Generalized fiducial methods for testing quantitative trait locus effects in genetic backcross studies

Abstract

In this paper, we propose generalized fiducial methods and construct four generalized p-values to test the existence of quantitative trait locus effects under phenotype distributions from a location-scale family. Compared with the likelihood ratio test based on simulation studies, our methods perform better at controlling type I errors while retaining comparable power in cases with small or moderate sample sizes. The four generalized fiducial methods support varied scenarios: two of them are more aggressive and powerful, whereas the other two appear more conservative and robust. A real data example involving mouse blood pressure is used to illustrate our proposed methods.

Keywords

• generalized fiducial inference
• quantitative trait locus
• mixture model
• gibbs algorithm
• likelihood ratio test