 In a 2015 article in the American Economic Review " Papers and Proceedings " , the economist Paul Romer decried " Mathiness in the Theory of Economic Growth " . Romer claims that mathematics is progressive in economics when it is rigorous and when the mathematical variables have a clear relationship to actual and plausibly measurable aspects of the economy . He writes that in growth theory today , both aspects are frequently missing and that the resulting use of mathematics is merely mathiness . 
