BACKGROUND A recent paper presents an argument and mechanism for the possible stopping of clinical trials early based on opportunity costs. DISCUSSION Although we agree that the costs and opportunity costs of clinical trials need to be reduced wherever possible, we raise concerns about the motivation and mechanism for stopping clinical trials early raised by Lavery et al. SUMMARY We argue t...

Nature reserves are often designated ad hoc. Despite increasing conservation efforts, loss of biodiversity is still accelerating. Considering land scarcity and demand for alternative uses, efficiency in conservation strongly correlates with efficiency in land allocation. Systematic conservation planning can effectively prioritize conservation activities. Previous studies minimize opportunity co...

Generating companies use the maintenance cost function as the sole or main objective for creating the maintenance schedule of power generators. Usually only maintenance activities related costs are considered to derive the cost function. However, in deregulated markets, maintenance related costs alone do not represent the full costs of generators. This paper models various cost components that ...

Improved governance and lower start-up costs may not be sufficient for encouraging the type of entrepreneurship that matters for economic growth. Using panel data on 60 countries spanning the period 2003-07 this paper establishes that (i) opportunitymotivated entrepreneurship (as opposed to necessity-motivated entrepreneurship) drives economic growth; (ii) governance and the start-up costs are ...

The opportunity costs associated with the provision of informal care are usually estimated based on the reduced potential of the caregiver to partake in paid work (both in terms of whether they are able to undertake paid work, and if so the hours of work undertaken). In addition to the hours of informal care provided, these opportunity costs are also likely determined by the necessity to perfor...

A spate of recent work demonstrates that humans seek to avoid the expenditure of cognitive effort, much like physical effort or economic resources. Less is clear, however, about the circumstances dictating how and when people decide to expend cognitive effort. Here we adopt a popular theory of opportunity costs and response vigor and to elucidate this question. This account, grounded in Reinfor...

BACKGROUND Many low and middle income countries have developed community health strategies involving lay health workers, to complement and strengthen public health services. This study explores variations in costing parameters pertinent to deployment of community health volunteers across different contexts outlining considerations for costing program scale-up. METHODS The study used quasi exp...