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排序方式: 共有445条查询结果,搜索用时 15 毫秒
51.
52.
While organic food is based on well-defined production criteria, the criteria for ‘local’ food are less clear. This study investigates the preferences and trade-offs of distinct consumer segments relative to organic production and several dimensions of local food (sales channel, size of company, and geographical location of animals used in the production). The analysis is based on a quantitative survey of 505 Danish consumers and a choice experiment involving beef salami. Data were analyzed in a principal component and a latent class analysis. We identify five consumer segments whose preferences for organic and local product attributes differed substantially. Most respondents considered geographical proximity in the raising of cattle to be the most important attribute and a third of the consumers were willing to pay a premium for organic salami. The segmentation provides more detailed information about stated consumer behavior than what is typically elicited when considering only average consumer behavior.  相似文献   
53.
Abstract

Aims: To evaluate total costs and health consequences of a colorectal cancer (CRC) screening program with colonoscopy, fecal immunochemical tests (FIT), and expanded use of multitarget stool DNA (mt-sDNA) from the perspectives of Integrated Delivery Networks (IDNs) and payers in the United States.

Materials and methods: We developed a budget impact and cost-consequence model that simulates CRC screening for eligible 50- to 75-year-old adults. A status quo scenario and an increased mt-sDNA scenario were modeled. The status quo includes the current screening mix of colonoscopy (83%), FIT (11%), and mt-sDNA (6%) modalities. The increased mt-sDNA scenario increases mt-sDNA utilization to 28% over 10 years. Costs for both the IDN and the payer perspectives incorporated diagnostic and surveillance colonoscopies, adverse events (AEs), and CRC treatment. The IDN perspective included screening program costs, composed of direct nonmedical (e.g. patient navigation) and indirect (e.g. administration) costs. It was assumed that IDNs do not incur the costs for stool-based screening tests or bowel preparation for colonoscopies.

Results: In a population of one million covered lives, the 10-year incremental cost savings incurred by increasing mt-sDNA utilization was $16.2 M for the IDN and $3.3 M for the payer. The incremental savings per-person-per-month were $0.14 and $0.03 for the IDN and payer, respectively. For both perspectives, increased diagnostic colonoscopy costs were offset by reductions in screening colonoscopies, surveillance colonoscopies, and AEs. Extending screening eligibility to 45- to 75-year-olds slightly decreased the overall cost savings.

Limitations: The natural history of CRC was not simulated; however, many of the utilized parameters were extracted from highly vetted natural history models or published literature. Direct nonmedical and indirect costs for CRC screening programs are applied on a per-person-per modality basis, whereas in reality some of these costs may be fixed.

Conclusions: Increased mt-sDNA utilization leads to fewer colonoscopies, less AEs, and lower overall costs for both IDNs and payers, reducing overall screening program costs and increasing the number of cancers detected while maintaining screening adherence rates over 10 years.  相似文献   
54.
Anomalies in the Foundations of Ridge Regression   总被引:1,自引:0,他引:1  
Errors persist in ridge regression, its foundations, and its usage, as set forth in Hoerl & Kennard (1970) and elsewhere. Ridge estimators need not be minimizing, nor a prospective ridge parameter be admissible. Conventional estimators are not LaGrange's solutions constrained to fixed lengths, as claimed, since such solutions are singular. Of a massive literature on estimation, prediction, cross–validation, choice of ridge parameter, and related issues, little emanates from constrained optimization to include inequality constraints. The problem traces to a misapplication of LaGrange's Principle, unrecognized singularities, and misplaced links between constraints and ridge parameters. Alternative principles, based on condition numbers, are seen to validate both conventional ridge and surrogate ridge regression to be defined. Numerical studies illustrate that ridge regression as practiced often exhibits pathologies it is intended to redress.  相似文献   
55.
This article argues that Danish flexicurity is preconditioned by craft unionism that has historically been predominant in the Danish trade union movement. It is furthermore argued that flexicurity was on the verge to disappear when it became famous in the early 2000s, although yet not completely dead.  相似文献   
56.
In the classical portfolio optimization problem considered by Merton, the resulting constant proportion investment plan requires a diffusive trading strategy. This means that, within any arbitrarily small time interval, the investor must impractically both buy and sell stocks. We study the problems of a mean-square and a power utility investor for whom the trading strategy is constrained to be smooth, i.e. nondiffusive. This means that over sufficiently small time intervals, the investor is either a seller or a buyer of stocks. The mathematical framework is built around quadratic objectives such that trading activity is punished quadratically. Mean-square utility is quadratic, and power utility is covered by quadratic punishment of distance to Merton’s power utility portfolio. We present semi-explicit solutions and, in a series of numerical illustrations, show the impact of trading constraints on the portfolio decision over the investment horizon.  相似文献   
57.
This study aims to analyze what drives and prevents the purchasing of eco-friendly products across different consumer groups and develops a conceptual model embracing the positive altruistic (care for the environmental consequences of purchasing), positive ego-centric (green self-identity and moral obligation), and negative ego-centric (perceived personal inconvenience of purchasing eco-friendly products) antecedents of eco-friendly product purchase intention and behavior. We empirically validate the conceptual model for green (n = 453) and non-green (n = 473) consumers (i.e., consumers who engage in a set of pro-environmental behaviors for environmental reasons versus consumers who do not engage in these behaviors). Data are analyzed using structural equation modeling and multi-group analysis of the two groups. The results confirm the relevance of the determining factors in the model and show significant differences in eco-friendly product purchasing patterns between green and non-green consumers. Altruistic motives are more important for green than for non-green consumers. Negative ego-centric motives affect the purchase intentions of non-green consumers more than the intentions of green consumers, whereas the impact of negative motives on behavior is stronger for green than for non-green consumers. The first contribution of this paper is the development and testing of a parsimonious model of eco-friendly products purchasing that embraces both positive (altruistic and ego-centric) and negative (ego-centric) antecedents, which have been theoretically suggested in the past but have rarely been empirically tested together. The second contribution of this study is that it develops insight into the specific antecedents of eco-friendly products purchasing for green and non-green consumers to assess potential similarities and differences in eco-friendly products purchasing process, the hypothesized antecedents, their impact on eco-friendly products purchase intention and behavior, and the intention–behavior relation.  相似文献   
58.
A small group of academics and practitioners discusses four major controversies in the theory and practice of corporate finance:
  • • What is the social purpose of the public corporation? Should corporate managements aim to maximize the profitability and value of their companies, or should they instead try to balance the interests of their shareholders against those of “stakeholder” groups, such as employees, customers, and local communities?
  • • Should corporate executives consider ending the common practice of earnings guidance? Are there other ways of shifting the focus of the public dialogue between management and investors away from near-term earnings and toward longer-run corporate strategies, policies, and goals? And can companies influence the kinds of investors who buy their shares?
  • • Are U.S. CEOs overpaid? What role have equity ownership and financial incentives played in the past performance of U.S. companies? And are there ways of improving the design of U.S. executive pay?
  • • Can the principles of corporate governance and financial management at the core of the private equity model—notably, equity incentives, high leverage, and active participation by large investors—be used to increase the values of U.S. public companies?
  相似文献   
59.
This article reviews recent developments in China’s agricultural domestic support policy, especially the transition from taxing farmers and agriculture to providing direct subsidies to grain production and purchased inputs. A model‐based quantitative analysis on the effects of these policy changes is presented. Simulation results suggest that recent policy changes have achieved the declared policy goals of increasing grain production and boosting farm income. Much of the increase in grain production and farm income can be attributed to higher per unit return to arable land, land reallocation to grain production and extra agricultural employment triggered by the policy changes. Based on the assumption that China’s public assistance to agriculture and farmers will continue and rise, two hypothetical future scenarios are simulated. Using all the support permitted under WTO de minimis limits with existing instruments, China’s policy will increase grain production, change trade patterns seemingly contrary to China’s comparative advantage, increase rural employment and significantly increase farm income (by more than 12%). If, however, decoupled instruments are applied to raise China’s agricultural domestic support to the same level, China’s agricultural production and trade will remain unchanged, rural employment remain stable, but farm income will be increased by nearly 15%.  相似文献   
60.
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