The Experts below are selected from a list of 2010 Experts worldwide ranked by ideXlab platform
Evan L. Porteus - One of the best experts on this subject based on the ideXlab platform.
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©2006 INFORMS A Fractiles Perspective to the Joint Price/Quantity Newsvendor Model
2016Co-Authors: Gal Raz, Evan L. PorteusAbstract:Pricing and quantity decisions are critical to many firms across different industries. We study the jointprice/quantity newsvendor model where only a single quantity and price decision is made, such as a fash-ion or holiday product that cannot be replenished and where the price is advertised nationally and cannot be changed. Demand is uncertain and sensitive to price. We develop a method for easily finding the optimal price and quantity that applies to more general cases than the usual one in which uncertainty is either additive, multiplicative, or a combination of the two. We represent a quantity by its fractile of the probability distribution of demand for a given price. We use a standard approach to approximating a given distribution with a finite number of representative Fractiles and assume that these fractile functions are piecewise linear functions of the price. We identify effects that are not usually seen in a joint price/quantity newsvendor model. For example, although the optimal quantity is a decreasing function of the unit cost, the optimal price can be nonmonotone in the unit cost and we shed insight into why. We illustrate that using a simplified structure of demand uncertainty can result in substantially lower profits. Key words: pricing; simultaneous production planning; newsvendor model; supply chain management History: Accepted by Candace A. Yano, operations and supply chain management; received November 13, 2003. This paper was with the authors 1 year and 3 months for 3 revisions. 1
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a Fractiles perspective to the joint price quantity newsvendor model
Management Science, 2006Co-Authors: Gal Raz, Evan L. PorteusAbstract:Pricing and quantity decisions are critical to many firms across different industries. We study the joint price/quantity newsvendor model where only a single quantity and price decision is made, such as a fashion or holiday product that cannot be replenished and where the price is advertised nationally and cannot be changed. Demand is uncertain and sensitive to price. We develop a method for easily finding the optimal price and quantity that applies to more general cases than the usual one in which uncertainty is either additive, multiplicative, or a combination of the two. We represent a quantity by its fractile of the probability distribution of demand for a given price. We use a standard approach to approximating a given distribution with a finite number of representative Fractiles and assume that these fractile functions are piecewise linear functions of the price. We identify effects that are not usually seen in a joint price/quantity newsvendor model. For example, although the optimal quantity is a decreasing function of the unit cost, the optimal price can be nonmonotone in the unit cost and we shed insight into why. We illustrate that using a simplified structure of demand uncertainty can result in substantially lower profits.
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A Fractiles Perspective to the Joint Price/Quantity Newsvendor Model
Management Science, 2006Co-Authors: Gal Raz, Evan L. PorteusAbstract:Pricing and quantity decisions are critical to many firms across different industries. We study the joint price/quantity newsvendor model where only a single quantity and price decision is made, such as a fashion or holiday product that cannot be replenished and where the price is advertised nationally and cannot be changed. Demand is uncertain and sensitive to price. We develop a method for easily finding the optimal price and quantity that applies to more general cases than the usual one in which uncertainty is either additive, multiplicative, or a combination of the two. We represent a quantity by its fractile of the probability distribution of demand for a given price. We use a standard approach to approximating a given distribution with a finite number of representative Fractiles and assume that these fractile functions are piecewise linear functions of the price. We identify effects that are not usually seen in a joint price/quantity newsvendor model. For example, although the optimal quantity is a decreasing function of the unit cost, the optimal price can be nonmonotone in the unit cost and we shed insight into why. We illustrate that using a simplified structure of demand uncertainty can result in substantially lower profits.
Hitoshi Yano - One of the best experts on this subject based on the ideXlab platform.
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Interactive multiobjective Fuzzy random linear programming through fractile criteria
Advances in Fuzzy Systems, 2012Co-Authors: Hitoshi Yano, Masatoshi SakawaAbstract:We propose an interactive fuzzy decision making method for multiobjective fuzzy random linear programming problems through fractile criteria optimization. In the proposed method, it is assumed that the decision maker has fuzzy goals for not only objective functions but also permissible probability levels in a fractile optimization model, and such fuzzy goals are quantified by eliciting the corresponding membership functions. Using the fuzzy decision, such two kinds of membership functions are integrated. In the integrated membership space, the satisfactory solution is obtained from among an extended Pareto optimal solution set through the interaction with the decision maker. An illustrative numerical example is provided to demonstrate the feasibility and efficiency of the proposed method.
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An Interactive Fuzzy Satisficing Method for Multiobjective Stochastic Linear Programming Problems Considering Both Probability Maximization and Fractile Optimization
Intelligent Decision Technologies, 2012Co-Authors: Hitoshi YanoAbstract:In this paper, we propose an interactive fuzzy satisficing method for multiobjective stochastic linear programming problems to obtain a satisficing solution, in which the criteria of probability maximization and fractile optimization are considered simultaneously. In the proposed method, it is assumed that the decision maker has fuzzy goals for not only permissible objective levels of a probability maximization model but also permissible probability levels of a fractile criterion optimization model. After eliciting the corresponding membership functions for the fuzzy goals, two kinds of membership functions for permissible objective levels and permissible probability levels are integrated through the fuzzy decision. An interactive algorithm is proposed to obtain a satisficing solution from among a D f -Pareto optimal solution set.
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FUZZ-IEEE - Fuzzy approaches for multiobjective stochastic linear programming problems considering both probability maximization and fractile optimization
2011 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE 2011), 2011Co-Authors: Hitoshi YanoAbstract:In this paper, we propose two kinds of fuzzy approaches to obtain a satisfactory solution for multiobjective stochastic linear programming problems, in which the criteria of probability maximization and fractile optimization are considered simultaneously. In the first approach, a probability maximization model is applied to multiobjective stochastic linear programming problems, where the decision maker is required to specify not permissible objective levels but the corresponding membership functions which represent fuzzy goals for permissible objective levels. By adopting the fuzzy decision to integrate both the membership functions for permissible objective levels and the ones for the probability functions, a probability maximization model is transformed to the maxmin problem without permissible objective levels as parameters. Similarly, in the second approach, a fractile optimization model is applied to multiobjective stochastic linear programming problems, where the decision maker is required to specify not permissible probability levels but the corresponding membership functions which represent fuzzy goals for permissible probability levels. By adopting the fuzzy decision to integrate both the membership functions for permissible probability levels and the ones for the objective functions, a fractile optimization model is transformed to the maxmin problem without permissible probability levels as parameters. It is shown that such two fuzzy approaches are same.
Gal Raz - One of the best experts on this subject based on the ideXlab platform.
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©2006 INFORMS A Fractiles Perspective to the Joint Price/Quantity Newsvendor Model
2016Co-Authors: Gal Raz, Evan L. PorteusAbstract:Pricing and quantity decisions are critical to many firms across different industries. We study the jointprice/quantity newsvendor model where only a single quantity and price decision is made, such as a fash-ion or holiday product that cannot be replenished and where the price is advertised nationally and cannot be changed. Demand is uncertain and sensitive to price. We develop a method for easily finding the optimal price and quantity that applies to more general cases than the usual one in which uncertainty is either additive, multiplicative, or a combination of the two. We represent a quantity by its fractile of the probability distribution of demand for a given price. We use a standard approach to approximating a given distribution with a finite number of representative Fractiles and assume that these fractile functions are piecewise linear functions of the price. We identify effects that are not usually seen in a joint price/quantity newsvendor model. For example, although the optimal quantity is a decreasing function of the unit cost, the optimal price can be nonmonotone in the unit cost and we shed insight into why. We illustrate that using a simplified structure of demand uncertainty can result in substantially lower profits. Key words: pricing; simultaneous production planning; newsvendor model; supply chain management History: Accepted by Candace A. Yano, operations and supply chain management; received November 13, 2003. This paper was with the authors 1 year and 3 months for 3 revisions. 1
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a Fractiles perspective to the joint price quantity newsvendor model
Management Science, 2006Co-Authors: Gal Raz, Evan L. PorteusAbstract:Pricing and quantity decisions are critical to many firms across different industries. We study the joint price/quantity newsvendor model where only a single quantity and price decision is made, such as a fashion or holiday product that cannot be replenished and where the price is advertised nationally and cannot be changed. Demand is uncertain and sensitive to price. We develop a method for easily finding the optimal price and quantity that applies to more general cases than the usual one in which uncertainty is either additive, multiplicative, or a combination of the two. We represent a quantity by its fractile of the probability distribution of demand for a given price. We use a standard approach to approximating a given distribution with a finite number of representative Fractiles and assume that these fractile functions are piecewise linear functions of the price. We identify effects that are not usually seen in a joint price/quantity newsvendor model. For example, although the optimal quantity is a decreasing function of the unit cost, the optimal price can be nonmonotone in the unit cost and we shed insight into why. We illustrate that using a simplified structure of demand uncertainty can result in substantially lower profits.
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A Fractiles Perspective to the Joint Price/Quantity Newsvendor Model
Management Science, 2006Co-Authors: Gal Raz, Evan L. PorteusAbstract:Pricing and quantity decisions are critical to many firms across different industries. We study the joint price/quantity newsvendor model where only a single quantity and price decision is made, such as a fashion or holiday product that cannot be replenished and where the price is advertised nationally and cannot be changed. Demand is uncertain and sensitive to price. We develop a method for easily finding the optimal price and quantity that applies to more general cases than the usual one in which uncertainty is either additive, multiplicative, or a combination of the two. We represent a quantity by its fractile of the probability distribution of demand for a given price. We use a standard approach to approximating a given distribution with a finite number of representative Fractiles and assume that these fractile functions are piecewise linear functions of the price. We identify effects that are not usually seen in a joint price/quantity newsvendor model. For example, although the optimal quantity is a decreasing function of the unit cost, the optimal price can be nonmonotone in the unit cost and we shed insight into why. We illustrate that using a simplified structure of demand uncertainty can result in substantially lower profits.
Douglas H. Werner - One of the best experts on this subject based on the ideXlab platform.
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Comparison of the peano-gosper fractile array and the regular hexagonal array
Microwave and Optical Technology Letters, 2004Co-Authors: J.n. Bogard, Douglas H. Werner, P.l. WernerAbstract:A new class of modular broadband low-sidelobe arrays, based on the theory of fractile (fractal tile) geometry, has been recently introduced. In this paper, the radiation properties of the Peano–Gosper fractile array are compared to those of the conventional square and hexagonal arrays. It is demonstrated that the Peano–Gosper array has the same desirable grating-lobe conditions as the hexagonal array, while achieving a much lower overall sidelobe level. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 524–526, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20523
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Fractile arrays: a new class of broadband tiled arrays with fractal boundaries
IEEE Antennas and Propagation Society Symposium 2004., 2004Co-Authors: Douglas H. Werner, W. Kuhirun, P.l. WernerAbstract:A class of antenna arrays are introduced, which we call fractile arrays. A fractile array is defined as any array with a fractal boundary contour that tiles the plane without gaps or overlaps. It is shown that the unique geometrical features of Fractiles may be exploited in order to make available a family of deterministic arrays that offer several highly desirable performance advantages over their conventional periodic planar array counterparts. Most notably, fractile arrays have no grating lobes even when the minimum spacing between elements is increased to at least one-wavelength. This has led to the development of a new design methodology for modular broadband arrays that is based on fractal tilings. Several examples of fractile arrays are considered including Peano-Gosper, terdragon, six-terdragon, and fudgeflake arrays. Efficient iterative procedures for calculating the radiation patterns of these fractile arrays to arbitrary stage of growth P are also introduced.
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Fractile arrays: a new class of tiled arrays with fractal boundaries
IEEE Transactions on Antennas and Propagation, 2004Co-Authors: Douglas H. Werner, W. Kuhirun, P.l. WernerAbstract:In this paper, a new class of antenna arrays are introduced, which we call fractile arrays. A fractile array is defined as any array with a fractal boundary contour that tiles the plane without gaps or overlaps. It will be shown that the unique geometrical features of Fractiles may be exploited in order to make available a family of deterministic arrays that offer several highly desirable performance advantages over their conventional periodic planar array counterparts. Most notably, fractile arrays have no grating lobes even when the minimum spacing between elements is increased to at least one-wavelength. This has led to the development of a new design methodology for modular broadband low-sidelobe arrays that is based on fractal tilings. Several examples of fractile arrays will be considered including Peano-Gosper, terdragon, 6-terdragon, and fudgeflake arrays. Efficient iterative procedures for calculating the radiation patterns of these fractile arrays to arbitrary stage of growth P are also introduced in this paper.
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Fractile Arrays: A New Class of Tiled Arrays With
2004Co-Authors: Douglas H. Werner, W. Kuhirun, P.l. WernerAbstract:In this paper, a new class of antenna arrays are in- troduced, which we call fractile arrays. A fractile array is defined as any array with a fractal boundary contour that tiles the plane without gaps or overlaps. It will be shown that the unique geo- metrical features of Fractiles may be exploited in order to make available a family of deterministic arrays that offer several highly desirable performance advantages over their conventional peri- odic planar array counterparts. Most notably, fractile arrays have no grating lobes even when the minimum spacing between ele- ments is increased to at least one-wavelength. This has led to the development of a new design methodology for modular broadband low-sidelobe arrays that is based on fractal tilings. Several exam- ples of fractile arrays will be considered including Peano-Gosper, terdragon, 6-terdragon, and fudgeflake arrays. Efficient iterative procedures for calculating the radiation patterns of these fractile arrays to arbitrary stage of growth are also introduced in this paper.
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Genetically optimized fractile microstrip patch antennas
IEEE Antennas and Propagation Society Symposium 2004., 2004Co-Authors: T.g. Spence, Douglas H. WernerAbstract:We introduce a new family of microstrip patch antennas that are based upon fractal tile (i.e., fractile) geometries. We call such antennas fractile microstrip antennas. By utilizing the properties of fractal tiles, it is possible to create single-feed modular designs for microstrip patch antennas with broadside gains that are in excess of 12 dB when they are operated to excite high-order localized modes. Two examples of fractile microstrip patch antenna configurations are presented, namely the fudgeflake and Gosper island microstrip antennas. In the design of these antennas, a genetic algorithm was employed to optimize their performance.
Hon-shiang Lau - One of the best experts on this subject based on the ideXlab platform.
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A comparison of procedures for estimating the parent probability distribution from a given set of Fractiles
European Journal of Operational Research, 2000Co-Authors: Hon-shiang Lau, Amy Hing-ling Lau, John F. KottasAbstract:Abstract On one hand, eliciting subjective probabilities (Fractiles) is a well-established procedure. On the other hand, knowledge of a subjective variable's central moments or distribution function is often assumed. However, the problem of converting elicited Fractiles into the required moments or distribution function has been largely ignored. We show that this conversion problem is far from trivial, and that the most commonly used conversion procedures often produce huge errors. Alternative procedures are proposed; the “Tocher's curve” and “linear function of Fractiles” methods are shown to be much more accurate than the commonly used procedures.
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Improved Moment-Estimation Formulas Using More Than Three Subjective Fractiles
Management Science, 1998Co-Authors: Hon-shiang Lau, Amy Hing-ling LauAbstract:PERT-type subjective estimations are used in many stochastic decision models to estimate the random variables mean and standard deviation (s.d.). The approach is based on the beta-distribution assumption; also, most PERT-type formulas use only three estimated Fractiles. We point out that: (i) it is desirable to consider a substantially richer set of distributions than the beta in developing PERT-type formulas; (ii) it may be beneficial to use more than three fractile-estimates in PERT-type formulas. We then develop formulas for estimating the mean and s.d. that are based on a substantially richer set of distributions than the beta and that use more than three estimated Fractiles. These formulas perform better than the best currently-vailable formulas when the subjective distribution is not restricted to be beta.
