A Comparison of Four Models of Delay Discounting in Humans

The present study compared four prominent models of delay discounting: a one-parameter exponential decay, a one-parameter hyperbola (Mazur, 1987), a two-parameter hyperboloid in which the denominator is raised to a power (Green and Myerson, 2004), and a two-parameter hyperbola in which delay is raised to a power (Rachlin, 2006). Sixty-four college undergraduates made choices between hypothetical monetary rewards, one immediate and one delayed, and the fit of the four models to their data was assessed. All four equations accounted for a large proportion of the variance at both the group and the individual levels, but the exponents of both two-parameter models were significantly less than 1.0 at the group level, and frequently so at the individual level. Taken together, these results strongly suggest that more than one parameter is needed to accurately describe delay discounting by humans. Notably, both the Rachlin and the Green and Myerson models accounted for more than 99% of the variance at the group level and for 96% of the variance in the median individual. Because both models provide such good descriptions of the data, model selection will need to be based on other grounds

Revisiting Margaret Thatcher’s law and order agenda: The slow-burning fuse of punitiveness

In recent years, criminologists have devoted growing attention to the extent to which ‘punitiveness’ is emerging as a central feature of many criminal justice systems. In gauging punitiveness, these studies typically rely either on attitudinal data derived from surveys that measure individual support for punitive sentences or on the size of the prison population. We take a different approach, exploring the aims, content and outcomes of various Acts of Parliament passed between 1982 and 1998 in England and Wales. Our argument is that while a trend towards punitiveness is detectable, this was, in the case of England and Wales, attributable to wider discourses stemming from the New Right of the 1980s. This in turn promoted a new conception of how best to tackle rising crime. We show that while the year 1993 stands out as a key point in the growing trajectory of punitiveness in England and Wales, the ideas and rhetoric around ‘toughness’ in the criminal justice system can be traced back much further than this. Our article brings these matters to the attention of political scientists and demonstrates how historical institutionalist thinking can guide and inform interdisciplinary work at the interface between political science and criminology