This paper presents a review of adaptation concepts at the evolutionary, environmental, neural, sensory, mental and mathematical levels, including Helson’s and Parducci’s theories of perception and category judgments. Two kinds of adaptation can be clearly distinguished. The first, known as...

In its present formulation the Human Development Index (HDI) is a measure of the well-being of nations considering two fixed reference values for each indicator, the so-called fixed goals of development, as normalization parameters. As is well known, the HDI is insensitive to the relative...