“…The GMM-ACH test uses the same setup as their GMM-test, but where the latter is based on Hansen's J-statistic the GMM-ACH tests is based on a sequence of LM statistics. Other approaches to testing the validity of a conditional moment restriction considers tests based on a marked empirical process and Kolmogorov-Smirnov or Cramér-von Mises statistics, see Stute (1997), Andrews (1997), Whang (2001), andVan Keilegom et al (2008), and tests based on nonparametric estimation, see Tripathi and Kitamura (2003). 1 Finally, the test proposed by Horowitz (2006) has a form similar to the ICM test, but uses a particular class of density functions for weighting instead of exponential functions.…”