Thomas L. Saaty

Bio: Thomas L. Saaty is an academic researcher from University of Pittsburgh. The author has contributed to research in topics: Analytic hierarchy process & Analytic network process. The author has an hindex of 92, co-authored 375 publications receiving 95026 citations. Previous affiliations of Thomas L. Saaty include College of Business Administration & Politécnico Grancolombiano.

The Analytic Hierarchy and Analytic Network Measurement Processes: The Measurement of Intangibles Decision Making under Benefits, Opportunities, Costs and Risks

Abstract: Multicriteria thinking demonstrates that in order to make a best choice in a decision, discussion and cause-effect reasoning are inadequate to learn what the best overall outcome is. The Analytic Hierarchy Process (AHP) and its generaliza- tion to dependence and feedback, the Analytic Network Process (ANP), provide a comprehensive structure and mathematics to incorporate measurements for tangible criteria and derive priorities for intangible criteria to enable one to choose a best al- ternative for a decision. It overcomes so-called bounded rationality that is based on the assumption of transitivity by including in its structures and calculations, the sen- sitivity and depth of feelings associated with understanding and the imagination and awareness needed to address all the concerns. The AHP can cope with the inherent subjectivity in all decision making, and make it explicit to the stakeholders through relative quantitative priorities. It also provides the means to validate outcomes when measurements are available to show that it does not do number crunching without meaningful justification. It can deal with the benefits, opportunities, costs and risks separately and bring them together to determine the best overall outcome. One can also perform dynamic sensitivity analysis of changes in judgments to ensure that the best outcome is stable. In an award from the Institute for Operations Research and the Management Sci- ences (INFORMS) given to the author in October 2008 it is written: "The AHP has revolutionized how we resolve complex decision problems ... the AHP has been applied worldwide to help decision makers in every conceivable decision context across both the public and private sectors, with literally thousands of reported appli- cations."

Reflections and Projections on Creativity in Operations Research and Management Science: a Pressing Need for a Shift in Paradigm

Abstract: This paper is an outgrowth of a talk given at a plenary session of the national meeting of ORSA/TIMS (now INFORMS) in May of 1996. Rather than speculate on what might be the possible domain of OR/MS within a systems framework, the paper gives a sketch of what basic ideas there are today that can help us get to a unified mathematical theory of the subject. The concept of influence occurs in all fields of knowledge-from physics, with its gravitational and electromagnetic influences, to sociology with its societal, political, economic, and technological influences. We argue that influence, a sensed, perceived or inferred stimulus, is the single most central concept for analyzing causal relations in OR/MS problems. Problem solving is contextual and focuses on the distribution of influence in allocation, queuing, inventory, and similar problems by manipulating measurable quantities. Because most influences are abstract and intangible, emphasis on creating structures to represent and measure the flow of influence of intangibles and their propagation is critical for the development of a general scientific theory for OR/MS, more critical than in any other field because our problem domain is very general and interdisciplinary. The paper advocates the need for a systemic integration of the diverse approaches used in OR/MS within a single framework for all areas, including dependencies and feedback among influences to maintain the full integrity of the problems we solve. Examples and illustrations are given together with observations about the use of creativity and intelligence to move the process of creating a theory beyond the traditional process of problem solving.

Coefficient Perturbation of a Constrained Extremum

Abstract: A schedule of allocating labor (in a shipping operation) whose available amount is a function of time, to different tasks, in order to minimize the total cost, is given. The problem is cast in linear-programming form in which all the coefficients are parameterized. An illustration is given followed by a general discussion of the use and limitation of this method, which yields a correspondence between optimal solutions and ranges of time values. The dependence of the optimal value on the parameterized coefficients leads to a sensitivity study.

Ratio Scales Derived from Perturbations of Consistent Judgments

Abstract: We derive ratio scales from paired comparison judgments in a reciprocal matrix A When the judgments are consistent, we have a principal eigenvalue structure which is preserved when A is perturbed Mathematical conditions are given on the size of the perturbations to produce a good approximation to A by a matrix W of ratios formed from the derived scale Goodness is analyzed for both metric and order properties The results of this paper point strongly to the fact that the eigenvalue process is the intrinsic solution to the problem of deriving a ratio scale, thus one does not need to invent extraneous normative criteria to solve an inconsistent problem

The Analytic Hierarchy Process

Abstract: This chapter provides an overview of Analytic Hierarchy Process (AHP), which is a systematic procedure for representing the elements of any problem hierarchically. It organizes the basic rationality by breaking down a problem into its smaller constituent parts and then guides decision makers through a series of pair-wise comparison judgments to express the relative strength or intensity of impact of the elements in the hierarchy. These judgments are then translated to numbers. The AHP includes procedures and principles used to synthesize the many judgments to derive priorities among criteria and subsequently for alternative solutions. It is useful to note that the numbers thus obtained are ratio scale estimates and correspond to so-called hard numbers. Problem solving is a process of setting priorities in steps. One step decides on the most important elements of a problem, another on how best to repair, replace, test, and evaluate the elements, and another on how to implement the solution and measure performance.

Fuzzy Set Theory - and Its Applications

Abstract: Fuzzy Set Theory - And Its Applications, Third Edition is a textbook for courses in fuzzy set theory. It can also be used as an introduction to the subject. The character of a textbook is balanced with the dynamic nature of the research in the field by including many useful references to develop a deeper understanding among interested readers. The book updates the research agenda (which has witnessed profound and startling advances since its inception some 30 years ago) with chapters on possibility theory, fuzzy logic and approximate reasoning, expert systems, fuzzy control, fuzzy data analysis, decision making and fuzzy set models in operations research. All chapters have been updated. Exercises are included.

Principles of Neural Science

Abstract: I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or