For the short-ranged Lennard-Jones potential: the position errors of the new "quadrature rule" (QC-QR) and the cluster summation (QC-CS) approximations to the quasicontinuum method (left) and the percentage of particles used in calculations (right) versus the number of the representative particles. Here, r denotes the cluster radius in the QC-CS method; the larger the cluster radius, the more particles are involved in the assembly of the force balance equations and in the evaluation of the energy. We see that, relative to the the QC-CS method, for the same number of representative particles, the QC-QR has lower error and uses fewer particles, i.e., has lower complexity.