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Surveys in combinatorial optimization
131
Book Reviews
tween these two so-called approaches is never made completely clear. In the first case the author says that inventory is viewed as a buffer against uncertainty and in the second as a form of stored capacity. The second chapter, entitled 'Material Coordination' discusses a variety of qualitative issues in a rather cursory manner. Issues of aggregation of units and aggregation of portions of the production process are treated as well as a mention of such fundamental topics as strategic planning, reorder level and base stock systems, and materials requirements planning. The reader unfamiliar with these topics will learn little from these brief descriptions. Chapter 3 launches into the development of a specific model. The model is of a production process in which n products are produced by a single production unit. The very restrictive assumption is included that the demands for products are independent Poisson processes with identical rates. The author shows in general how one would go about determining the stationary distribution of the inventory position. In principal, such methods have been known for at least 30 years. A capacity oriented strategy is now defined as one in which the inventory position is summed over all products. An approximation is suggested that requires making the inventory positions of all products equal. The only structural results are those previously derived by Wijngaard which specify the form of the optimal strategy. The chapter is completed with a set of numerical examples. In Chapter 4 the results of the previous are generalized to the case where the demand can be expressed as the sum of a deterministic and a random component. The formulas derived in the previous chapter are extended to this case. Chapter 5 addresses the more realistic case where the products are not identical. The differences in the products could be due to differences in the production rate, the costs, a n d / o r the demand. However, the assumption that the demand process for each product follows a Poisson process is retained. Products are classified as either slow movers or fast movers, based presumably on the demand rate. Unfortunately, these categories are never rigorously defined, and no methodology is presented for distinguishing these two types of items. The analysis of this chapter in-
volves using Markovian analysis to determine the stationary distribution of the inventory positions of the fast and slow movers. The final chapter claims to present a simple example of the method, but the discussion is strictly qualitative. No actual calculations are presented: I frankly had difficulty divining the theme of this book. I still do not completely understand the author's use of the term capacity. It is evidently not used in the conventional manner to mean a bound on the number of units that can be produced or stored in any period. Capacity is apparently used to mean inventory since the amount of stored capacity in the system is merely the sum of the inventory positions of the products. English is obviously not the author's first language. The writing quality leaves a great deal to be desired, and this undoubtedly contributes to the ambiguity. I believe that better organization and better choice of terminology would have greatly improved this monograph. Steven NA H M I A S Santa Clara University Santa Clara, USA
S. M A R T E L L O , G. LAPORTE, M. M I N O U X and C. R I B E I R O (eds.)
Surveys in Combinatorial Optimization North-Holland, Amsterdam, 1987, x + 384 pages, Dfl. 175.00 Based on the lectures given at the School on Combinatorial Optimization, held at the Federal University of Rio de Janeiro in 1985, the book is a collection of survey papers, which give wide and deep accounts of recent advances in several important fields of Combinatorial Optimization. The papers range from theoretical aspects of fundamental importance in Combinatorial Optimization, like Boolean Programming and Probabilistic Analysis of Algorithms, to several problems, which play a crucial role in the applications. These include classical models, like Linear and Quadratic Assignment Problems, the Knapsack Problem, the Steiner Problem in Graphs. Originated from concrete optimization problems, such models have played a crucial role in the
Book Reviews
132
development of Combinatorial Optimization and, more generally, of Combinatorics. Very appropriately the book emphasizes such a role and carries on the treatment of the models as prototypes of hard-to-solve combinatorial problems. The book contains also some applications oriented papers devoted to important combinatorial problems arising in technical, industrial or economic fields like communications networks, location on networks, vehicle routing, manufacturing and planning in production systems. Very suitably the book, which must be considered of fundamental importance for realizing what Combinatorial Optimization is nowadays, includes a good account of recent work on the use of vector processing and parallel computers for implementing algorithms.
Franco GIANNESSI Department of Mathematics University of P&a Via Buonarotti, 2 56100 Pisa, Italy
Ching-Lai HWANG and Ming-Jeng LIN
Group Decision Making under Multiple Criteria: Methods and Applications Volume 281 in: Lecture Notes in Economics and Mathematical Systems, Springer, Berlin, 1987, xi + 400 pages, DM 70.00 The purpose of this 400 page, double space typed, text is to discuss multiple criteria approaches for group decision making. The book is divided into three parts: Social Choice Theory, Expert Judgment and Group Participation Approaches, and Game Theoretic Approaches. Most of the emphasis in the text is on the second part. The majority of the discussions and approaches considered have a highly algorithmic flavor. The first part of the text discusses voting, social choice, and social welfare functions. The treatment is relatively classical and some of the newer approaches, such as preferential voting do not seem to be discussed. Part two of the book contains sixteen chapters, with essentially each one discussing a different approach for combining expert judgments and group participation. Individually, the chapters are
well written. There is virtually no effort to integrate the approaches used, nor to contrast and compare them. The influence diagram approach, and the structured modeling approach, are not discussed. There is also no discussion of the many group decision support system approaches that are now available. The two overview papers by Geoffrion, and DeSanctis and Gallupe, in the May 1987 issue of Management Science provide excellent supplementation to the presentation in this text. There is also a wealth of literature in behavioral psychology concerning human judgment and decision making. This aspect of the group decision making problem is also not discussed. The last portion of the book, as previously noted, deals with game theoretic approaches. Presented is a nice summary of the classical work in this area. In general, the book can be praised for presenting concisely worded descriptions, generally algorithmic, of several approaches to group decision making. The reference list is especially lengthy. The book is not complete in that a number of recent efforts are not discussed, there is very little attempt to integrate or contrast and compare the several approaches discussed, and the behavioral aspects of the approaches are generally not discussed. Finally, the lack of an index is an impediment to use of the work. Thus, we have a primarily useful, although incomplete, work that serves a convenient purpose in bringing this collection of approaches together.
Andrew P. SAGE George Mason University Fairfax, USA
J.P. VAN GIGCH (ed.)
Decision Making about Decision Making: Metamodels and Metasystems Abacus, Tunbridge Wells, Kent T N 4 0 H U , 1986, xii + 304 pages, £27.00 In the introduction of this work, Stafford Beer states: "We should be looking at problems themselves, not their content. The likelihood is that the content of the problem has been generated at root by limitations of the brain as a machine for reasorting, and by the [imitations of the logic which
Book Reviews
tween these two so-called approaches is never made completely clear. In the first case the author says that inventory is viewed as a buffer against uncertainty and in the second as a form of stored capacity. The second chapter, entitled 'Material Coordination' discusses a variety of qualitative issues in a rather cursory manner. Issues of aggregation of units and aggregation of portions of the production process are treated as well as a mention of such fundamental topics as strategic planning, reorder level and base stock systems, and materials requirements planning. The reader unfamiliar with these topics will learn little from these brief descriptions. Chapter 3 launches into the development of a specific model. The model is of a production process in which n products are produced by a single production unit. The very restrictive assumption is included that the demands for products are independent Poisson processes with identical rates. The author shows in general how one would go about determining the stationary distribution of the inventory position. In principal, such methods have been known for at least 30 years. A capacity oriented strategy is now defined as one in which the inventory position is summed over all products. An approximation is suggested that requires making the inventory positions of all products equal. The only structural results are those previously derived by Wijngaard which specify the form of the optimal strategy. The chapter is completed with a set of numerical examples. In Chapter 4 the results of the previous are generalized to the case where the demand can be expressed as the sum of a deterministic and a random component. The formulas derived in the previous chapter are extended to this case. Chapter 5 addresses the more realistic case where the products are not identical. The differences in the products could be due to differences in the production rate, the costs, a n d / o r the demand. However, the assumption that the demand process for each product follows a Poisson process is retained. Products are classified as either slow movers or fast movers, based presumably on the demand rate. Unfortunately, these categories are never rigorously defined, and no methodology is presented for distinguishing these two types of items. The analysis of this chapter in-
volves using Markovian analysis to determine the stationary distribution of the inventory positions of the fast and slow movers. The final chapter claims to present a simple example of the method, but the discussion is strictly qualitative. No actual calculations are presented: I frankly had difficulty divining the theme of this book. I still do not completely understand the author's use of the term capacity. It is evidently not used in the conventional manner to mean a bound on the number of units that can be produced or stored in any period. Capacity is apparently used to mean inventory since the amount of stored capacity in the system is merely the sum of the inventory positions of the products. English is obviously not the author's first language. The writing quality leaves a great deal to be desired, and this undoubtedly contributes to the ambiguity. I believe that better organization and better choice of terminology would have greatly improved this monograph. Steven NA H M I A S Santa Clara University Santa Clara, USA
S. M A R T E L L O , G. LAPORTE, M. M I N O U X and C. R I B E I R O (eds.)
Surveys in Combinatorial Optimization North-Holland, Amsterdam, 1987, x + 384 pages, Dfl. 175.00 Based on the lectures given at the School on Combinatorial Optimization, held at the Federal University of Rio de Janeiro in 1985, the book is a collection of survey papers, which give wide and deep accounts of recent advances in several important fields of Combinatorial Optimization. The papers range from theoretical aspects of fundamental importance in Combinatorial Optimization, like Boolean Programming and Probabilistic Analysis of Algorithms, to several problems, which play a crucial role in the applications. These include classical models, like Linear and Quadratic Assignment Problems, the Knapsack Problem, the Steiner Problem in Graphs. Originated from concrete optimization problems, such models have played a crucial role in the
Book Reviews
132
development of Combinatorial Optimization and, more generally, of Combinatorics. Very appropriately the book emphasizes such a role and carries on the treatment of the models as prototypes of hard-to-solve combinatorial problems. The book contains also some applications oriented papers devoted to important combinatorial problems arising in technical, industrial or economic fields like communications networks, location on networks, vehicle routing, manufacturing and planning in production systems. Very suitably the book, which must be considered of fundamental importance for realizing what Combinatorial Optimization is nowadays, includes a good account of recent work on the use of vector processing and parallel computers for implementing algorithms.
Franco GIANNESSI Department of Mathematics University of P&a Via Buonarotti, 2 56100 Pisa, Italy
Ching-Lai HWANG and Ming-Jeng LIN
Group Decision Making under Multiple Criteria: Methods and Applications Volume 281 in: Lecture Notes in Economics and Mathematical Systems, Springer, Berlin, 1987, xi + 400 pages, DM 70.00 The purpose of this 400 page, double space typed, text is to discuss multiple criteria approaches for group decision making. The book is divided into three parts: Social Choice Theory, Expert Judgment and Group Participation Approaches, and Game Theoretic Approaches. Most of the emphasis in the text is on the second part. The majority of the discussions and approaches considered have a highly algorithmic flavor. The first part of the text discusses voting, social choice, and social welfare functions. The treatment is relatively classical and some of the newer approaches, such as preferential voting do not seem to be discussed. Part two of the book contains sixteen chapters, with essentially each one discussing a different approach for combining expert judgments and group participation. Individually, the chapters are
well written. There is virtually no effort to integrate the approaches used, nor to contrast and compare them. The influence diagram approach, and the structured modeling approach, are not discussed. There is also no discussion of the many group decision support system approaches that are now available. The two overview papers by Geoffrion, and DeSanctis and Gallupe, in the May 1987 issue of Management Science provide excellent supplementation to the presentation in this text. There is also a wealth of literature in behavioral psychology concerning human judgment and decision making. This aspect of the group decision making problem is also not discussed. The last portion of the book, as previously noted, deals with game theoretic approaches. Presented is a nice summary of the classical work in this area. In general, the book can be praised for presenting concisely worded descriptions, generally algorithmic, of several approaches to group decision making. The reference list is especially lengthy. The book is not complete in that a number of recent efforts are not discussed, there is very little attempt to integrate or contrast and compare the several approaches discussed, and the behavioral aspects of the approaches are generally not discussed. Finally, the lack of an index is an impediment to use of the work. Thus, we have a primarily useful, although incomplete, work that serves a convenient purpose in bringing this collection of approaches together.
Andrew P. SAGE George Mason University Fairfax, USA
J.P. VAN GIGCH (ed.)
Decision Making about Decision Making: Metamodels and Metasystems Abacus, Tunbridge Wells, Kent T N 4 0 H U , 1986, xii + 304 pages, £27.00 In the introduction of this work, Stafford Beer states: "We should be looking at problems themselves, not their content. The likelihood is that the content of the problem has been generated at root by limitations of the brain as a machine for reasorting, and by the [imitations of the logic which