A heuristic method for aggregate planning: Production decision framework

This paper presents an understandable and straight-forward method for making work force level and inventory planning decisions, i.e., dynamic aggregate planning decisions.The development phase utilizes a ratio, named RPCC, which represents the relative value of the cost of changing the production level to the cost of carrying inventory. This ratio is used to determine the length of an effective planning horizon. Two indicators are calculated to reflect the demand to current production rate over different time periods. Based on the joint values of these indicators, the planning problem is subdivided into one of nine mutually exclusive and exhaustive states. A set of action statements, representing logical responses to each of the sub-problems, is formulated.After completion of the development phase, the performance of the Production Decision Framework model is tested in several real case environments. Suggestions are made for further improvement.     

A decision problem of long-term economic planning

The model described in the present paper has been worked out to approximate a concrete problem of national economic planning. The problem presented itself in the daily practice of the National Planning Board of the Hungarian People's Republic in the course of a planning project carried out with the aim of laying the foundation of the national economy's long-term development.     

The new view of the property tax A reformulation

The ‘new view’ of the property tax is reformulated within the context of a model with interjurisdictional competition, endogenous local public services, individuals who are segregated into homogeneous communities according to tastes for local public services, a simple form of land use zoning, and a political or constitutional constraint on the use of head taxes by local governments. Expressions for the ‘profits tax’ and ‘excise tax’ effects of the property tax are derived. The effects of a ‘consumption distortion’ away from government services due to local reluctance to tax mobile capital are also examined.     

PDF versus LP: An empirical aggregate planning comparison

Production Decision Framework (PDF) is a recently introduced heuristic method for solving the aggregate planning problem. The algorithm was developed and tested over a wide range of deterministic demand patterns and cost parameters. The decision by Wayn-Tex Inc., to adopt the methodology provided a real world opportunity to evaluate the performance of PDF under uncertainty over a one year's operating period.This paper concentrated on a study of (1) the effectiveness of the model in selecting a suitable rolling planning horizon, and (2) the performance of PDF as compared to a linear program solution using the same length horizon. The monthly sales forecast used in the study, developed by the sales department, took into consideration trend, seasonality, and known market conditions. The results were gratifying. Management has indicated their desire to continue using PDF as a guide in the production planning process through the use of the computerized program available.     

配网规划准确率问题的分析

新时期,我国城市化建设面临了新的局面和机遇,社会各个方面的基础建设都面临着全新的调整和发展。配电网是电力系统中的主要构成,配电网规划是后期施工建设的总指导,在规划配电网期间要做多个方面的分析处理,结合有效的数据才能分析配电网规划的有效方案。针对这一点,文章重点分析了配电网规划准确率的相关问题,旨在保证配电网工程项目的有效进行。     

Alternative approaches for the reformulation of economics

Journal of Economic Interaction and Coordination -     

电网规划问题分析及规划模型研究

电网规划是电力系统规划的重要组成部分,其任务是根据规划期间的负荷增长给电源规划方案确定相应的最佳电网结构,以满足经济可靠送电的要求。文章介绍了电网规划问题的基本理论和影响电网规划的因素,阐述了电网结构在电网规划中的重要性,最后,对电网规划数学模型进行了研究,为电网规划优化问题提供了理论基础。     

电网规划问题分析及规划模型研究

电网规划是电力系统规划的重要组成部分,其任务是根据规划期间的负荷增长给电源规划方案确定相应的最佳电网结构,以满足经济可靠送电的要求.文章介绍了电网规划问题的基本理论和影响电网规划的因素,阐述了电网结构在电网规划中的重要性,最后,对电网规划数学模型进行了研究,为电网规划优化问题提供了理论基础.     

A reformulation of the maxmin expected utility model with application to agency theory

Invoking the parameterized distribution formulation of agency theory, the paper develops axiomatic foundations of the principal’s and agent’s choice behaviors that are representable by the maximization of the minimum expected utility over action-dependent sets of priors. In the context of this model, the paper also discusses some implications of ambiguity aversion for the design of optimal incentive schemes.     

A multimodal,multicommodity, and multiperiod planning problem for coal distribution to poor families

Tackling poverty has been one of the greatest global challenges and a prerequisite to sustainable development of countries. Countries implement nationally appropriate social protection systems and measures to address poverty. This paper addresses an aid system adopted by the government in Turkey where significant amounts of coal is distributed to poor families each year. The objective of the coal aid system is to complete the delivery of coal to poor families by the start of winter. However, an analysis of the data from previous years indicates that the distribution to many families cannot be completed on time. This results from the fact that planning is done manually and by trial-and-error as there is no system that can be used for distribution planning. This paper describes the planning problem encountered and develops a mathematical model to solve it. The proposed model is a multimodal, multicommodity, and multiperiod linear programming (LP) model. The model can be used to develop and update a distribution plan as well as to answer several what-if questions with regard to capacities, time constraints, and so forth. The model is solved using CPLEX for several problem instances obtained under different scenarios using data for the year 2012. The results show that at least 9% cost savings and about 40% decrease in distribution completion time can be achieved when the model is used. We analyze scenario results qualitatively and quantitatively and provide several insights to the decision makers. As a part of quantitative analysis, we develop regression models to predict optimal costs based on several factors. Our main contribution is to provide an efficient and effective tool to handle a large-scale real-world problem. The model has also helped to prove that the organization responsible for distribution planning may move from the current planning practice to an all-encompassing top-down approach.     

A management planning model for the delivery of family planning services

A management planning model for the delivery of family planning services is presented. Markovian probabilistic properties have been adapted for projecting patient flow for a set of various alternative strategies for scheduling patient visits in a health care system. By quantitatively formulating the scheduling problem in terms of pertinent inputs, management objectives and imposed restrictions, optimization of patient flow in the system for efficient utilization of health care resources is achieved through standard linear programming techniques.     

A structural model of US aggregate job flows

This paper contributes to the analysis of jobs flows dynamics through the explicit modelling of job creations and job destructions. We propose a simple matching model extended for endogenous separation and tractable heterogeneity. The parameters of the model are estimated using a simulation‐based estimation method. We then test the ability of trade externalities, generated by the matching process, to (i) propagate reallocation and aggregate disturbances in the whole labor market and (ii) generate the observed distribution of aggregate job flows. The results clearly indicate that the model is able to match the dynamics of US aggregate job flows. Copyright © 2002 John Wiley & Sons, Ltd.     

A time varying parameter approach to the Chinese aggregate consumption function

China experienced a number of economic, political and social upheavals in the pre-reform period, together with a gradual transformation from a centrally-planned to a market oriented economy in the post-reform period. Given this background of extensive change, a time varying parameter (TVP) consumption model for non-durables is developed in order to determine the resulting changes in consumer behaviour caused by both observable and unobservable factors. The parameters of interest are the short and long run marginal propensities to consume (MPC) and the long run average propensity to consume (APC). The model is based on Friedman's permanent income hypothesis (PIH) and estimated using the Kalman filter algorithm. The empirical results suggest that the TVP model is a good representation of the changes in Chinese consumer behaviour over time. In terms of forecasting, the TVP model generally outperforms a number of alternative models.     

A novel decomposition of aggregate total factor productivity change

Journal of Productivity Analysis - An industry is an ensemble of individual firms (decision making units) which may or may not interact with each other. Similarly, an economy is an ensemble of...     

Comparisons of aggregate variable forecasts using aggregate and disaggregate models

When forecasting aggregate variables, a choice must often be made to either add up individual forecasts made at a disaggregate level or to simply forecast at the aggregate level. The presence of heterogeneity introduces aggregation bias and makes the disaggregates approach more preferable, while the presence of data and specification errors introduces relatively large variances in the disaggregate forecasts, making the aggregate approach more preferable. It is suggested that the mean square error is useful in evaluating the combined effects of heterogeneity and specification and data errors, and in facilitating comparisons between aggregate and disaggregate approaches to aggregate variable forecasting.     

A statistical treatment of the problem of division

The problem of division is one of the most important problems in the emergence of probability. It has been long considered solved from a probabilistic viewpoint. However, we do not find the solution satisfactory. In this study, the problem is recasted as a statistical problem. The outcomes of matches of the game are considered as an infinitely exchangeable random sequence and predictors/estimators are constructed in light of de Finetti representation theorem. Bounds of the estimators are derived over wide classes of priors (mixing distributions). We find that, although conservative, the classical solutions are justifiable by our analysis while the plug-in estimates are too optimistic for the winning player.Acknowledgement. The authors would like to thank the referees for the insightful and informative suggestions and, particularly, for referring us to important references.Supported by NSC-88-2118-M-259-009.Supported in part by NSC 89-2118-M-259-012.Received August 2002