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New product adoption in social networks: Why direction matters

Marketing managers and researchers generally agree that analyzing data from social networks and using them to influence consumers' purchase decisions are useful strategies. However, not all social network data may identify the most influential customers. This empirical study of more than 300 students reveals the low explanatory power of friendship networks (e.g., Facebook) and undirected-advice networks (e.g., LinkedIn). Only directed-advice networks (e.g., Google +) clearly identify influential consumers. In addition, the results challenge conventional wisdom that firms should target advisers assuming that they have the strongest influence on new product adoption. This study contradicts this common assumption and reveals that structural equivalence drives product adoption more than cohesion because advisees' adoption pressures advisers to purchase the product as well. Finally, the study shows the value of social network data beyond the traditional ego-centric psychographic metrics, such as innovativeness or opinion leadership.     

Economic Implications of Further Harmonisation of Electronic Communications Regulation in the EU

There are some aspects of the European RFEC and its implementation today that could benefit from increased harmonisation; there are others in which substantial accommodation to local, national or regional circumstances and preferences is desirable or required.     

The impact of traffic sign deficit on road traffic accidents in Nigeria

This study assesses the impact of traffic sign deficit on road traffic accidents in Nigeria. The participants were 720 commercial vehicle drivers. While simple random sampling was used to select 6 out of 137 federal highways, stratified random sampling was used to select six categories of commercial vehicle drivers. The study used qual-dominant mixed methods approach comprising key informant interviews; group interviews; field observation; policy appraisal and secondary literature on traffic signs. Result shows that the failure of government to provide and maintain traffic signs in order to guide road users through the numerous accident black spots on the highways is the major cause of road accidents in Nigeria. The study argues that provision and maintenance of traffic signs present opportunity to promoting safety on the highways and achieving the sustainable development goals.     

(Un)expected Bidder Behavior in Spectrum Auctions: About Inconsistent Bidding and Its Impact on Efficiency in the Combinatorial Clock Auction

The combinatorial clock auction is a two-stage auction format, which has been used to sell spectrum licenses worldwide in the recent years. It draws on a number of elegant ideas inspired by economic theory. A revealed preference activity rule should provide incentives to bid straightforward, i.e., consistent with the bidders’ valuations on a payoff-maximizing package, in each round of the clock phase. A second-price rule should set incentives to bid truthfully in both phases. If bidders respond to these incentives and bid straightforward in the clock phase and truthful in the second sealed-bid stage, then the auction is fully efficient. Unfortunately, bidders might neither bid straightforward in the clock phase nor truthful on all packages in the second sealed-bid stage due to strategic reasons or practical limitations. We introduce metrics based on Afriat’s Efficiency Index to analyze straightforward bidding and report on empirical data from the lab and from the field in the British 4G auction in 2013 and the Canadian 700 MHz auction in 2014, where the bids were made public. The data provides evidence that bidders deviate significantly from straightforward bidding in the clock phase, which can restrict the bids they can submit in the supplementary phase. We show that such restrictions can have a significant negative impact on efficiency and revenue.     

HIGH‐ORDER SHORT‐TIME EXPANSIONS FOR ATM OPTION PRICES OF EXPONENTIAL LÉVY MODELS

The short‐time asymptotic behavior of option prices for a variety of models with jumps has received much attention in recent years. In this work, a novel second‐order approximation for at‐the‐money (ATM) option prices is derived for a large class of exponential Lévy models with or without Brownian component. The results hereafter shed new light on the connection between both the volatility of the continuous component and the jump parameters and the behavior of ATM option prices near expiration. In the presence of a Brownian component, the second‐order term, in time‐t, is of the form , with d₂ only depending on Y, the degree of jump activity, on σ, the volatility of the continuous component, and on an additional parameter controlling the intensity of the “small” jumps (regardless of their signs). This extends the well‐known result that the leading first‐order term is . In contrast, under a pure‐jump model, the dependence on Y and on the separate intensities of negative and positive small jumps are already reflected in the leading term, which is of the form . The second‐order term is shown to be of the form and, therefore, its order of decay turns out to be independent of Y. The asymptotic behavior of the corresponding Black–Scholes implied volatilities is also addressed. Our method of proof is based on an integral representation of the option price involving the tail probability of the log‐return process under the share measure and a suitable change of probability measure under which the pure‐jump component of the log‐return process becomes a Y‐stable process. Our approach is sufficiently general to cover a wide class of Lévy processes, which satisfy the latter property and whose Lévy density can be closely approximated by a stable density near the origin. Our numerical results show that the first‐order term typically exhibits rather poor performance and that the second‐order term can significantly improve the approximation's accuracy, particularly in the absence of a Brownian component.     

Welfare Measurement and Measurement Error

The approximate effects of measurement error on a variety of measures of inequality and poverty are derived. They are shown to depend on the measurement error variance and functionals of the error–contaminated income distribution, but not on the form of the measurement error distribution, and to be accurate within a rich class of error–free income distributions and measurement error distributions. The functionals of the error–contaminated income distribution that approximate the measurement error induced distortions can be estimated. So it is possible to investigate the sensitivity of welfare measures to alternative amounts of measurement error and, when an estimate of the measurement error variance is available, to calculate corrected welfare measures. The methods are illustrated in an application using Indonesian household expenditure data.     

Training reflective processes in military aircrews through holistic debriefing: the importance of facilitator skills and development of trust

This paper explores how Holistic Debrief, a new concept in the field of debriefing and reflective processes, can contribute to restitution, reflection and learning in professional teams following stressful events and routine tasks. Interviews were conducted with Norwegian military aircrew mission commanders following deployment to Afghanistan in 2010. Phenomenological analysis in the frame of social learning theory revealed that reflective processes were easier to facilitate after stressful events than after routine tasks. Challenges identified included lack of trust during the early stages of team establishment and poor conceptual repertoires among aircrew commanders undertaking facilitation. Relational trust and reflective processes tended to improve after stressful events. Repeated interactions in Holistic Debrief tend to increase familiarity, trust and learning potential over time. This study reports data from the war context, an environment not often available for qualitative research. The findings are relevant for military and other operational units who wish to develop their debriefing practice and create an experience‐based learning environment.