Describing and explaining are two very different engagements, and yet development experts routinely write as though to describe were to explain. If this were not the case, it would be hard to understand why they have found it necessary to repeatedly describe the lives of the world’s poorest over the past 30 years. Consider the following sentence constructed from numerous writings—for example, b...

The American Medical Association’s Guides to the Evaluation of Disease and Injury Causation (Causation)1 is an important component of the AMA Guides library. This text delineates a type of evaluation that is distinctly different from a diagnostic evaluation, a treatment planning evaluation, a prognosis evaluation, or an impairment evaluation. It provides a protocol for determining whether a cli...

In practical applications, however, one is often confronted with the problem that the measurement errors which are quoted define a 68% confidence level interval around a Maximum Likelihood estimate, whereas one would need an unbiased estimator with its standard deviation in order to form a weighted average. In addition, one usually has to deal with statistical and systematic uncertainties, and ...