Figure 2From: A method to detect single-nucleotide polymorphisms accounting for a linkage signal using covariate-based affected relative pair linkage analysisObserved LR statistics and theoretical mixture distribution. The density of observed LR statistics from LOD scores using SNPs in noncausal genes is plotted. For the first model without a SNP covariate, the theoretical distribution is a 50:50 mixture of a chi-square distribution with 1 df and a chi-square distribution with 2 df because we have one covariate. For the second model with a SNP covariate, the theoretical distribution is a 50:50 mixture of a chi-square distribution with 2 df and a chi-square distribution with 3 df because we have two covariates. The blue curve is for the observed LR statistics; the black curve is for the theoretical values.Back to article page