
A very different kind of search came to prominence in the 1990s, based on the mathematical theory of optimization. For many problems, it is possible to begin the search with some form of a guess and then refine the guess incrementally until no more refinements can be made. These algorithms can be visualized as blind hill climbing: we begin the search at a random point on the landscape, and then, by jumps or steps, we keep moving our guess uphill, until we reach the top. Other optimization algorithms are simulated annealing, beam search and random optimization.[115]
Evolutionary computation uses a form of optimization search. For example, they may begin with a population of organisms (the guesses) and then allow them to mutate and recombine, selecting only the fittest to survive each generation (refining the guesses). Forms of evolutionary computation include swarm intelligence algorithms (such as ant colony or particle swarm optimization)[116] and evolutionary algorithms (such as genetic algorithms[117] and genetic programming[118][119]).
Logic[120] was introduced into AI research by John McCarthy in his 1958 Advice Taker proposal. In 1963, J. Alan Robinson discovered a simple, complete and entirely algorithmic method for logical deduction which can easily be performed by digital computers.[121] However, a naive implementation of the algorithm quickly leads to a combinatorial explosion or an infinite loop. In 1974, Robert Kowalski suggested representing logical expressions as Horn clauses (statements in the form of rules: "if p then q"), which reduced logical deduction to backward chaining or forward chaining. This greatly alleviated (but did not eliminate) the problem.[111][122]
Logic is used for knowledge representation and problem solving, but it can be applied to other problems as well. For example, the satplan algorithm uses logic for planning,[123] and inductive logic programming is a method for learning.[124] There are several different forms of logic used in AI research.
Many problems in AI (in reasoning, planning, learning, perception and robotics) require the agent to operate with incomplete or uncertain information. Starting in the late 80s and early 90s, Judea Pearl and others championed the use of methods drawn from probability theory and economics to devise a number of powerful tools to solve these problems.[128][129]
Bayesian networks[130] are a very general tool that can be used for a large number of problems: reasoning (using the Bayesian inference algorithm),[131] learning (using the expectation-maximization algorithm),[132] planning (using decision networks)[133] and perception (using dynamic Bayesian networks).[134]
Probabilistic algorithms can also be used for filtering, prediction, smoothing and finding explanations for streams of data, helping perception systems to analyze processes that occur over time[135] (e.g., hidden Markov models[136] or Kalman filters[137]).
A key concept from the science of economics is "utility": a measure of how valuable something is to an intelligent agent. Precise mathematical tools have been developed that analyze how an agent can make choices and plan, using decision theory, decision analysis,[138] information value theory.[71] These tools include models such as Markov decision processes,[139] dynamic decision networks,[139] game theory and mechanism design[140]
The simplest AI applications can be divided into two types: classifiers ("if shiny then diamond") and controllers ("if shiny then pick up"). Controllers do however also classify conditions before inferring actions, and therefore classification forms a central part of many AI systems.
Classifiers[141] are functions that use pattern matching to determine a closest match. They can be tuned according to examples, making them very attractive for use in AI. These examples are known as observations or patterns. In supervised learning, each pattern belongs to a certain predefined class. A class can be seen as a decision that has to be made. All the observations combined with their class labels are known as a data set.
When a new observation is received, that observation is classified based on previous experience. A classifier can be trained in various ways; there are many statistical and machine learning approaches.
A wide range of classifiers are available, each with its strengths and weaknesses. Classifier performance depends greatly on the characteristics of the data to be classified. There is no single classifier that works best on all given problems; this is also referred to as the "no free lunch" theorem. Various empirical tests have been performed to compare classifier performance and to find the characteristics of data that determine classifier performance. Determining a suitable classifier for a given problem is however still more an art than science.
The most widely used classifiers are the neural network,[142] kernel methods such as the support vector machine,[143] k-nearest neighbor algorithm,[144] Gaussian mixture model,[145] naive Bayes classifier,[146] and decision tree.[147] The performance of these classifiers have been compared over a wide range of classification tasks[148] in order to find data characteristics that determine classifier performance.
The study of artificial neural networks[142] began in the decade before the field AI research was founded. In the 1960s Frank Rosenblatt developed an important early version, the perceptron.[149] Paul Werbos developed the backpropagation algorithm for multilayer perceptrons in 1974,[150] which led to a renaissance in neural network research and connectionism in general in the middle 1980s. The Hopfield net, a form of attractor network, was first described by John Hopfield in 1982.
Common network architectures which have been developed include the feedforward neural network, the radial basis network, the Kohonen self-organizing map and various recurrent neural networks.[citation needed] Neural networks are applied to the problem of learning, using such techniques as Hebbian learning, competitive learning[151] and the relatively new architectures of Hierarchical Temporal Memory and Deep Belief Networks.
Control theory, the grandchild of cybernetics, has many important applications, especially in robotics.[152]
AI researchers have developed several specialized languages for AI research:
AI applications are also often written in standard languages like C++ and languages designed for mathematics, such as MATLAB and Lush.
How can one determine if an agent is intelligent? In 1950, Alan Turing proposed a general procedure to test the intelligence of an agent now known as the Turing test. This procedure allows almost all the major problems of artificial intelligence to be tested. However, it is a very difficult challenge and at present all agents fail.
Artificial intelligence can also be evaluated on specific problems such as small problems in chemistry, hand-writing recognition and game-playing. Such tests have been termed subject matter expert Turing tests. Smaller problems provide more achievable goals and there are an ever-increasing number of positive results.
The broad classes of outcome for an AI test are:
For example, performance at checkers (draughts) is optimal,[156] performance at chess is super-human and nearing strong super-human,[157] and performance at many everyday tasks performed by humans is sub-human.
There are a number of competitions and prizes to promote research in artificial intelligence. The main areas promoted are: general machine intelligence, conversational behaviour, data-mining, driverless cars, robot soccer and games.
Artificial intelligence has successfully been used in a wide range of fields including medical diagnosis, stock trading, robot control, law, scientific discovery, video games, toys, and Web search engines. Frequently, when a technique reaches mainstream use it is no longer considered artificial intelligence, sometimes described as the AI effect.[158] It may also become integrated into artificial life.
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| Translations: Ai |
Dansk (Danish)
1.
n. - tretået dovendyr
2.
abbr. - kunstig intelligens, AI
Français (French)
1.
n. - (Zool) aï, (Zool) paresseux
2.
abbr. - (abrév = airborne intercept) (Aviat) avion d'interception, interception aéroportée
abbr. - Intelligence artificielle, Insémination artificielle, Amnesty International
Deutsch (German)
n. - Ai, dreizehiges Faultier
abbr. - künstliche Intelligenz/Besamung
Ελληνική (Greek)
abbr. - τεχνητή νοημοσύνη
Italiano (Italian)
inseminazione artificiale, intelligenza artificiale
Português (Portuguese)
abbr. - interceptação (f) aérea (Mil.), inseminação (f) artificial (Med.) (Zool.), inteligência (f) artificial (Inf.)
Русский (Russian)
искусственный разум
Español (Spanish)
1.
n. - mamífero desdentado del norte de Brasil y Venezuela
2.
abbr. - inteligencia artificial
abbr. - inseminación artificial, Amnistía Internacional
Svenska (Swedish)
abbr. - konstgjord intelligens, konstgjord befruktning
中文(简体)(Chinese (Simplified))
1. 三趾树獭
2. 偶然招致的, 遭遇意外, 人工智能, 人工授精, 机载截听
中文(繁體)(Chinese (Traditional))
1.
abbr. - 偶然招致的, 遭遇意外, 人工智慧, 人工授精, 機載截聽
2.
n. - 三趾樹獺
한국어 (Korean)
1.
n. - 세손가락 나무늘보
2.
abbr. - artificial intelligence(인공지능)
العربيه (Arabic)
(اختصار) أختصار معناه : ألذكاء ألإصطناعي, ألإخصاب ألإصطناعي
עברית (Hebrew)
n. - עצלן תלת-האצבע (חיה המצויה בדרום אמריקה)
abbr. - הזרעה מלאכותית, בינה מלאכותית
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Did you mean: artificial intelligence, ai (abbreviation), .ai (abbreviation), Ai (abbreviation)
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