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81.
To reduce the competition from farmers who self-produce seed, an inbred line seed producer can switch to nondurable hybrid seed. In a two-period framework, we first investigate the impact of crop durability on self-production, pricing and switching decisions. Second, we study how the introduction of a fee paid by self-producing farmers affects those decisions. We find that the monopolist may produce technologically dominated hybrid seed in order to extract more surplus from farmers. Further, the introduction of a self-production fee improves efficiency.  相似文献   
82.
Research on location-based advertising (LBA) suggests that the merits of LBA lie in the fact that consumers can be targeted with location-congruent ads on their personal mobile devices. However, LBA consists of two underlying constructs: a mobile (vs. point-of-sales) advertising medium and location congruency (vs. location incongruency). This study aims to disentangle these underlying constructs by showing that they differentially affect the efficacy of an ad. Using a virtual reality lab experiment, this study shows that location-congruent ads result in increased choice for the target brand as compared to location-incongruent ads, independent of medium type. However, in location-incongruent situations, mobile ads attracted more attention than point-of-sales display ads. The advantages of LBA thus do not seem to emanate from medium type, but rather from the congruency between the ad and product location. When the ad is received at a different location than the product, the mobile medium is able to enhance consumers' ad attention.  相似文献   
83.
The digital transformation of the healthcare branch is important and unstoppable. The enormous possibility of digitalisation to redesign and enhance processes has been shown in other branches. Digital technologies offer the similarly large potential to improve the quality and efficiency of healthcare services. However, in terms of digitalisation, the German health system lags behind other European countries. But given a lack of available evidence, the effects of the digitalisation of the healthcare system cannot be reliably evaluated. Digital access to patient data necessitates constructive error cultures in organisations in order to limit defensive medicine. And digital access to health information necessitates individual competence in searching and using this information for participatory decision-making. As with all technological progress, information security is very important in order to gain citizens’ confidence in a digital healthcare system. Thus, it is necessary to simultaneously pursue both enhanced privacy standards and state-of-the-art medical technology.  相似文献   
84.
The purpose of this paper is to show the varying effects of alliance portfolio size and heterogeneity on innovation in biotechnology firms. Previous literature has indicated that the number and heterogeneity of partners in an alliance portfolio might have positive effects on innovativeness. Yet, engaging in multiple and heterogeneous collaborations also raises managerial costs and complexity levels disproportionally, potentially causing detrimental performance effects. Analysis of a unique panel dataset suggests that engaging in many alliances generally has a positive influence on a firm’s innovation output. Furthermore, maintaining diverse alliance portfolios and a high extent of alliancing jointly affects a firm’s innovation output ?negatively. By additionally showing that younger firms benefit disproportionally from both alliance portfolio diversity and size, this study provides a more nuanced view of alliancing effects.  相似文献   
85.
Increased engagement with mobile apps is an emerging trend with people today. Mobile devices have become so personalized that many people consider their mobile device as an extension of themselves. Research has suggested that one driving factor in a person’s adoption of mobile apps is the pursuit of happiness. However, there is little research regarding the influence of apps on a person’s well-being. The purpose of this paper was to examine mobile app usage among college students and the relationship between app usage and one’s satisfaction with life. Findings suggest that there is a correlation between mobile app usage and a person’s level of satisfaction with life. Gender differences in app usage were also found.  相似文献   
86.
Global leaders agree on the need to substantially decarbonize the global economy by 2050. This paper compares potential costs associated with different policy pathways to achieve tourism sector emission reduction ambitions (?50% by 2035) and transform the sector to be part of the mid-century decarbonized economy (?70% by 2050). Investment in emissions abatement within the tourism sector, combined with strategic external carbon offsets, was found to be approximately 5% more cost effective over the period 2015–2050 than exclusive reliance on offsetting. The cost to achieve the ?50% target through abatement and strategic offsetting, while significant, represents less than 0.1% of the estimated global tourism economy in 2020 and 3.6% in 2050. Distributed equally among all tourists (international and domestic), the cost of a low-carbon tourism sector is estimated at US$11 per trip, equivalent to many current travel fees or taxes. Exclusive reliance on offsetting would expose the sector to extensive and continued carbon liability costs beyond mid-century and could be perceived as climate inaction, increasing reputational risks and the potential for less efficient regulatory interventions that could hinder sustainable tourism development. Effective tourism sector leadership is needed to develop a strategic tourism policy framework and emission measurement and reporting system.  相似文献   
87.
A framework for the detection of change points in the expectation in sequences of random variables is presented. Specifically, we investigate time series with general distributional assumptions that may show an unknown number of change points in the expectation occurring on multiple time scales and that may also contain change points in other parameters. To that end we propose a multiple filter test (MFT) that tests the null hypothesis of constant expectation and, in case of rejection of the null hypothesis, an algorithm that estimates the change points.The MFT has three important benefits. First, it allows for general distributional assumptions in the underlying model, assuming piecewise sequences of i.i.d. random variables, where also relaxations with regard to identical distribution or independence are possible. Second, it uses a MOSUM type statistic and an asymptotic setting in which the MOSUM process converges weakly to a functional of a Brownian motion which is then used to simulate the rejection threshold of the statistical test. This approach enables a simultaneous application of multiple MOSUM processes which improves the detection of change points that occur on different time scales. Third, we also show that the method is practically robust against changes in other distributional parameters such as the variance or higher order moments which might occur with or even without a change in expectation. A function implementing the described test and change point estimation is available in the R package MFT.  相似文献   
88.
89.
Learning is often a central element of tourism. Tourists can learn actively, i.e. with a specific purpose, as well as passively through the comparison of values, norms and customs. It has been argued that travel supports active learning that has positive outcomes for sustainability, for instance, in the context of conservation. Yet, the complexity of active and passive learning processes and their outcomes for environmental sustainability and sustainable lifestyles remain insufficiently understood. Against this background, the paper discusses selected learning outcomes for transportation (air travel), accommodation (hotels) and activities (theme park visits). Findings suggest that “desirable” learning (defined as pro-sustainable development learning) in tourism may be very limited, while in particular, passive learning processes which redefine social norms frequently have outcomes that are largely detrimental to sustainable lifestyles. They include forms of moral licensing, the diffusion of responsibilities as well as the attenuation of the negative consequences of travel. Given the economic, social and cultural importance of tourism vís-a-vís its global implications for environmental sustainability, learning outcomes in tourism deserve to be studied in greater detail, while strategies need to be devised to enhance sustainable learning effects.  相似文献   
90.
In the second half of 2009, the entire media agenda in Germany was dominated by the swine flu, next to the German Federal Parliament elections. Criticism was voiced in the media against the pharmaceutical industry for lobbying the nationwide swine flu vaccination, which was widely considered nothing but a product of the industry’s lobbying power. In order to avoid the usual interviews with lobbyists, we attempted to apply a new methodological framework approach in analysing lobbying processes and key stakeholders in the public sphere—and outside. Crucial to the diversified approach, which involves quantitative content analysis of media coverage and press releases, are interviews with journalists, lobbyists’ network analysis and internet research on biographies. Although a conspiracy could not be conclusively proven, the results do indicate associations that validate the criticism of the industry’s lobbying activities.  相似文献   
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