Herbert Alexander Simon (June 15, 1916 – February 9, 2001) was an American economist, political scientist and cognitive psychologist, whose primary research interest was decision-making within organizations and is best known for the theories of "bounded rationality" and "satisficing". He received the Nobel Prize in Economics in 1978 and the Turing Award in 1975. His research was noted for its interdisciplinary nature and spanned across the fields of cognitive science, computer science, public administration, management, and political science. He was at Carnegie Mellon University for most of his career, from 1949 to 2001.
Notably, Simon was among the pioneers of several modern-day scientific domains such as artificial intelligence, information processing, decision-making, problem-solving, organization theory, and complex systems. He was among the earliest to analyze the architecture of complexity and to propose a preferential attachment mechanism to explain power law distributions.
Herbert Alexander Simon
June 15, 1916
|Died||February 9, 2001 (aged 84)|
|Alma mater||University of Chicago|
|Known for||Bounded rationality|
|Spouse(s)||Dorothea Isabel Pye (1939-2001, his death) (1913-2002)|
|Institutions||Carnegie Mellon University|
|Doctoral advisor||Henry Schultz|
|Other academic advisors||Rudolf Carnap|
John R. Commons
|Doctoral students||Edward Feigenbaum|
William F. Pounds
|Influences||Richard T. Ely, John R. Commons, Henry George, Chester Barnard, Charles Merriam|
|Influenced||Daniel Kahneman, Amos Tversky, Gerd Gigerenzer, James March, Allen Newell, Philip E. Tetlock, Richard Thaler, John Muth, Oliver E. Williamson, Massimo Egidi, Vela Velupillai, Ha Joon Chang, William C. Wimsatt, Alok Bhargava, Nassim Nicholas Taleb|
Herbert Alexander Simon was born in Milwaukee, Wisconsin, on June 15, 1916. His father, Arthur Simon (1881–1948), was a Jewish electrical engineer who had come to the United States from Germany in 1903 after earning his engineering degree from the Technische Hochschule of Darmstadt. An inventor who was granted "several dozen patents", his father also was an independent patent attorney. His mother, Edna Marguerite Merkel, was an accomplished pianist whose ancestors had come from Prague and Cologne. His European ancestors had been piano makers, goldsmiths, and vintners. Simon's father was Jewish and his mother came from a family with Jewish, Lutheran, and Catholic backgrounds. Simon called himself an atheist.
Simon was educated in the Milwaukee public school system, where he developed an interest in science. He found schoolwork to be interesting, but rather easy. Unlike many children, Simon was exposed to the idea that human behavior could be studied scientifically at a relatively young age due to the influence of his mother's younger brother, Harold Merkel, who had studied economics at the University of Wisconsin–Madison under John R. Commons. Through his uncle's books on economics and psychology, Simon discovered the social sciences. Among his earliest influences, Simon has cited Richard Ely's economics textbook, Norman Angell's The Great Illusion, and Henry George's Progress and Poverty. At that time, Simon argued "from conviction, rather than cussedness" in favor of George's controversial "single tax" on land rents.
In 1933, Simon entered the University of Chicago, and following those early influences, he studied the social sciences and mathematics. He was interested in biology, but chose not to study it because of his "color-blindness and awkwardness in the laboratory". He chose instead to focus on political science and economics. His most important mentor was Henry Schultz, an econometrician and mathematical economist. Simon received both his B.A. (1936) and his Ph.D. (1943) in political science, from the University of Chicago, where he studied under Harold Lasswell, Nicolas Rashevsky, Rudolf Carnap, Henry Schultz, and Charles Edward Merriam.
After enrolling in a course on "Measuring Municipal Governments", Simon was invited to be a research assistant for Clarence Ridley, with whom he coauthored Measuring Municipal Activities in 1938. Eventually his studies led him to the field of organizational decision-making, which would become the subject of his doctoral dissertation.
After graduating with his undergraduate degree, Simon obtained a research assistantship in municipal administration which turned into a directorship at the University of California, Berkeley.
From 1942 to 1949, Simon was a professor of political science and also served as department chairman at Illinois Institute of Technology in Chicago. There, he began participating in the seminars held by the staff of the Cowles Commission who at that time included Trygve Haavelmo, Jacob Marschak, and Tjalling Koopmans. He thus began an in-depth study of economics in the area of institutionalism. Marschak brought Simon in to assist in the study he was currently undertaking with Sam Schurr of the "prospective economic effects of atomic energy".
From 1949 to 2001, Simon was a faculty at Carnegie Mellon. In 1949, Simon became a professor of administration and chairman of the Department of Industrial Management at Carnegie Tech (later to become Carnegie Mellon University). Simon later also taught psychology and computer science in the same university, (occasionally visiting other universities.).
Seeking to replace the highly simplified classical approach to economic modeling, Simon became best known for his theory of corporate decision in his book Administrative Behavior. In this book he based his concepts with an approach that recognized multiple factors that contribute to decision making. His organization and administration interest allowed him to not only serve three times as a university department chairman, but he also played a big part in the creation of the Economic Cooperation Administration in 1948; administrative team that administered aid to the Marshall Plan for the U.S. government, serving on President Lyndon Johnson's Science Advisory Committee, and also the National Academy of Science. Simon has made a great number of contributions to both economic analysis and applications. Because of this, his work can be found in a number of economic literary works, making contributions to areas such as mathematical economics including theorem, human rationality, behavioral study of firms, theory of casual ordering, and the analysis of the parameter identification problem in econometrics.
Administrative Behavior, first published in 1947, and updated across the years was based on Simon's doctoral dissertation. It served as the foundation for his life's work. The centerpiece of this book is the behavioral and cognitive processes of humans making rational choices, that is, decisions. By his definition, an operational administrative decision should be correct and efficient, and it must be practical to implement with a set of coordinated means.
Simon recognized that a theory of administration is largely a theory of human decision making, and as such must be based on both economics and on psychology. He states:
[If] there were no limits to human rationality administrative theory would be barren. It would consist of the single precept: Always select that alternative, among those available, which will lead to the most complete achievement of your goals. (p xxviii)
Contrary to the "homo economicus" stereotype, Simon argued that alternatives and consequences may be partly known, and means and ends imperfectly differentiated, incompletely related, or poorly detailed.
Simons defined the task of rational decision making is to select the alternative that results in the more preferred set of all the possible consequences. Correctness of administrative decisions was thus measured by:
The task of choice was divided into three required steps:
Any given individual or organization attempting to implement this model in a real situation would be unable to comply with the three requirements. Simon argued that knowledge of all alternatives, or all consequences that follow from each alternative is impossible in many realistic cases.
Simon attempted to determine the techniques and/or behavioral processes that a person or organization could bring to bear to achieve approximately the best result given limits on rational decision making. Simon writes:
The human being striving for rationality and restricted within the limits of his knowledge has developed some working procedures that partially overcome these difficulties. These procedures consist in assuming that he can isolate from the rest of the world a closed system containing a limited number of variables and a limited range of consequences.
Simon therefore, describes work in terms of an economic framework, conditioned on human cognitive limitations: Economic man and Administrative man.
Administrative Behavior addresses a wide range of human behaviors, cognitive abilities, management techniques, personnel policies, training goals and procedures, specialized roles, criteria for evaluation of accuracy and efficiency, and all of the ramifications of communication processes. Simon is particularly interested in how these factors influence the making of decisions, both directly and indirectly.
Simons argued that the two outcomes of a choice require monitoring and that many members of the organization would be expected to focus on adequacy, but that administrative management must pay particular attention to the efficiency with which the desired result was obtained.
Simon followed Chester Barnard who pointed out that "the decisions that an individual makes as a member of an organization are quite distinct from his personal decisions". Personal choices may be determined whether an individual joins a particular organization, and continue to be made in his or her extra–organizational private life. As a member of an organization, however, that individual makes decisions not in relationship to personal needs and results, but in an impersonal sense as part of the organizational intent, purpose, and effect. Organizational inducements, rewards, and sanctions are all designed to form, strengthen, and maintain this identification.
Simon saw two universal elements of human social behavior as key to creating the possibility of organizational behavior in human individuals: Authority (addressed in Chapter VII—The Role of Authority) and in Loyalties and Identification (Addressed in Chapter X: Loyalties, and Organizational Identification).
Authority is a well-studied, primary mark of organizational behavior, straightforwardly defined in the organizational context as the ability and right of an individual of higher rank to guide the decisions of an individual of lower rank. The actions, attitudes, and relationships of the dominant and subordinate individuals constitute components of role behavior that may vary widely in form, style, and content, but do not vary in the expectation of obedience by the one of superior status, and willingness to obey from the subordinate.
Loyalty was defined by Simon as the "process whereby the individual substitutes organizational objectives (service objectives or conservation objectives) for his own aims as the value-indices which determine his organizational decisions". This entailed evaluating alternative choices in terms of their consequences for the group rather than only for onself or ones family.
Decisions can be complex admixtures of facts and values. Information about facts, especially empirically-proven facts or facts derived from specialized experience, are more easily transmitted in the exercise of authority than are the expressions of values. Simon is primarily interested in seeking identification of the individual employee with the organizational goals and values. Following Lasswell, he states that "a person identifies himself with a group when, in making a decision, he evaluates the several alternatives of choice in terms of their consequences for the specified group". A person may identify himself with any number of social, geographic, economic, racial, religious, familial, educational, gender, political, and sports groups. Indeed, the number and variety are unlimited. The fundamental problem for organizations is to recognize that personal and group identifications may either facilitate or obstruct correct decision making for the organization. A specific organization has to determine deliberately, and specify in appropriate detail and clear language, its own goals, objectives, means, ends, and values.
Simon has been critical of traditional economics' elementary understanding of decision-making, and argues it "is too quick to build an idealistic, unrealistic picture of the decision-making process and then prescribe on the basis of such unrealistic picture". His contributions to research in the area of administrative decision-making have become increasingly mainstream in the business community.
Simon was a pioneer in the field of artificial intelligence, creating with Allen Newell the Logic Theory Machine (1956) and the General Problem Solver (GPS) (1957) programs. GPS may possibly be the first method developed for separating problem solving strategy from information about particular problems. Both programs were developed using the Information Processing Language (IPL) (1956) developed by Newell, Cliff Shaw, and Simon. Donald Knuth mentions the development of list processing in IPL, with the linked list originally called "NSS memory" for its inventors. In 1957, Simon predicted that computer chess would surpass human chess abilities within "ten years" when, in reality, that transition took about forty years.
In the early 1960s psychologist Ulric Neisser asserted that while machines are capable of replicating "cold cognition" behaviors such as reasoning, planning, perceiving, and deciding, they would never be able to replicate "hot cognition" behaviors such as pain, pleasure, desire, and other emotions. Simon responded to Neisser's views in 1963 by writing a paper on emotional cognition, which he updated in 1967 and published in Psychological Review. Simon's work on emotional cognition was largely ignored by the artificial intelligence research community for several years, but subsequent work on emotions by Sloman and Picard helped refocus attention on Simon's paper and eventually, made it highly influential on the topic.
With Allen Newell, Simon developed a theory for the simulation of human problem solving behavior using production rules. The study of human problem solving required new kinds of human measurements and, with Anders Ericsson, Simon developed the experimental technique of verbal protocol analysis. Simon was interested in the role of knowledge in expertise. He said that to become an expert on a topic required about ten years of experience and he and colleagues estimated that expertise was the result of learning roughly 50,000 chunks of information. A chess expert was said to have learned about 50,000 chunks or chess position patterns.
He was awarded the ACM Turing Award, along with Allen Newell, in 1975. "In joint scientific efforts extending over twenty years, initially in collaboration with J. C. (Cliff) Shaw at the RAND Corporation, and subsequentially [sic] with numerous faculty and student colleagues at Carnegie Mellon University, they have made basic contributions to artificial intelligence, the psychology of human cognition, and list processing."
Simon was interested in how humans learn and, with Edward Feigenbaum, he developed the EPAM (Elementary Perceiver and Memorizer) theory, one of the first theories of learning to be implemented as a computer program. EPAM was able to explain a large number of phenomena in the field of verbal learning. Later versions of the model were applied to concept formation and the acquisition of expertise. With Fernand Gobet, he has expanded the EPAM theory into the CHREST computational model. The theory explains how simple chunks of information form the building blocks of schemata, which are more complex structures. CHREST has been used predominantly, to simulate aspects of chess expertise.
Simon has been credited for revolutionary changes in microeconomics. He is responsible for the concept of organizational decision-making as it is known today. He also was the first to discuss this concept in terms of uncertainty; i.e., it is impossible to have perfect and complete information at any given time to make a decision. While this notion was not entirely new, Simon is best known for its origination. It was in this area that he was awarded the Nobel Prize in 1978.
At the Cowles Commission, Simon's main goal was to link economic theory to mathematics and statistics. His main contributions were to the fields of general equilibrium and econometrics. He was greatly influenced by the marginalist debate that began in the 1930s. The popular work of the time argued that it was not apparent empirically that entrepreneurs needed to follow the marginalist principles of profit-maximization/cost-minimization in running organizations. The argument went on to note that profit maximization was not accomplished, in part, because of the lack of complete information. In decision-making, Simon believed that agents face uncertainty about the future and costs in acquiring information in the present. These factors limit the extent to which agents may make a fully rational decision, thus they possess only "bounded rationality" and must make decisions by "satisficing", or choosing that which might not be optimal, but which will make them happy enough. Bounded rationality is a central theme in behavioral economics. It is concerned with the ways in which the actual decision making process influences decision. Theories of bounded rationality relax one or more assumptions of standard expected utility theory.
Further, Simon emphasized that psychologists invoke a "procedural" definition of rationality, whereas economists employ a "substantive" definition. Gustavos Barros argued that the procedural rationality concept does not have a significant presence in the economics field and has never had nearly as much weight as the concept of bounded rationality. However, in an earlier article, Bhargava (1997) noted the importance of Simon's arguments and emphasized that there are several applications of the "procedural" definition of rationality in econometric analyses of data on health. In particular, economists should employ "auxiliary assumptions" that reflect the knowledge in the relevant biomedical fields, and guide the specification of econometric models for health outcomes.
Simon was also known for his research on industrial organization. He determined that the internal organization of firms and the external business decisions thereof, did not conform to the neoclassical theories of "rational" decision-making. Simon wrote many articles on the topic over the course of his life, mainly focusing on the issue of decision-making within the behavior of what he termed "bounded rationality". "Rational behavior, in economics, means that individuals maximize their utility function under the constraints they face (e.g., their budget constraint, limited choices, ...) in pursuit of their self-interest. This is reflected in the theory of subjective expected utility. The term, bounded rationality, is used to designate rational choice that takes into account the cognitive limitations of both knowledge and cognitive capacity. Bounded rationality is a central theme in behavioral economics. It is concerned with the ways in which the actual decision-making process influences decisions. Theories of bounded rationality relax one or more assumptions of standard expected utility theory".
Simon determined that the best way to study these areas was through computer simulations. As such, he developed an interest in computer science. Simon's main interests in computer science were in artificial intelligence, human–computer interaction, principles of the organization of humans and machines as information processing systems, the use of computers to study (by modeling) philosophical problems of the nature of intelligence and of epistemology, and the social implications of computer technology.
In his youth, Simon took an interest in land economics and Georgism, an idea known at the time as "single tax". The system is meant to redistribute unearned economic rent to the public and improve land use. In 1979, Simon still maintained these ideas and argued that land value tax should replace taxes on wages.
Some of Simon's economic research was directed toward understanding technological change in general and the information processing revolution in particular.
Simon's work has strongly influenced John Mighton, developer of a program that has achieved significant success in improving mathematics performance among elementary and high school students. Mighton cites a 2000 paper by Simon and two coauthors that counters arguments by French mathematics educator, Guy Brousseau, and others suggesting that excessive practice hampers children's understanding:
[The] criticism of practice (called "drill and kill," as if this phrase constituted empirical evaluation) is prominent in constructivist writings. Nothing flies more in the face of the last 20 years of research than the assertion that practice is bad. All evidence, from the laboratory and from extensive case studies of professionals, indicates that real competence only comes with extensive practice... In denying the critical role of practice one is denying children the very thing they need to achieve real competence. The instructional task is not to "kill" motivation by demanding drill, but to find tasks that provide practice while at the same time sustaining interest.— John R. Anderson, Lynne M. Reder, and Herbert A. Simon, "Applications and misapplications
of cognitive psychology to mathematics education", Texas Educational Review 6 (2000)
He received many top-level honors in life, including becoming a fellow of the American Academy of Arts and Sciences in 1959; election as a Member of the National Academy of Sciences in 1967; APA Award for Distinguished Scientific Contributions to Psychology (1969); the ACM's Turing Award for making "basic contributions to artificial intelligence, the psychology of human cognition, and list processing" (1975); the Nobel Memorial Prize in Economics "for his pioneering research into the decision-making process within economic organizations" (1978); the National Medal of Science (1986); the APA's Award for Outstanding Lifetime Contributions to Psychology (1993); ACM fellow (1994); and IJCAI Award for Research Excellence (1995).
Simon was a prolific writer and authored 27 books and almost a thousand papers. As of 2016, Simon was the most cited person in artificial intelligence and cognitive psychology on Google Scholar. With almost a thousand highly cited publications, he was one of the most influential social scientists of the twentieth century.
Simon married Dorothea Pye in 1938. Their marriage lasted 63 years until his death. In January 2001, Simon underwent surgery at UPMC Presbyterian to remove a cancerous tumor in his abdomen. Although the surgery was successful, Simon later succumbed to the complications that followed. They had three children, Katherine, Peter, and Barbara. His wife died in 2002.
From 1950 to 1955, Simon studied mathematical economics and during this time, together with David Hawkins, discovered and proved the Hawkins–Simon theorem on the "conditions for the existence of positive solution vectors for input-output matrices". He also developed theorems on near-decomposability and aggregation. Having begun to apply these theorems to organizations, by 1954 Simon determined that the best way to study problem-solving was to simulate it with computer programs, which led to his interest in computer simulation of human cognition. Founded during the 1950s, he was among the first members of the Society for General Systems Research.
Simon had a keen interest in the arts, as he was a pianist. He was a friend of Robert Lepper and Richard Rappaport. Rappaport also painted Simon's commissioned portrait at Carnegie Mellon University. He was also a keen mountain climber. As a testament to his wide interests, he at one point taught an undergraduate course on the French Revolution.
Studies and models of decision-making are the themes that unify most of Simon's contributions.
His secular, scientific values came well before he was old enough to make such calculating career decisions. For example, while still in middle school, Simon wrote a letter to the editor of the Milwaukee Journal defending the civil liberties of atheists, and by high school he was "certain" that he was "religiously an atheist", a conviction that never wavered.
James E. Meade
| Laureate of the Nobel Memorial Prize in Economics
Theodore W. Schultz
Sir Arthur Lewis
Allen Newell (March 19, 1927 – July 19, 1992) was a researcher in computer science and cognitive psychology at the RAND Corporation and at Carnegie Mellon University’s School of Computer Science, Tepper School of Business, and Department of Psychology. He contributed to the Information Processing Language (1956) and two of the earliest AI programs, the Logic Theory Machine (1956) and the General Problem Solver (1957) (with Herbert A. Simon). He was awarded the ACM's A.M. Turing Award along with Herbert A. Simon in 1975 for their basic contributions to artificial intelligence and the psychology of human cognition.Artificiality
Artificiality (also called factitiousness, or the state of being artificial or man-made) is the state of being the product of intentional human manufacture, rather than occurring naturally through processes not involving or requiring human activity.Bounded rationality
Bounded rationality is the idea that rationality is limited when individuals make decisions: by the tractability of the decision problem, the cognitive limitations of the mind, and the time available to make the decision. Decision-makers, in this view, act as satisficers, seeking a satisfactory solution rather than an optimal one.
Herbert A. Simon proposed bounded rationality as an alternative basis for the mathematical modeling of decision-making, as used in economics, political science and related disciplines. It complements "rationality as optimization", which views decision-making as a fully rational process of finding an optimal choice given the information available. Simon used the analogy of a pair of scissors, where one blade represents "cognitive limitations" of actual humans and the other the "structures of the environment", illustrating how minds compensate for limited resources by exploiting known structural regularity in the environment. Many economics models assume that people are on average rational, and can in large enough quantities be approximated to act according to their preferences. The concept of bounded rationality revises this assumption to account for the fact that perfectly rational decisions are often not feasible in practice because of the intractability of natural decision problems and the finite computational resources available for making them.
Some models of human behavior in the social sciences assume that humans can be reasonably approximated or described as "rational" entities, as in rational choice theory or Downs Political Agency Models.Carnegie Learning
Carnegie Learning, Inc. is a provider of curricula, textbooks
, and math learning software for grades 6-12 written and designed to align to a Common Core or Integrated pathway. Its software was created by researchers in artificial intelligence from Carnegie Mellon University, led by Herbert A. Simon.
Carnegie Learning, Inc. is located in the Union Trust Building in Pittsburgh, PA.Carnegie School
The Carnegie School was a so-called "Freshwater" economics intellectual movement in the 1950s and 1960s based at Carnegie Mellon University and led by Herbert A. Simon, James March, and Richard Cyert.Cliff Shaw
John Clifford Shaw (February 23, 1922 – February 9, 1991) was a systems programmer at the RAND Corporation. He is a coauthor of the first artificial intelligence program, the Logic Theorist, and was one of the developers of Information Processing Language, a programming language of the 1950s. It is considered the true "father" of the JOSS language. One of the most significant events that occurred in the programming was the development of the concept of list processing by Allen Newell, Herbert A. Simon and Cliff Shaw during the development of the language IPL-V. He invented the linked list, which remains fundamental in many strands of modern computing technology.Cowles Foundation
The Cowles Foundation for Research in Economics is an economic research institute at Yale University. It was created as the Cowles Commission for Research in Economics at Colorado Springs in 1932 by businessman and economist Alfred Cowles. In 1939, the Cowles Commission moved to the University of Chicago under Theodore O. Yntema. Jacob Marschak directed it from 1943 until 1948, when Tjalling C. Koopmans assumed leadership. Increasing opposition to the Cowles Commission from the department of economics of the University of Chicago during the 1950s impelled Koopmans to persuade the Cowles family to move the commission to Yale University in 1955 where it became the Cowles Foundation.As its motto Theory and Measurement implies, the Cowles Commission focuses on linking economic theory to mathematics and statistics. Its advances in economics involved the creation and integration of general equilibrium theory and econometrics.
The thrust of the Cowles approach was a specific, probabilistic framework in estimating simultaneous equations to model an economy. Its ultimate goal in doing so was to gain policy insight. The Cowles approach structured its models from a priori economic theory. One of its main contributions was in exposing the bias of ordinary least squares regression in identifying coefficient estimates. Consequently, Cowles researchers developed new methods such as the indirect least squares, instrumental variable methods, the full information maximum likelihood method, and the limited information maximum likelihood method. All of these methods used theoretical, a priori restrictions. According to an article by Carl F. Christ, the Cowles approach was grounded on certain assumptions:
1. simultaneous economic behavior;
2. linear or logarithmic equations and disturbances;
3. systematic, observable variables without error;
4. discrete variable changes as opposed to continuous;
5. a priori determination of exogeneity and endogeneity;
6. the existence of a reduced form;
7. independence of the explanatory variables;
8. a priori identified structural equations;
9. normally distributed disturbances with zero means, finite and constant covariances, a nonsingular covariance matrix, and serial independence;
10. a dynamically stable system of equations.Several Cowles associates have won Nobel prizes for research done while at the Cowles Commission. These include Tjalling Koopmans, Kenneth Arrow, Gérard Debreu, James Tobin, Franco Modigliani, Herbert A. Simon, Joseph E. Stiglitz, Lawrence Klein, Trygve Haavelmo, Leonid Hurwicz and Harry Markowitz.
The Cowles Foundation is located at 30 Hillhouse Avenue, New Haven, Connecticut.David Hawkins (philosopher)
David Hawkins (February 28, 1913 – February 24, 2002) was a professor whose interests included the philosophy of science, mathematics, economics, childhood science education, and ethics. He also served as an administrative assistant at Manhattan Project's Los Alamos Laboratory, and later as one of its official historians. Together with Herbert A. Simon, he discovered and proved the Hawkins–Simon theorem.General Problem Solver
General Problem Solver or G.P.S. is a computer program created in 1959 by Herbert A. Simon, J. C. Shaw, and Allen Newell intended to work as a universal problem solver machine. Any problem that can be expressed as a set of well-formed formulas (WFFs) or Horn clauses, and that constitute a directed graph with one or more sources (viz., axioms) and sinks (viz., desired conclusions), can be solved, in principle, by GPS. Proofs in the predicate logic and Euclidean geometry problem spaces are prime examples of the domain the applicability of GPS. It was based on Simon and Newell's theoretical work on logic machines. GPS was the first computer program which separated its knowledge of problems (rules represented as input data) from its strategy of how to solve problems (a generic solver engine). GPS was implemented in the third-order programming language, IPL.
While GPS solved simple problems such as the Towers of Hanoi that could be sufficiently formalized, it could not solve any real-world problems because search was easily lost in the combinatorial explosion. Put another way, the number of "walks" through the inferential digraph became computationally untenable. (In practice, even a straightforward state space search such as the Towers of Hanoi can become computationally infeasible, albeit judicious prunings of the state space can be achieved by such elementary AI techniques as A* and IDA*).
The user defined objects and operations that could be done on the objects, and GPS generated heuristics by means-ends analysis in order to solve problems. It focused on the available operations, finding what inputs were acceptable and what outputs were generated. It then created subgoals to get closer and closer to the goal.
The GPS paradigm eventually evolved into the Soar architecture for artificial intelligence.Herbert Simon
Herbert Simon may refer to:
Herbert A. Simon (1916–2001), American political scientist and economist
Herbert Simon (real estate) (born 1934), American real estate developerInformation Processing Language
Information Processing Language (IPL) is a programming language created by Allen Newell, Cliff Shaw, and Herbert A. Simon at RAND Corporation and the Carnegie Institute of Technology at about 1956. Newell had the job of language specifier-application programmer, Shaw was the system programmer, and Simon took the job of application programmer-user.
The language includes features intended to help with programs that perform simple problem solving actions such as lists, dynamic memory allocation, data types, recursion, functions as arguments, generators, and cooperative multitasking. IPL invented the concept of list processing, albeit in an assembly-language style.Madeira Interactive Technologies Institute
The Madeira Interactive Technologies Institute (M-ITI) was conceived in 2000, formally integrated as a research group in 2007, and established as an Innovation Institute in 2010.
It resulted from a collaborative connection between the University of Madeira, Madeira Tecnopolo, and Carnegie Mellon University. M-ITI has also been a member of the National Associated Laboratory for Robotics and Systems in Engineering and Science (LARSyS) since 2011.
M-ITI operates in the interdisciplinary domain of Human-Computer Interaction (HCI), and contributions from the disciplines of Computer Sciences, Psychology and Social Sciences, and Design. It has a partnership with the Human-Computer Interaction Institute (HCII) at Carnegie Mellon University (USA), which was founded by computer science pioneers Allen Newell (Turing Award) and Herbert A. Simon (Turing Award and Nobel Prize in Economics). The HCII at Carnegie Mellon is recognized as a worldwide leader in HCI research. M-ITI grew through this collaboration, which was made possible by the Carnegie Mellon | Portugal International Partnership, an initiative conducted by the Portuguese national government that supports collaborative teaching and research between universities in Portugal and Carnegie Mellon University.Manuela M. Veloso
Manuela Maria Veloso (born August 12, 1957), is the Head of the Machine Learning Department at Carnegie Mellon University & Herbert A. Simon University Professor in the School of Computer Science at Carnegie Mellon University. She served as president of Association for the Advancement of Artificial Intelligence (AAAI) until 2014, and the co-founder and a Past President of the RoboCup Federation. She is a fellow of AAAI, Institute of Electrical and Electronics Engineers (IEEE), American Association for the Advancement of Science (AAAS), and Association for Computing Machinery (ACM). She is an international expert in artificial intelligence and robotics.In May 2018 she was hired by JPMorgan Chase as to head its artificial intelligence research.Physical symbol system
A physical symbol system (also called a formal system) takes physical patterns (symbols), combining them into structures (expressions) and manipulating them (using processes) to produce new expressions.
The physical symbol system hypothesis (PSSH) is a position in the philosophy of artificial intelligence formulated by Allen Newell and Herbert A. Simon. They wrote:
"A physical symbol system has the necessary and sufficient means for general intelligent action."
This claim implies both that human thinking is a kind of symbol manipulation (because a symbol system is necessary for intelligence) and that machines can be intelligent (because a symbol system is sufficient for intelligence).The idea has philosophical roots in Hobbes (who claimed reasoning was "nothing more than reckoning"), Leibniz (who attempted to create a logical calculus of all human ideas), Hume (who thought perception could be reduced to "atomic impressions") and even Kant (who analyzed all experience as controlled by formal rules). The latest version is called the computational theory of mind, associated with philosophers Hilary Putnam and Jerry Fodor.The hypothesis has been criticized strongly by various parties, but is a core part of AI research. A common critical view is that the hypothesis seems appropriate for higher-level intelligence such as playing chess, but less appropriate for commonplace intelligence such as vision. A distinction is usually made between the kind of high level symbols that directly correspond with objects in the world, such as
Satisficing is a decision-making strategy or cognitive heuristic that entails searching through the available alternatives until an acceptability threshold is met. The term satisficing, a portmanteau of satisfy and suffice, was introduced by Herbert A. Simon in 1956, although the concept was first posited in his 1947 book Administrative Behavior. Simon used satisficing to explain the behavior of decision makers under circumstances in which an optimal solution cannot be determined. He maintained that many natural problems are characterized by computational intractability or a lack of information, both of which preclude the use of mathematical optimization procedures. He observed in his Nobel Prize in Economics speech that "decision makers can satisfice either by finding optimum solutions for a simplified world, or by finding satisfactory solutions for a more realistic world. Neither approach, in general, dominates the other, and both have continued to co-exist in the world of management science".Simon formulated the concept within a novel approach to rationality, which posits that rational choice theory is an unrealistic description of human decision processes and calls for psychological realism. He referred to this approach as bounded rationality. Some consequentialist theories in moral philosophy use the concept of satisficing in the same sense, though most call for optimization instead.Simplicity
Simplicity is the state or quality of being simple. Something easy to understand or explain seems simple, in contrast to something complicated. Alternatively, as Herbert A. Simon suggests, something is simple or complex depending on the way we choose to describe it. In some uses, the label "simplicity" can imply beauty, purity, or clarity. In other cases, the term may occur with negative connotations to suggest, a deficit or insufficiency of nuance or of complexity of a thing, relative to what one supposes as required.
The concept of simplicity has been related to in the field of epistemology and philosophy of science (e.g., in Occam's razor). Religions also reflect on simplicity with concepts such as divine simplicity. In the context of human lifestyle, simplicity can denote freedom from excessive possessions and psychological distractions, specifically, it can refer to a simple living style.Symbolic artificial intelligence
Symbolic artificial intelligence is the term for the collection of all methods in artificial intelligence research that are based on high-level "symbolic" (human-readable) representations of problems, logic and search. Symbolic AI was the dominant paradigm of AI research from the mid-1950s until the late 1980s.John Haugeland gave the name GOFAI ("Good Old-Fashioned Artificial Intelligence") to symbolic AI in his 1985 book Artificial Intelligence: The Very Idea, which explored the philosophical implications of artificial intelligence research. In robotics the analogous term is GOFR ("Good Old-Fashioned Robotics").
The approach is based on the assumption that many aspects of intelligence can be achieved by the manipulation of symbols, an assumption defined as the "physical symbol systems hypothesis" by Allen Newell and Herbert A. Simon in the middle 1960s.
One popular form of symbolic AI is expert systems, which uses a network of production rules. Production rules connect symbols in a relationship similar to an If-Then statement. The expert system processes the rules to make deductions and to determine what additional information it needs, i.e. what questions to ask, using human-readable symbols.
Opponents of the symbolic approach include roboticists such as Rodney Brooks, who aims to produce autonomous robots without symbolic representation (or with only minimal representation) and computational intelligence researchers, who apply techniques such as neural networks and optimization to solve problems in machine learning and control engineering.
Symbolic AI was intended to produce general, human-like intelligence in a machine, whereas most modern research is directed at specific sub-problems. Research into general intelligence is now studied in the sub-field of artificial general intelligence.
Machines were initially designed to formulate outputs based on the inputs that were represented by symbols. Symbols are used when the input is definite and falls under certainty. But when there is uncertainty involved, for example in formulating predictions, the representation is done using "fuzzy logic". This can be seen in artificial neural networks.Tepper School of Business
The Tepper School of Business is the business school of Carnegie Mellon University. It is located in the university’s 140-acre (0.57 km2) campus in Pittsburgh, Pennsylvania, US.
The school offers degrees from the undergraduate through doctoral levels, in addition to executive education programs.
The Tepper School of Business was originally known as the Graduate School of Industrial Administration (GSIA), which was founded in 1949 by William Larimer Mellon. In March 2004, the school received a record $55 million gift from alumnus David Tepper and was renamed the "David A. Tepper School of Business at Carnegie Mellon".
A number of Nobel Prize–winning economists have been affiliated with the school, including Herbert A. Simon, Franco Modigliani, Merton Miller, Robert Lucas, Edward Prescott, Finn Kydland, Oliver Williamson, Dale Mortensen, and Lars Peter Hansen.Yule–Simon distribution
In probability and statistics, the Yule–Simon distribution is a discrete probability distribution named after Udny Yule and Herbert A. Simon. Simon originally called it the Yule distribution.
The probability mass function (pmf) of the Yule–Simon (ρ) distribution is
for integer and real , where is the beta function. Equivalently the pmf can be written in terms of the falling factorial as
where is the gamma function. Thus, if is an integer,
The parameter can be estimated using a fixed point algorithm.
The probability mass function f has the property that for sufficiently large k we have
This means that the tail of the Yule–Simon distribution is a realization of Zipf's law: can be used to model, for example, the relative frequency of the th most frequent word in a large collection of text, which according to Zipf's law is inversely proportional to a (typically small) power of .
A. M. Turing Award laureates
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