Nonparametric tests for strictly increasing virtual valuations

This paper shows that for absolutely continuous valuation distributions the increasing virtual valuations is equivalent to the increasing odds rate. Based on this new characterization we develop two nonparametric tests for the strictly increasing virtual valuations by using the generalized total time on test transform. The empirical type I error rate and power performance of the two tests are examined through Monte Carlo simulations. As illustrations the two tests are also applied to two real data sets collected from eBay.