 Also, in consequence, the CMA conducts an iterated principal components analysis of successful search steps while retaining "all" principal axes.Estimation of distribution algorithms and the Cross-Entropy Method are based on very similar ideas, but estimate (non-incrementally) the covariance matrix by maximizing the likelihood of successful solution "points" instead of successful search "steps".Second, two paths of the time evolution of the distribution mean of the strategy are recorded, called search or evolution paths.