newBlockX <- MASS::mvrnorm(sizePop[i], meanX, covX)
X <- rbind(X, newBlockX)
Y <- rbind(Y, t(apply(newBlockX, 1, function(row) MASS::mvrnorm(1, row %*%
newBlockX <- MASS::mvrnorm(sizePop[i], meanX, covX)
X <- rbind(X, newBlockX)
Y <- rbind(Y, t(apply(newBlockX, 1, function(row) MASS::mvrnorm(1, row %*%