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71.
The “Masters Hypothesis” is the claim that unprecedented buying pressure in recent years from commodity index investors created massive bubbles in food and energy prices. The purpose of this article is to review the evidence from recent studies that investigate the empirical relationship between index investment and price movements in agricultural futures markets. One line of research uses time‐series regression tests, such as Granger causality tests, to investigate the relationship between price movements and index positions. This research provides little evidence in support of the Masters Hypothesis in agricultural futures markets. A second line of research uses cross‐sectional regression tests and studies in this area provide very limited evidence in favor of the Masters Hypothesis for agricultural futures markets. A third line of research investigates whether there is a significant relationship between commodity index trading and the difference, or spread, between futures prices of different contract maturities on the same date. These studies report a range of results depending on the type of test. However, the bulk of the evidence indicates either no relationship or a negative relationship, which is once again inconsistent with the Masters Hypothesis. Overall, this growing body of literature fails to find compelling evidence that buying pressure from commodity index investment in recent years caused a massive bubble in agricultural futures prices. The Masters Hypothesis is simply not a valid characterization of reality.  相似文献   
72.
A rapidly growing number of households are suffering from energy impoverishment caused by escalating electricity prices, low income, and poor housing energy efficiency. Many households are experiencing considerable hardship in paying energy bills. This manifestation of inequality has followed the global restructuring of electricity sectors, and its incidence has become widespread across Europe, the UK, the US, New Zealand, and Australia. Current policy measures generally resemble "retrospective compensation" rather than addressing the root cause of the problem. This paper argues for a new policy approach that reconfigures electricity price formation in order to address this increasingly embedded social phenomenon.  相似文献   
73.
Conventional procedures for calculating confidence limits of forecasts generated by statistical models provide little guidance for forecasts based on a combination or a consensus process rather than formal models, as is the case with US Department of Agriculture (USDA) forecasts. This study applied and compared several procedures for calculating empirical confidence intervals for USDA forecasts of corn, soybean and wheat prices over the 1980/81 through 2006/07 marketing years. Alternative procedures were compared based on out-of-sample performance over 1995/96 through 2006/07. The results of this study demonstrate that kernel density, quantile distribution and best fitting parametric distribution (logistic) methods provided confidence intervals calibrated at the 80% level prior to harvest and 90% level after harvest. The kernel density-based method appears most accurate both before and after harvest with the final value falling inside the forecast interval 77% of the time before harvest and 92% after harvest, followed by quantile regression (73% and 91% before and after harvest, respectively) logistic distribution (73% and 90% before and after harvest, respectively) and histogram (66% and 84% before and after harvest, respectively). Overall, this study demonstrates that empirical approaches may be used to construct more accurate confidence intervals for USDA corn, soybean and wheat price forecasts.  相似文献   
74.
Decision Neuroscience   总被引:2,自引:0,他引:2  
This article presents an introduction to and analysis of an emerging area of research, namely decision neuroscience, whose goal is to integrate research in neuroscience and behavioral decision making. The article includes an exposition of (1) how the exponential accumulation of knowledge in neuroscience can potentially enrich research on decision making, (2) the range of techniques in neuroscience that can be used to shed light on various decision making phenomena, (3) examples of potential research in this emerging area, and (4) some of the challenges readers need to be cognizant of while venturing into this new area of research. The genesis of this workshop session and article was a meeting that Dipankar Chakravarti, Antoine Bechara, and Baba Shiv had one balmy Iowa City summer afternoon in 2003. We coined the term Decision Neuroscience to describe the emerging stream of research outlined in this article.  相似文献   
75.
Abstract

In this article, we express a concern that certain commonly accepted methods of predicting mortality will likely prove to be inadequate in the future. Specifically, the Lee-Carter method, which overall has been empirically successful, uses auto-regressive moving average (ARMA) technology and contains no structural mortality equation. This structure means that no information other than previous history can be introduced. We argue that rapid advances in medical science are taking place and that failure to reflect this information in our projection methodology will make resulting projections unsuitable.  相似文献   
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Surveying Farmers: A Case Study   总被引:1,自引:0,他引:1  
A large percentage of farmers do not respond to mail surveys. To gain insight into why farmers do not respond and how to improve response rates, a three-step research design was developed. First, an initial survey, based on in-person interviews with 15 farmers, was sent to 100 farmers. Second, farmers who did not respond to this mail survey were contacted by phone to investigate the reasons for not responding. Third, based on the information from these nonrespondents, the survey instrument was revised and sent to 3,990 U.S. farmers. Our studies show that the period in which the survey is sent is a crucial factor in the willingness to participate, along with the form and amount of compensation, the sender of the questionnaire, and the perceived length of the questionnaire.  相似文献   
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