Establishing the validity of cycle path capacity assumptions in the Highway Capacity Manual

Cycle mode share increase is widely desired, but highway design practitioners lack the numerical tools to deliver infrastructure, instead relying on design standards and intuition, with little literature basis. As a case in point, the US Highway Capacity Manual (which is well used internationally) has developed levels of service for cycle infrastructure that are, at their core, based on an assumption of noninteraction between multiple cyclists. This paper uses a modified implementation of the Social Force Model to test the validity of this assumption. Necessary changes such as the consideration of acceleration characteristics and minimum maintainable speed are included. The resulting model produces valid outcomes in keeping with established traffic flow properties, reflecting three-phase traffic flow theory and the ability for the stochastic elements in traffic flow to cause flow breakdown. The developed simulation indicates that there is a fundamental difference in outcome if cyclists are assumed to have a fixed speed versus one they can change given their surroundings. This difference in outcomes is found to exist within the range of literature design flow capacities for bicycle infrastructure and also yields emergent outcomes that align closely with those known behaviors of highway vehicles, which intuitively transfer to cyclists. These findings reinforce the standing need for large-scale empirical studies to determine the basic numerical and behavioral parameters for cyclists, upon which all design ultimately rests.     

Proximity and animal welfare in the context of tourist interactions with habituated dolphins

The long-term sustainability of wildlife tourism depends on integrating visitor demands with resource management, requiring an understanding of tourist motivation. Managing the conflict between access to the animals and welfare, however, may diminish the experience for tourists. This paper identifies trade-offs tourists are willing to make between access and animal welfare, associated with feeding habituated bottlenose dolphins (Tursiops sp.) in Monkey Mia, Western Australia. Using a choice modelling technique, we were able to determine monetary values of visitor experiences. Compared to the current guaranteed interaction with dolphins (and a daily resort entrance fee), respondents were willing to pay significantly higher hypothetical entrance fees to avoid a decrease in proximity to, or probability of, the dolphin interaction. However, negative impacts on dolphin welfare had a negative impact on visitor utility. Over 80% of visitors (n = 244) accepted management regulations resulting in decreased time with and proximity to dolphins, if those addressed welfare concerns and were communicated clearly. Thus, while visitors placed the greatest value on the proximity and predictability, they were willing to trade off these aspects if they improved dolphin welfare. We provide management suggestions based on these results.     

An integrated approach for ex-ante evaluation of public policies for sustainable agriculture at landscape level

An integrated methodological framework for ex-ante evaluation and planning of public policies for sustainable agriculture at agro-landscape level is proposed. The components of the framework are to: (1) determine the private, i.e. farmers’, and public benefits associated to agro-landscapes, consisting of an agricultural land-use system, according to its performance for several market and non-market functions. Market forces determine the market benefits and preferences of society the non-market benefits; (2) explore and select potential sustainable agro-landscapes based on the private and public benefits associated with possible land-use alternatives; (3) define efficient public policy mechanisms for improving social net benefit of agro-landscapes.The framework is illustrated with a case study in a small dairy farming dominated agro-landscape in The Netherlands, with gross margin, landscape quality, nature value and environmental health as the analysed ecosystem functions. Alternative landscapes consisting of hedgerow configurations and grassland management practices were explored, yielding a set of alternatives representing the solution space in terms of change in private and public benefits. Policy mechanisms were defined to move from the current to a desired landscape based on changes in social net benefits. Moreover, the necessity of a modification in the current agri-environmental support was analysed for each landscape. The analysis considered all farmers in the agro-landscape jointly. The results for the case study showed potential prototypes of landscapes and their performance compared to the current landscape. Extension was the most efficient policy mechanism to promote the change to the socially optimum landscape alternative.     

Assessing the Impact of the ‘Decoupling’ Reform of the Common Agricultural Policy on Irish Farmers’ Off‐farm Labour Market Participation Decisions

This paper assesses the impact of the ‘decoupling’ reform of the Common Agricultural Policy on the labour allocation decisions of Irish farmers. The agricultural household decision‐making model provides the conceptual and theoretical framework to examine the interaction between government subsidies and farmers’ time allocation decisions. The relationship postulated is that ‘decoupling’ of agricultural support from production would probably result in a decline in the return to farm labour but it would also lead to an increase in household wealth. The effect of these factors on how farmers allocate their time is tested empirically using labour participation and labour supply models. The models developed are sufficiently general for application elsewhere. The main findings for the Irish situation are that the decoupling of direct payments is likely to increase the probability of farmers participating in the off‐farm employment market and that the amount of time allocated to off‐farm work will increase.     

Design efficiency for non‐market valuation with choice modelling: how to measure it,what to report and why*

We review the basic principles for the evaluation of design efficiency in discrete choice modelling with a focus on efficiency of WTP estimates from the multinomial logit model. The discussion is developed under the realistic assumption that researchers can plausibly define a prior belief on the range of values for the utility coefficients. D‐, A‐, B‐, S‐ and C‐errors are compared as measures of design performance in applied studies and their rationale is discussed. An empirical example based on the generation and comparison of fifteen separate designs from a common set of assumptions illustrates the relevant considerations to the context of non‐market valuation, with particular emphasis placed on C‐efficiency. Conclusions are drawn for the practice of reporting in non‐market valuation and for future work on design research.     

Pricing equity options everywhere

Finite difference methods are a popular technique for pricing American options. Since their introduction to finance by Brennan and Schwartz their use has spread from vanilla calls and puts on one stock to path-dependent and exotic options on multiple assets. Despite the breadth of the problems they have been applied to, and the increased sophistication of some of the newer techniques, most approaches to pricing equity options have not adequately addressed the issues of unbounded computational domains and divergent diffusion coefficients. In this article it is shown that these two problems are related and can be overcome using multiple grids. This new technique allows options to be priced for all values of the underlying, and is illustrated using standard put options and the call on the maximum of two stocks. For the latter contract, I also derive a characterization of the asymptotic continuation region in terms of a one-dimensional option pricing problem, and give analytic formulae for the perpetual case.     

Research on e-commerce transaction networks using multi-agent modelling and open application programming interface

We provide a formal definition of an e-commerce transaction network. Agent-based modelling is used to simulate e-commerce transaction networks. For real-world analysis, we studied the open application programming interfaces (APIs) from eBay and Taobao e-commerce websites and captured real transaction data. Pajek is used to visualise the agent relationships in the transaction network. We derived one-mode networks from the transaction network and analysed them using degree and betweenness centrality. Integrating multi-agent modelling, open APIs and social network analysis, we propose a new way to study large-scale e-commerce systems.     

Cost-effectiveness of a continuous glucose monitoring system with trending and rate information to predict hypoglycaemia and hyperglycaemia in pregnant women with insulin-dependent diabetes mellitus

Summary

This study seeks to determine the cost-effectiveness of the FreeStyle Navigator? continuous glucose monitoring system compared with self-monitoring of blood glucose (SMBG) when predicting hypoglycaemia and hyperglycaemia in pregnant women with insulin-dependent diabetes mellitus. A Markov model was constructed, and initial model analysis demonstrates that use of the FreeStyle Navigator? by a patient who is trained in diabetes management is more cost-effective than SMBG, resulting in an incremental cost-effectiveness ratio of $267 per quality-adjusted life-month ($3,204 per quality-adjusted life-year). The real-time glucose level rate of change and trend information provided by the FreeStyle Navigator? allows appropriately trained patients to improve upon decisions regarding self-treatment to prevent hypoglycaemic and hyperglycaemic episodes, resulting in a lower treatment cost and higher effectiveness than untrained patients. Based on current performance attributes, a device such as the FreeStyle Navigator? would be more cost-effective than other glucose-monitoring devices, meeting the $50,000/QALY willingness-to-pay threshold used by payers for adoption of new technology.     

Computer Simulation as a Tool for Planning and Management of Visitor Use in Protected Natural Areas

The United Nations Environment Programme’s Principles on Implementation of Sustainable Tourism suggest that implementing sustainable tourism must include monitoring visitor use of protected natural areas and directing it to areas where the environmental and social impacts of tourism are minimised. Thus, sustainable tourism management requires information about the spatial and temporal flow of visitor use in protected natural areas to help identify potential tourism-related threats to the natural and cultural resources of an area and the quality of visitors’ experiences. Recent research has identified at least four ways in which simulation modelling of visitor use can facilitate more informed planning and management of sustainable tourism in protected natural areas, including (1) describing existing visitor use flows; (2) monitoring the condition of ‘hard to measure’ indicator variables; (3) testing the effectiveness of alternative visitor use management practices; and (4) guiding the design of research on public attitudes. The purpose of this paper is to demonstrate, using findings from studies conducted in the Inyo National Forest and Isle Royale National Park, USA, each of these four potential contributions of computer simulation to sustainable tourism management and planning. The paper concludes with an assessment of the limitations of existing applications of computer simulation to nature-based tourism and recommendations for future research.     

A support methodology for EAI and BPM projects in SMEs

This paper presents a support methodology that facilitates the analysis of shared information between applications. The contemporary needs of information systems within companies rely on the integration of different applications. As a consequence, integration projects called EAI (enterprise application integration) and BPM (business process management) have arisen. These projects need support methodologies to facilitate the process of information integration. The aforementioned methodology also helps companies to align management applications with their business processes and to define the integration of the company's information systems.