Global developments in the competition for land from biofuels

The potential global demand for biofuels and the implications of this for land use and its interaction with food agriculture is reviewed. It is expected that biofuels will form an important element of global transport energy mix (in the order of 20–30% of total requirement) over the next 40 years and beyond. Over this time, there will be a transition from so called first generation biofuels, based on commodity agricultural crops with food/feed uses, to advanced biofuels, sometimes called second and third generation biofuels, based primarily upon lignocellulosic feedstocks. It remains unclear whether these advanced biofuels, based on lignocellulosic materials, will entirely replace first generation or if second generation will be supplemental to first generation. This expansion in biofuels will be coupled to a substantial increase in alternative fuels (electricity, hydrogen, biogas and natural gas) and modal shifts. Biofuel production from agricultural commodity crops that exhibit strong sustainability criteria will remain important (e.g. sugarcane) with supportive and competitive aspects for food security.Land requirement projections estimated for a range of potential biofuel development trajectories range widely and are inherently uncertain. Under the most active scenario that delivers substantive greenhouse gas reductions in transport by 2050 (relative to 2005 levels), approximately 100 Mha of additional land is projected. In the ‘business-as-usual’ scenario, in which transport energy demand rises by 80% by 2050 from present levels, a land use requirement of 650 Mha is projected.Significant potential exists for producing biofuels that possess high productivity and sustainability profiles through continued research, development and demonstration. Policy and regulation at a global level, that focuses biofuel development on these goals in ways that are synergistic with food agriculture, will simultaneously help to decarbonise transport and maintain a diverse and financially robust agricultural (and forestry) sector.     

Neural Networks for Forecasting: An Introduction

Neural networks are nonlinear mapping structures based on the study of the human brain. They have been shown to be universal and highly flexible junction approximators to any data-generating process. Therefore, they are powerful models for forecasting purposes, especially when the underlying data-generating processes are unknown. However, the appropriate design of the network's architecture and learning rules are crucial for obtaining satisfactory results. This study discusses the scope and limitations of neural networks for forecasting problems and provides an example by designing a neural network for forecasting. It is argued that statistical theory can offer some suggestions for designing an optimal network architecture. An example comparing a neural network and ARIM model for forecasting weekly corn prices 1974 through 1993 is provided. Results show the neural network model to be more accurate than the ARIMA.     

Against the trend: trade union growth in Northern Ireland

This paper analyses the dimensions and determinants of trade union growth in Northern Ireland. Aggregate membership, mostly in Great Britain-based unions, has grown more rapidly than the UK average in recent decades, largely due to a massive shift of employment into public sector services, where trade union density is higher.     

Demographic Change and Entrepreneurial Occupations: African Americans in Northern Cities

A bstract . In the early twentieth century, the African American (AA) populations of northern cities grew rapidly, whereas the foreign-born white populations of these cities stabilized. Stanley Lieberson has hypothesized that, in these cities, the resulting shifts in the ethnic composition negatively affected the economic prospects of AAs. The present study shows that the transformation of business enterprise among AAs in the urban North during 1900-1930 is consistent with this hypothesis. Census data and evidence from historical case studies suggest that the above demographic changes affected two trends: 1) a decline in the concentration of AAs in entrepreneurial occupations which served whites and 2) an increase in their concentration in entrepreneurial occupations serving other AAs.     

A Note on Ranking Real Estate Research Journals

An understanding of how thirty real estate journals are perceived for promotion and tenure and for professional applicability was sought by surveying members of the two most important real estate academic organizations. Several subgroup comparisons were made revealing some common perceptions but a significant amount of disagreement as well. Among findings robust across the surveyed community were that the Journal of the American Real Estate and Urban Economics Association (changed to Real Estate Economics in 1995) is the most important outlet for promotion and tenure and the Appraisal Journal is the most important outlet for professional applicability. Two distinct journal groupings emerged: an academic group composed of eight journals and a professional group of twenty.