'Estimating' numbers? A response to a paper by Samuel A. Hardy

Samuel A. Hardy (2017) has recently attempted a wide-ranging comparison of the efficacy of different kinds of regulating metal detecting. Based on a comparison of 12 countries with partially different regulatory regimes, he arrives at the conclusion that liberal regulatory approaches are less effective than restrictive ones in keeping the numbers of metal detectorists low and thus reducing damage to archaeological evidence. According to Hardy, the regulatory systems in England and Wales, and the USA, work particularly badly in preventing archaeological damage.

In this paper, I demonstrate that his study is seriously methodically flawed. While Hardy uses a reasonably consistent methodology to estimate the minimum number of metal detectorists in 10 of the countries he examines, he deviates massively from this for England and Wales, and the USA, creating estimates for the actual number of detectorists. These different kinds of estimates, he then directly compares.

I thus argue that Hardy’s (2017) study, its results, and the conclusions he draws from them, sadly must be discarded. Instead of creating a sound empirical comparison of comparable data, Hardy has manipulated data to arrive at a preconceived conclusion.