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.