Risks and threats to civilization, humankind, and the earth

This paper is a brief look at a wide range of risks that are said to present great threats to humankind. It was stimulated by several interacting factors. First, too many books and articles about astrophysical catastrophes, in the scientific and semi-scientific press, give relatively little attention to their timeframe or the measures to anticipate and prepare for them. Second, and most important, is that the overblown effects of 9/11 have distorted the United States of America's perspective and agenda on catastrophes. The result is that billions of dollars have been wasted and attention turned away from threats that could be truly catastrophic for the United States and, in many cases, for the rest of the world. Third, are books that have become popular by raising the threat that what will happen to us will be similar to what happened to earlier societies such as the Maya and the Easter Islanders. Most notably among these is Jared Diamond's Collapse [Jared Diamond, Collapse: How Societies Choose to Fail or Succeed, Penguin Group, 2005]. The failure in these doomsday arguments is to overlook the greater sophistication, knowledge, awareness, monitoring and preparation currently in the United States and in other parts of the globe. The institutional structure and scientific knowledge today would either prevent or deal with the kind of socio-economic decline anticipated by the “collapse” arguments. In contrast several geophysical and celestial risks do imply global catastrophe. The value of this paper is as broad background to the specific scenario papers that follow. While it leans heavily on the work of others, it offers three new features for the analysis of any extreme risk. First is a scale of devastation, based on deaths. Second is a comprehensive time frame—now to the end of the Earth. Third is an outline of general questions that must be addressed for any risk, however large or small, if it is to provide insight into policy choices and promote systemic thinking.     

Measuring Residential Real Estate Liquidity

There are many factors, other than price alone, that may affect the liquidity of real estate. This study develops a liquidity measure based on the Cox proportional hazard technique, a statistical model widely used in the epidemiologic and social sciences. The odds ratio, along with an estimate of market value for a home, are used to construct a liquidity measure. This measure can extract from the data a rich statistical profile of the variables that affect liquidity.     

Predicting Stock Returns Using Financial Statement Information

We examine the profitability of the Ou and Penman (1989a) Pr trading strategy and the Holthausen and Larcker (1992) Prob trading strategy over the period 1980–1992 in the UK. This is a test of whether an investor can earn abnormal returns by exploiting fundamental accounting data. We employ alternative abnormal return metrics and research designs to control for risk. Using a UK dataset offers an independent test because the UK differs from the US in its formal and informal financial reporting environment, its structure of share ownership, and the behaviour of its economy over the study period. We find consistent evidence that an investor could have used a summary measure of financial statement information to predict future abnormal returns by indirectly predicting one-year-ahead earnings changes, but only weak and inconsistent evidence that an investor could have used a summary measure of financial statement information to predict one-year-ahead stock returns directly. We offer some thoughts on the reasons for these different results.     

The allocative efficiency and conservation potential of water laws encouraging investments in on-farm irrigation technology

Agricultural water conservation statutes are emerging in the West encouraging private irrigators to improve on‐farm irrigation efficiency as a basinwide conservation measure. We investigate whether private improvements promote the economic efficiency and conservation of water use basinwide under a wide variety of hydroeconomic circumstances. The standard of efficiency is how an irrigation district manager should optimally invest in improving the irrigation efficiencies of individual farms located along a stream while internalizing intrabasin allocative externalities of these investments. The results indicate that the popular Oregon legislative model may be the least effective in conserving water and promoting economically efficient water allocation.