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131.
Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.  相似文献   
132.
Predicting the geo-temporal variations of crime and disorder   总被引:2,自引:0,他引:2  
Traditional police boundaries—precincts, patrol districts, etc.—often fail to reflect the true distribution of criminal activity and thus do little to assist in the optimal allocation of police resources. This paper introduces methods for crime incident forecasting by focusing upon geographical areas of concern that transcend traditional policing boundaries. The computerised procedure utilises a geographical crime incidence-scanning algorithm to identify clusters with relatively high levels of crime (hot spots). These clusters provide sufficient data for training artificial neural networks (ANNs) capable of modelling trends within them. The approach to ANN specification and estimation is enhanced by application of a novel and noteworthy approach, the Gamma test (GT).  相似文献   
133.
This article matches establishment-level data on workplace transformation (e.g., quality circles, work teams, and just-in-time production) with measures of cumulative trauma disorders at these same establishments to explore the relationship between "flexible" workplace practices and workplace health and safety. The results reveal a positive, statistically significant, and quantitatively sizable relationship between cumulative trauma disorders and the use of quality circles and just-in-time production.  相似文献   
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A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
136.
For a compound Poisson process with negative drift and jump distribution consisting of a mixture of exponentials on [0) and on (-, 0), an exact expression is derived for the probability of hitting the level c, c > 0. the problem is motivated by modeling the returns from trading on financial markets.  相似文献   
137.
Borda's vote method was used by the French Academy from 1796 to 1803 when Napoleon got it abolished. In the laws and regulations of the Academy there are stipulations regarding the election of new members. The practice is demonstrated by some examples from the protocols. In fact, Borda presented two vote methods which he showed would give the same conclusion. The method which has not been in the limelight proves to be the same one as is used for selecting the best player in chess tournaments.  相似文献   
138.
A negative relationship between corporate leverage and tax shields has been predicted because a large nondebt tax shield reduces the expected value of interest tax savings and lessens the advantage of debt financing. Previous studies, however, have provided inconclusive and contradictory evidence on whether nondebt tax shields crowd-out debt financing. The analysis herein relies on unique constructs of discounted depreciation tax shields and presents evidence that crowding-out does not occur. Furthermore, it is shown that contradictory inferences may result from analysis of annual tax depreciation deductions instead of discounted tax shields. The findings suggest that firms with substantial cash flow from depreciation exploit their higher debt capacity by maintaining a capital structure with significantly more debt than otherwise.  相似文献   
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