你有在做收敛相关的研究吗？请参考最近 Kongy, J., Phillips, P. C. B., and Sul, D. (2017), "Weak $\sigma$-Convergence: Theory and Applications." Working paper. 其提供 Stata (Gauss) code:  http://www.utdallas.edu/~d.sul/papers/Recent%20Working%20Papers1.htm 。