TL;DR: In this article, the economic value of the European Centre for Medium-Range Weather Forecasts (ECMWF) operational ensemble prediction system (EPS) is assessed relative to the value of a perfect deterministic forecast.
Abstract: SUMMARY The economic value of the European Centre for Medium-Range Weather Forecasts (ECMWF) operational ensemble prediction system (EPS) is assessed relative to the value of a perfect deterministic forecast. The EPS has substantial relative value throughout the medium range. Probability forecasts derived from the EPS are of greater benefit than a deterministic forecast produced by the same model. Indeed, for many users, the probability forecasts have more value than a shorter-range deterministic forecast. Based on the measures used here, the additional information in the EPS (reflecting the uncertainty in the initial conditions) provides a benefit to users equivalent to many years’ development of the forecast model and assimilation system. The impact of ensemble size on forecast value is considered. The difference in performance between ensembles with 10 and with 50 members may appear relatively small, based on standard skill measures, yet the larger ensembles have substantial benefit to a range of users. Further increases in ensemble size may be. expected to provide additional value.
TL;DR: In this paper, a comparative analysis of possible postponement strategies in a two-stage decision model where firms make three decisions: capacity investment, production (inventory) quantity, and price is presented.
Abstract: This article presents a comparative analysis of possible postponement strategies in a two-stage decision model where firms make three decisions: capacity investment, production (inventory) quantity, and price. Typically, investments are made while the demand curve is uncertain. The strategies differ in the timing of the operational decisions relative to the realization of uncertainty. We show how competition, uncertainty, and the timing of operational decisions influence the strategic investment decision of the firm and its value. In contrast to production postponement, price postponement makes the investment and production (inventory) decisions relatively insensitive to uncertainty. This suggests that managers can make optimal capacity decisions by deterministic reasoning if they have some price flexibility. Under price postponement, additional postponement of production has relatively small incremental value. Therefore, it may be worthwhile to consider flexible ex-post pricing before production postponement reengineering. While more postponement increases firm value, it is counterintuitive that this also makes the optimal capacity decision more sensitive to uncertainty. We highlight the different impact of more timely information, which leads to higher investment and inventories, and of reduced demand uncertainty, which decreases investment and inventories. Our analysis suggests appropriateness conditions for simple make-to-stock and make-to-order strategies. We also present technical sufficiency and uniqueness conditions. Under price postponement, these results extend to oligopolistic and perfect competition for which pure equilibria are derived. Interestingly, the relative value of operational postponement techniques seems to increase as the industry becomes more competitive.
TL;DR: Results indicate not only that experienced value and decision value are represented in distinct regions of VMPFC, but also that decision value signals are evident even in the absence of an overt choice task.
Abstract: The core feature of an economic exchange is a decision to trade one good for another, based on a comparison of relative value. Economists have long recognized, however, that the value an individual ascribes to a good during decision making (i.e., their relative willingness to trade for that good) does not always map onto the reward they actually experience. Here, we show that experienced value and decision value are represented in distinct regions of ventromedial prefrontal cortex (VMPFC) during the passive consumption of rewards. Participants viewed two categories of rewards-images of faces that varied in their attractiveness and monetary gains and losses-while being scanned using functional magnetic resonance imaging. An independent market task, in which participants exchanged some of the money that they had earned for brief views of attractive faces, determined the relative decision value associated with each category. We found that activation of anterior VMPFC increased with increasing experienced value, but not decision value, for both reward categories. In contrast, activation of posterior VMPFC predicted each individual's relative decision value for face and monetary stimuli. These results indicate not only that experienced value and decision value are represented in distinct regions of VMPFC, but also that decision value signals are evident even in the absence of an overt choice task. We conclude that decisions are made by comparing neural representations of the value of different goods encoded in posterior VMPFC in a common, relative currency.
TL;DR: Six methods for collecting the judgments of experts concerning the relative value of sets of criteria were compared for their reliability and time efficiency, showing that ranking was by far the most efficient method.
Abstract: Six methods for collecting the judgments of experts concerning the relative value of sets of criteria were compared for their reliability and time efficiency. The methods were ranking, rating, thre...
TL;DR: In this article, the authors explore a new dimension of fund managers' timing ability by examining whether they can time market liquidity through adjusting their portfolios' market exposure as aggregate liquidity conditions change.