“…Test based on linear mixed model : The distance matrix can be transformed into a similarity matrix ( Vert et al , 2004 ) as, . When Y is a continuous outcome, G k can be incorporated in a linear mixed model framework, particularly popular in the context of heritability estimation ( Hoffman, 2013 ; Seal et al , 2022 ), as, where is the vector of fixed effects, is the vector of random effects following MVN( ) and ϵ is an error vector following MVN( 0 , The null hypothesis: can be tested using a LRT ( Crainiceanu and Ruppert, 2004 ). Note that, such a linear mixed model setup has been shown to be equivalent to a kernel machine regression framework by Liu et al (2008) .…”