'Cramer von Mises'

@cache_readonly
def wsqu(self):

    nobs = self.nobs
    cdfvals = self.cdfvals
    wsqu = (((cdfvals - ((((2.0 * np.arange(1.0, (nobs + 1))) - 1) / nobs) / 2.0)) ** 2).sum() + ((1.0 / nobs) / 12.0))
    return wsqu
