why is lmer used as matrix which matrix is needed for variance in lmer? lmer variance matrix which matrix is used in an r variable? what is the matrix of variance in lmer what is the variance coefficient matrix in r what is the variance coefficient matrix in lmer lmer functions does r use lmer function what is the matrix of variance in r? when using lmer r function what are variance coefficients what is variance matrix is lmer linear function what is lmer used for what is the function of lmer in r lmer matrix lmer what is the variance variance matrix what is the matrix of variance in lmer variance matrix what is the variance coefficient matrix in r