Indeterminacy in price–value correlation measures

During the last 20 years, an important body of literature on the so-called ‘Ricardo’s 93% theory of value’ – the classical hypothesis which asserts that direct prices are very good predictors of both production prices and market prices – has shown that the hypothesized strong correlation in fact holds in the context of cross-sectional data. However, these empirical results are extremely dubious due to severe problems that cause indeterminacy and arbitrariness in the measures of correlation usually employed.