Social Preference Under Twofold Uncertainty

We investigate the conflict between the ex ante and ex post criteria of social welfare in a new framework of individual and social decisions, which distinguishes between two sources of uncertainty, here interpreted as an objective and a subjective source respectively. This framework makes it possible to endow the individuals and society not only with ex ante and ex post preferences, as is usually done, but also with interim preferences of two kinds, and correspondingly, to introduce interim forms of the Pareto principle. After characterizing the ex ante and ex post criteria, we present a first solution to their conflict that extends the former as much possible in the direction of the latter. Then, we present a second solution, which goes in the opposite direction, and is also maximally assertive. Both solutions translate the assumed Pareto conditions into weighted additive utility representations, and both attribute to the individuals common probability values on the objective source of uncertainty, and different probability values on the subjective source. We discuss these solutions in terms of two conceptual arguments, i.e., the by now classic spurious unanimity argument and a novel informational argument labelled complementary ignorance. The paper complies with the standard economic methodology of basing probability and utility representations on preference axioms, but for the sake of completeness, also considers a construal of objective uncertainty based on the assumption of an exogeneously given probability measure. JEL classification: D70; D81

Enhanced sharing analysis techniques: a comprehensive evaluation

Sharing, an abstract domain developed by D. Jacobs and A. Langen for the analysis of logic programs, derives useful aliasing information. It is well-known that a commonly used core of techniques, such as the integration of Sharing with freeness and linearity information, can significantly improve the precision of the analysis. However, a number of other proposals for refined domain combinations have been circulating for years. One feature that is common to these proposals is that they do not seem to have undergone a thorough experimental evaluation even with respect to the expected precision gains. In this paper we experimentally evaluate: helping Sharing with the definitely ground variables found using Pos, the domain of positive Boolean formulas; the incorporation of explicit structural information; a full implementation of the reduced product of Sharing and Pos; the issue of reordering the bindings in the computation of the abstract mgu; an original proposal for the addition of a new mode recording the set of variables that are deemed to be ground or free; a refined way of using linearity to improve the analysis; the recovery of hidden information in the combination of Sharing with freeness information. Finally, we discuss the issue of whether tracking compoundness allows the computation of more sharing information

An Architectural Approach to Ensuring Consistency in Hierarchical Execution

Hierarchical task decomposition is a method used in many agent systems to organize agent knowledge. This work shows how the combination of a hierarchy and persistent assertions of knowledge can lead to difficulty in maintaining logical consistency in asserted knowledge. We explore the problematic consequences of persistent assumptions in the reasoning process and introduce novel potential solutions. Having implemented one of the possible solutions, Dynamic Hierarchical Justification, its effectiveness is demonstrated with an empirical analysis

On-line planning and scheduling: an application to controlling modular printers

We present a case study of artificial intelligence techniques applied to the control of production printing equipment. Like many other real-world applications, this complex domain requires high-speed autonomous decision-making and robust continual operation. To our knowledge, this work represents the first successful industrial application of embedded domain-independent temporal planning. Our system handles execution failures and multi-objective preferences. At its heart is an on-line algorithm that combines techniques from state-space planning and partial-order scheduling. We suggest that this general architecture may prove useful in other applications as more intelligent systems operate in continual, on-line settings. Our system has been used to drive several commercial prototypes and has enabled a new product architecture for our industrial partner. When compared with state-of-the-art off-line planners, our system is hundreds of times faster and often finds better plans. Our experience demonstrates that domain-independent AI planning based on heuristic search can flexibly handle time, resources, replanning, and multiple objectives in a high-speed practical application without requiring hand-coded control knowledge

Forecasting the effects of reduced defense spending

Forecasts from a vector autoregressive model indicate that the substantial cuts in defense spending proposed by the Bush Administration in 1991 are likely to reduce GNP in both the short run and the long run. These forecasts hold even if proceeds from the spending cuts are used to reduce the federal debt. The long-range VAR forecasts, in particular, contrast markedly with those of the large-scale econometric models employed by the Congressional Budget Office.Defense contracts

Forecasting the effects of reduced defense spending

Forecasts from a vector autoregressive model indicate that the substantial cuts in defense spending proposed by the Bush Administration in 1991 are likely to reduce GNP in both the short run and the long run. These forecasts hold even if proceeds from the spending cuts are used to reduce the federal debt. The long-range VAR forecasts, in particular, contrast markedly with those of the large-scale econometric models employed by the Congressional Budget Office.Defense contracts

Exchange Rate Pass-Through on Prices in Macrodata: A Comparative Sensitivity Analysis

The paper compares exchange rate pass-through on aggregate prices in the US, Germany and Japan across a number of dimensions. Building on the empirical approaches in the recent literature, our contribution is to perform a thorough sensitivity analysis of alternative pass-through estimates. We find that the econometric method, data frequency and variable proxy employed matter for the precision of details, yet they often agree on some general trends. Thus, pass-through on import prices has declined in the 1990s relative to the 1980s, pass-through on export prices remains country-specific and pass-through on consumer prices is nowadays negligible in all three economies we consider.

Regimes of waste (im)perceptibility in the life cycle of metal

The transnational legal landscape governing waste management, recycling, and disposal remains narrowly focused on the economic possibilities of ‘end-of-life products', while paying little to no consideration to the much greater quantities of waste generated at the beginning of the product's lifecycle. We explore the existing regulatory framework through the duality of (in)visibility: whereas the circular economy of recycling increasingly integrates synthetic waste into the visible, the extractive industry buries biophysical waste into a ‘cradle-to-grave' economy. We argue that waste becomes a perceptible matter of concern when commodified into a new cycle of wealth accumulation. By contrast, when waste is abandoned on mining sites, it becomes an imperceptible matter of fact. Mining risks, although perceptible to the industry and affected communities, are rendered less visible to the administrative bodies in charge of regulating them. Therefore, waste (im)perceptibility is industrially manufactured according to the commercial aspects of a product, rather than its toxicity

Egalitarianism against the Veil of Ignorance

J. Rawls and R. Dworkin have each used veils of ignorance to justify equality (Rawls) or to compute what equality entails (Dworkin). J. Harsanyi has also derived a distributive ethic from a veil of ignorance argument, which, although not egalitarian, is believed by Harsanyi to be not excessively inegalitarian. Harsanyi's analysis does not determine a unique social choice function, but rather a family of such functions. Here, by appending more information to Harsanyi's environment, and an Axiom of Neutrality, I uniquely determine a social welfare function by extending Harsanyi's argument. I show that this function is strongly inegalitarian, in that it recommends resource transfers from disabled to able individuals. Some concluding remarks are offered against using the veil of ignorance in studying the distributive ethics.Harsanyi, Dworkin, Rawls