Surrogate Search As a Way to Combat Harmful Effects of Ill-behaved Evaluation Functions

Recently, several researchers have found that cost-based satisficing search with A* often runs into problems. Although some "work arounds" have been proposed to ameliorate the problem, there has been little concerted effort to pinpoint its origin. In this paper, we argue that the origins of this problem can be traced back to the fact that most planners that try to optimize cost also use cost-based evaluation functions (i.e., f(n) is a cost estimate). We show that cost-based evaluation functions become ill-behaved whenever there is a wide variance in action costs; something that is all too common in planning domains. The general solution to this malady is what we call a surrogatesearch, where a surrogate evaluation function that doesn't directly track the cost objective, and is resistant to cost-variance, is used. We will discuss some compelling choices for surrogate evaluation functions that are based on size rather that cost. Of particular practical interest is a cost-sensitive version of size-based evaluation function -- where the heuristic estimates the size of cheap paths, as it provides attractive quality vs. speed tradeoffsComment: arXiv admin note: substantial text overlap with arXiv:1103.368

Harmful Freedom of Choice: Lessons from the Cellphone Market

This article focuses on the relationship between provider and customer, specifically on the complexity of available contracts in the cellphone market and the ways this complexity might be harmful to consumers. This article aims to elucidate the issues, fleshing them out both as a general phenomenon and as a specific implementation in the cellphone context. The aim is not to provide ultimate solutions, but to show the directions these solutions might take and the difficulties involved

Learning Classical Planning Strategies with Policy Gradient

A common paradigm in classical planning is heuristic forward search. Forward search planners often rely on simple best-first search which remains fixed throughout the search process. In this paper, we introduce a novel search framework capable of alternating between several forward search approaches while solving a particular planning problem. Selection of the approach is performed using a trainable stochastic policy, mapping the state of the search to a probability distribution over the approaches. This enables using policy gradient to learn search strategies tailored to a specific distributions of planning problems and a selected performance metric, e.g. the IPC score. We instantiate the framework by constructing a policy space consisting of five search approaches and a two-dimensional representation of the planner's state. Then, we train the system on randomly generated problems from five IPC domains using three different performance metrics. Our experimental results show that the learner is able to discover domain-specific search strategies, improving the planner's performance relative to the baselines of plain best-first search and a uniform policy.Comment: Accepted for ICAPS 201

Organizationally Sensible vs. Legal-Centric Approaches to Employment Decisions With Legal Implications

This article is intended to: 1) alert human resource (HR) professionals to the risk that they, and the managers they serve, are unnecessarily contributing to the impact of legal considerations on the management of employees as a result of “legal-centric decision making”; and 2) provide information and guidance that will assist HR professionals in promoting better informed, more organizationally sensible responses to employment issues that have potential legal implications. The “legal-centric decision making” construct is introduced and illustrated, a model of the primary factors contributing to legal-centric decision making is presented, and keys to avoiding legal-centric decision making are identified and discussed

Nominalist Heuristics and Economic Theory

This paper introduces a new theoretic entity, a nominalist heuristic, defined as a focus on prominent numbers, indices or ratios. Abstractions used in the evaluation stage of decision making typically involve nominalist heuristics that are incompatible with expected utility theory which excludes the evaluation stage, and are also incompatible with prospect theory which assumes that, while the evaluation procedure can involve systematic mistakes, the overall decision situation is nevertheless sufficiently simple: 1) for economists and psychologists to identify what is a mistake, and 2) to be compatible with maximisation. But in the typical complex situation giving rise to nominalist heuristics neither 1) nor 2) hold, and therefore what is required is a fundamentally different class of models that allow for the progressive anticipated changes in knowledge ahead faced under risk and uncertainty, namely models under the umbrella of SKAT, the Stages of Knowledge Ahead Theory. A sequel paper. Pope et al 2009b, shows field and laboratory evidence of heuristics in the form of prominent numbers entering exchange rate determination.nominalism, money illusion, heuristic, unpredictability, experiment, SKAT the Stages of Knowledge Ahead Theory, prominent numbers, prominent indices, prominent ratios, equality, historical benchmarks, complexity, decision costs, evaluation

The decision-making entrepreneur; Literature review

This study provides a literature overview of the entrepreneurial decision-making process. The literature review is used as background information for a qualitative study, which investigates, by means of case studies, the decision-making process of small business enterpreneurs in The Netherlands (Gibcus and Van Hoesel, 2003). The literature overview is the starting point of a confrontation between the literature on decision-making and the empirical findings of the latter qualitive study. Firstly, this literature review gives an introduction to general decision theory. It discusses the classical rationality, the bounded rationality and the neoclassical rationality. The place of the entrepreneur in the general decision theory is also discussed. Next, an analytic framework of the strategic decision-making in SMEs is presented. The analytic framework consists of three elements: the entrepreneur, the environment and the strategic decision process. Each of these elements is critical. Finally, some earlier empirical findings on entrepreneurial strategic decision-making are discussed.

Solution and quality robust project scheduling: a methodological framework.

The vast majority of the research efforts in project scheduling over the past several years has concentrated on the development of exact and suboptimal procedures for the generation of a baseline schedule assuming complete information and a deterministic environment. During execution, however, projects may be the subject of considerable uncertainty, which may lead to numerous schedule disruptions. Predictive-reactive scheduling refers to the process where a baseline schedule is developed prior to the start of the project and updated if necessary during project execution. It is the objective of this paper to review possible procedures for the generation of proactive (robust) schedules, which are as well as possible protected against schedule disruptions, and for the deployment of reactive scheduling procedures that may be used to revise or re-optimize the baseline schedule when unexpected events occur. We also offer a methodological framework that should allow project management to identify the proper scheduling methodology for different project scheduling environments. Finally, we survey the basics of Critical Chain scheduling and indicate in which environments it is useful.Framework; Information; Management; Processes; Project management; Project scheduling; Project scheduling under uncertainty; Stability; Robust scheduling; Quality; Scheduling; Stability; Uncertainty;