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961.
This paper utilizes calculated historical volatility and GARCH models to compare the historical price volatility behavior
of crude oil, motor gasoline and heating oil in U.S. markets since 1990. We incorporate a shift variable in the GARCH/TARCH
models to capture the response of price volatility to a change in OPEC’s pricing behavior. This study has three major conclusions.
First, there was an increase in volatility as a result of a structural shift to higher crude oil prices after April 1999.
Second, volatility shocks from current news are not important since GARCH effects dominate ARCH effects in the variance equation.
Third, persistence of volatility in all commodity markets is quite transitory, with half-lives normally being a few weeks.
相似文献
Thomas K. LeeEmail: |
962.
货币激励的非连贯性以及次优性 总被引:4,自引:0,他引:4
货币激励是使用最广泛的激励方式之一。关于货币激励的负效应,虽然国内实务界已有所经验认识,但学术界的深入定量讨论甚少。本文运用实验经济学的方法,研究比较了在不同情况下货币激励、非货币物质激励以及零激励三者之间的关系。本文研究结果表明货币激励在大额激励和小额激励两种情况下都是次优的选择:在小额激励的情况下,货币激励会有负面作用,降低人们的行为动机和行为绩效;在大额激励的情况下,货币激励的作用不及同等价值的非货币物质激励。在实验分析后,本文给出了相关的理论和解释,包括内在动机的挤出效应、非完全合同、边际效应递减等,并提出了在实践中可以借鉴的方法。 相似文献
963.
Germano Mwabu Mwangi S. Kimenyi Paul K. Kimalu Nancy Nafula Damiano Kulundu Manda 《Revue africaine de developpement》2003,15(1):77-85
Household surveys provide data that is used for identifying and measuring the poverty status of households and individuals. However, carrying out such surveys is expensive, especially in poor developing countries. Thus it is important to make maximum use of the available survey data in developing countries, especially in sub‐Saharan Africa, where such data are expensive to collect and analyse. This paper develops a simple method for using poverty indices derived from survey data for a given year, to predict poverty rates for subsequent periods without having to conduct a new household survey. We illustrate the workings of the method with data from Kenyan household surveys for 1994 and 1997. 相似文献
964.
Standard practice in the residential mortgage underwriting industry is to estimate collateral values via independent appraisals conducted by third parties. This paper empirically examines the role of property value ( i.e. , appraisal) uncertainty as a determinant of default on residential mortgage loans. Based upon an analysis of 1,428 residential loans drawn from the portfolio of a national mortgage lender, we find evidence that semivariance in property value uncertainty is related to default risk. Specifically, subject properties that are valued above the sales price of recently sold "similar and proximate" properties show evidence of greater default risk. Interestingly, a variance (range) measure of property value uncertainty is not significantly related to default risk. 相似文献
965.
Risky Business or Competitive Power? Supplier Involvement in Japanese Product Design 总被引:10,自引:0,他引:10
Notwithstanding the alleged risks of outsourcing design work, leading manufacturers in the Japanese automotive industry collaborate closely with their key suppliers. Despite widespread recognition of the effectiveness of these close-knit supplier networks, however, little research exists on the factors that affect the purchase of design work from suppliers. S. Nazli Wasti and Jeffrey K. Liker fill this gap by exploring the factors that affect Japanese automotive firms' purchase of design work from their component suppliers. Using data from a survey of 122 Japanese automotive component suppliers, their study addresses two key questions. First, what factors lead Japanese buyers to involve some suppliers heavily in design while giving others relatively little control over design decisions? And second, does the Japanese practice of involving suppliers in design offer performance benefits? The study focuses on first-tier suppliers of parts, assemblies, and complete subsystems (e.g., audio, fuel and emissions, heating and air conditioning). The study does not include suppliers of raw materials and chemicals, assembly and processing equipment, indirect materials, tooling and dies, computers and software, or engineering and business consulting services. The study breaks down the broad concept of supplier involvement in design work into three measurable elements: the extent to which the supplier influences decision-making during the early stages of product development; the amount of control the buyer retains over the design; and the frequency of design-related communication between the buyer and the supplier. Factors that have a positive effect on the level of supplier involvement among the companies studied include technological uncertainty of the component and the supplier's in-house technical capabilities. For companies in the study, the level of competition in the supplier market has a negative effect on the degree of supplier involvement in design. The responses indicate that supplier involvement offers performance benefits for both the supplier and the buyer. For the supplier firms studied, increased involvement in the design process permits greater focus on design for manufacturability (DFM). And of course, supplier-generated design improvements clearly benefit the buyers, allowing these firms to capitalize on the experience and the insight that their suppliers have regarding the parts that they supply. 相似文献
966.
This study uses data on intra-day transactions to analyze whether real estate investment (REIT) liquidity as measured by the bid-ask spread changed from 1990 to 1994, a period during which the industry's market capitalization increased from $8.7 billion to $45 billion. REIT percentage spreads (spread as percentage of share price) narrowed significantly, primarily attributable to higher share prices rather than narrower dollar-value spreads. An empirical model is used to analyze the determinants of percentage spreads. Return variance and share price, not market capitalization are found to be the primary determinants of percentage spreads in both periods. This suggests that the liquidity of REIT securities is similar to that of non-REIT securities with similar prices and return variance. In addition, percentage spreads are wider for REITs trading on the NASDAQ. 相似文献
967.
968.
Resource‐based theory maintains that intrinsic characteristics of resources and capabilities, such as their tacitness, complexity, and specificity, prevent imitation and thereby prolong exceptional performance. There is little direct evidence to verify these claims, yet a substantial literature encourages firms to formulate competitive strategies around resources with these attributes. Further, work outside the resource‐based tradition suggests that these attributes can slow innovation, and it is not clear when this effect outweighs the benefits of inimitability. This paper seeks to clarify whether and how the complexity, tacitness, and specificity of a firm's knowledge affect the persistence of its performance advantages. We find that the complexity and tacitness of technological knowledge are useful for defending a firm's major product improvements from imitation, but not for protecting its minor improvements. The design specificity of technological knowledge delayed imitation of minor improvements in this study. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
969.
Rudy K. Moenaert Dirk Deschoolmeester Arnoud De Meyer William E. Souder 《R&D Management》1992,22(1):021-040
Abstract The research question in the present article can be phrased in the following way: what are the elements which influence the perception of the utility of information received from another function? A field study research has been conducted in 40 Belgian companies. In each company, we have studied two on-going innovation projects (one planning project, one development project). Crossfunctional communication behaviours at the R&D/marketing interface have been measured by means of mailed structured questionnaires. Three-hundred and eighty-six questionnaires have been returned. The data analyses show that there are four underlying information dimensions, i.e. the perceived relevance, the perceived comprehensibility, the perceived novelty and the perceived credibility of information. We also discuss some contingency variables (function of the message receiver, stage in the innovation process) that might moderate the impact of these dimensions. It will be shown that the interaction between source and receiver has a significant impact on the perceived credibility, the perceived comprehensibility and the perceived novelty of the received information. 相似文献
970.
An Infant Feeding Practices Study (IFPS) in 1982 in Kenya, which included a cross-sectional survey of a weighted sample of 980 low and middle income Nairobi mothers who had given birth in the previous 18 months, found that most women breastfeed their infants for long periods, but many introduce alternate feeding, especially infant formula, in the 1st 4 months (86 and 50% of the infants were breastfed at 6 and 15 months respectively, but 50% of the 2 month-olds and 63% of the 4 month-olds were receiving substitutes, mostly formula). This is done largely out of the belief that infant formula is an additional health benefit. A workshop to discuss the findings of the IFPS and other available data, and to make policy recommendations urged the adoption of a policy of protection, support and promotion of breastfeeding. Since breastfeeding is already widely prevalent in Kenya, protection of breastfeeding should receive the 1st priority in policy related to infant feeding. Attention should be directed at at least 2 influences which help undermine breastfeeding: widespread availability and promotion of breast milk substitutes. Support for breastfeeding is viewed as the 2nd policy priority. Situations where support can play a helpful role are, women's paid employment outside the home, hospital practices, maternal morbidity, and difficulties in breastfeeding. Since promotion is the least cost effective of the 3 options, and most Kenyan women are already motivated to breastfeed, this should be the last priority. Promotion includes reeduction of mothers to make them better aware of the benefits of breastfeeding. The workshop recommended the dissemination of appropriate information, consisting of standarized messages based on clearcut guidelines, using mass media techniques. 相似文献