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381.
Identification of skill sets required of managers and supervisors in livestock production is necessary to guide selection, training, task assignment, and promotion. Management roles in livestock production differ from those in other industries, given the unique work environment and task attributes of production agriculture. Based on focus group discussions with pork operation managers, iterative code development resulted in five management skill sets: Change Agent, Counselor, Model Employee, Motivator, and Housekeeper. These skill sets were compared with a data set of dairy operation managers and with research in other industries based on the Competing Values Framework for managerial leadership.  相似文献   
382.
In recent years, parastatal grain marketing boards have re‐emerged as important elements of grain markets in eastern and southern Africa, yet little is known about how farmers are responding to their scaled up activities. This article develops a conceptual model of farmers’ production decisions in the context of dual output marketing channels (government and private sector) when output prices at harvest time and the availability of one of the marketing channels are unknown at planting time. It then applies the model to the case of Zambia and uses nationally representative household‐level panel survey data to estimate the effects of the Food Reserve Agency (FRA), the government parastatal maize marketing board, on smallholder crop production and fallow land. The FRA buys maize from smallholders at a pan‐territorial price that typically exceeds market prices in major maize producing areas. Results suggest that increases in the farmgate FRA maize price raise farmer maize price expectations, which induces a supply response. Smallholders respond to an increase in the FRA price by extensifying their maize production. On average, a 1% increase in the FRA price is associated with 0.06% increases in smallholders’ maize area planted and quantity harvested. There is also some evidence that farmers reduce the area of land under fallow in response to FRA incentives but there is no evidence of reductions in the area planted to other crops.  相似文献   
383.
PORTFOLIO OPTIMIZATION WITH JUMPS AND UNOBSERVABLE INTENSITY PROCESS   总被引:2,自引:0,他引:2  
We consider a financial market with one bond and one stock. The dynamics of the stock price process allow jumps which occur according to a Markov-modulated Poisson process. We assume that there is an investor who is only able to observe the stock price process and not the driving Markov chain. The investor's aim is to maximize the expected utility of terminal wealth. Using a classical result from filter theory it is possible to reduce this problem with partial observation to one with complete observation. With the help of a generalized Hamilton–Jacobi–Bellman equation where we replace the derivative by Clarke's generalized gradient, we identify an optimal portfolio strategy. Finally, we discuss some special cases of this model and prove several properties of the optimal portfolio strategy. In particular, we derive bounds and discuss the influence of uncertainty on the optimal portfolio strategy.  相似文献   
384.
385.
Aim: Progel Pleural Air Leak Sealant (Progel) is currently the only sealant approved by the FDA for the treatment of air leaks during lung surgery. This study was performed to determine whether Progel use improves hospital length of stay (LOS) and hospitalization costs compared with other synthetic/fibrin sealants in patients undergoing lung surgery.

Methods: The US Premier hospital database was used to identify lung surgery discharges from January 1, 2010 to June 30, 2015. Eligible discharges were categorized as “Progel Sealant” or “other sealants” using hospital billing data. Propensity score matching (PSM) was performed to control for hospital and patient differences between study groups. Primary outcomes were hospital LOS and all-cause hospitalization costs. Clinical outcomes, hospital re-admissions, and sealant product use were also described.

Results: After PSM, a total of 2,670 discharges were included in each study group; baseline characteristics were balanced between groups. The hospital LOS (mean days?±?standard deviation, median) was significantly shorter for the Progel group (9.9?±?9.6, 7.0) compared with the other sealants group (11.3?±?12.8, 8.0; p?<?.001). Patients receiving Progel incurred significantly lower all-cause hospitalization costs ($31,954?±?$29,696, $23,904) compared with patients receiving other sealants ($36,147?±?$42,888, $24,702; p?<?.001).

Limitations: It is not possible to say that sealant type alone was responsible for the findings of this study, and analysis was restricted to the data available in the Premier database.

Conclusions: Among hospital discharges for lung surgery, Progel use was associated with significantly shorter hospital LOS and lower hospitalization costs compared with other synthetic/fibrin sealants, without compromising clinical outcomes.  相似文献   
386.
While prior ecolabel research suggests that consumers’ trust of ecolabel sponsors is associated with their purchase of ecolabeled products, we know little about how third-party certification might relate to consumer purchases when trust varies. Drawing on cognitive theory and a stratified random sample of more than 1200 consumers, we assess how third-party certification relates to consumers’ use of ecolabels across different program sponsors. We find that consumers’ trust of government and environmental NGOs to provide credible environmental information encourages consumers’ use of ecolabels sponsored by these entities, and consumers do not differentiate between certified versus uncertified ecolabels in the presence of trust. By contrast, consumers’ distrust of private business to provide credible environmental information discourages their use of business association-sponsored ecolabels. However, these ecolabels may be able to overcome consumer distrust if their sponsors certify the ecolabels using third-party auditors. These findings are important to sponsors who wish develop ecolabels that are more credible to consumers, and thus encourage more widespread ecolabel use.  相似文献   
387.
International Entrepreneurship and Management Journal - The present research proposes a theoretical framework for a thrivable entrepreneurial ecosystem in which thrivability is a novel...  相似文献   
388.
Recent scholarship on technological change highlights its negative impacts on employment and wages. However, a decade of nationally representative surveys show that Americans hold favorable views toward technology despite concerns over labor displacement. How do people cope with employment threats from a trend they consider desirable? Using a survey experiment, this paper argues that people opt to buffer domestic workers from technological threats with substitute policies against outgroups that they believe could improve wages and employment prospects. Specifically, direct cues about technological displacement make Republicans more likely to demand tighter restrictions on immigration and Democrats more likely to support higher tariffs. In other words, citizens respond to automation anxiety by blaming and penalizing groups that they consider unwelcome or objectionable, depending on their partisanship. Respondents remained reluctant to express support for technological restrictions. Thus, automation anxiety may intensify resistance to globalization, but not necessarily technology.  相似文献   
389.
Decisions in Economics and Finance - This paper draws a parallel between the economic and financial points of view in the modeling of long-term yield curves and provides new results on asymptotic...  相似文献   
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