Test Statistic Use this option to select the test statistic to use for evaluating significance of QTL components. Available test statistics are described in the table below: Select When you want to: Likelihood Ratio Determine the likelihood ratio statistic of the restricted versus the full model . Wald Determine the Wald statistic for each marker's additive effect variance component. To Specify the Test Statistic: Select the desired test statistic by clicking within the appropriate radio button.