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971.
Feenstra H Ruiter RA Schepers J Peters GJ Kok G 《International journal of injury control and safety promotion》2011,18(3):181-187
Adolescents are at a greater risk of being involved in traffic accidents than most other age groups, even before they start driving cars. This article aims to determine the factor structure of a self-report questionnaire measuring adolescent risky cycling behaviour, the ACBQ (Adolescent Cycling Behaviour Questionnaire). The questionnaire's structure was based on the widely used Driver Behaviour Questionnaire (DBQ). A sample of secondary school students (N?=?1749; age range: 13-18 years) filled out the questionnaire. Factor analysis revealed a three-factor structure underlying the questionnaire, which was confirmed on two equally large portions of the entire sample. These three underlying factors were identified as errors, common violations and exceptional violations. The ACBQ is a useful instrument for measuring adolescents' risky cycling behaviour. 相似文献
972.
973.
Estimating the cost of liquidity in agricultural futures markets is challenging because bid‐ask spreads are usually not observed. Based on an ability to reflect simulated data from Roll's spread model, we assess the effectiveness of conventional and Bayesian bid‐ask spread estimators under different market conditions. Conventional serial covariance and absolute price change spread estimators appear to be biased. Hasbrouck's Bayesian estimator generates small costs of liquidity whose values depend on the correlation and noise in the data. The absolute value Bayesian estimator is precise and works well under conditions of high levels of noise and correlation usually found in agricultural futures markets. Using data from live cattle (LC) and lean hog (LH) contracts, we find similar patterns of performance that produce economically meaningful cost of liquidity differences. 相似文献
974.
This study addresses the issue of the relative degree of variance in ROA accounted for by industry, corporate, and SBU effects while controlling for the business cycle and the interaction between the business cycle and industry. Two key articles, Schmalensee (1985) and Rumelt (1991), are discussed in detail. Research results on a recent data base (COMPUSTAT), using variance components analysis (VARCOMP) are presented that not only confirm most of the Rumelt (1991) findings, but also suggest the existence of a corporate effect, heretofore undetected. 相似文献
975.
LOUIS A. THOMAS 《战略管理杂志》1996,17(6):481-498
Large sunk investments in advertising allow managers to credibly preempt potential entrants by introducing new products prior to anticipated increases in market growth. Previous investment in advertising can lower a firm's cost to introduce new products allowing it to credibly preempt potential entrants. Entrants may not have enough residual share to find it profitable to enter later, and incumbents find it profitable to keep new products in the market even if entrants choose to enter. I present empirical evidence from the RTE cereal industry. 相似文献
976.
A major component of the United States Environmental Protection Agency's 112(r) Risk Management Program Rule is the evaluation and control of potential public exposures to toxic chemicals. The rule requires identification and evaluation of a worst case accidental toxic release scenario, but provides for the inclusion of passive mitigation systems in modeling the dispersion hazard zones that are to be communicated to the public. These passive mitigation systems can be taken into account in the consequence modeling if they will withstand the initiating event that causes the accidental release and function as intended. This paper discusses several passive mitigation systems that can be designed as an integral part of storage or processing of highly toxic chemicals. These include, but are not limited to, optimizing storage conditions, design of secondary containment, toxic vapor generation control, and enclosure design. The effectiveness of various passive mitigation systems is evaluated using consequence modeling for case studies involving highly toxic chemicals such as phosgene, chlorine, and ethylene oxide. 相似文献
977.
978.
979.
980.
Mark A. White 《Business Strategy and the Environment》1996,5(3):198-206
Environmental issues are restructuring markets and redirecting capital flows throughout the world. An outline is provided of concerns facing the development of an environmentally responsible or ‘environmental finance’ perspective. It reviews the major ways in which organizations are responding to environmental threats and opportunities in the three major branches of finance — corporate finance, investments and financial institutions — highlighting in particular novel programs and initiatives. In the past, financial concerns have exacerbated the degradation of the natural environment; in the future, they probably hold the key to their preservation. 相似文献