Dari-Mattiacci, G. and Parisi, F. (2014). Returns to effort in rent-seeking games Public Choice, 159(1-2):99--104.

In the traditional formulation of rent-seeking games, increasing returns to effort are characterized by an exponent r>1. However, when the value of the rent is normalized to 1, the players{\textquoteright} effort levels A and B will typically be less than 1. Thus, when A<1 and r>1, the value of A r decreases as r increases, contradicting the interpretation of r>1 as representing increasing returns to effort. This apparent defect in the mathematization of the problem seems to suggest that a different interpretation of r is required whenever A<1, upsetting the uniformity and elegance of the model. In this short note, we demonstrate that the perceived problem is illusory, and that the usual interpretation of r is satisfactory for all values of A.