*-------------
*-2.2.3 范例
*--
*-数据形态
use product.dta, clear
xtset state year
xtdes
des
sum
*--
*-权重矩阵
clear all
spmat use usaww using "usaww.spmat" //调入权重矩阵
spmat sum usaww, links detail //描述性分析
spmat graph usaww // 48*48, 图形呈现
spmat graph usaww, blocks(4) // 12*12
spmat export usaww using USA_W.txt, replace //输出为 txt 文档
shellout USA_W.txt
*--
*-回归分析
use product.dta, clear
gen lngsp = log(gsp)
gen lnpcap = log(pcap)
gen lnpc = log(pc)
gen lnemp = log(emp)
global xx "lnpcap lnpc lnemp unemp" //解释变量
*-SAR (Spatial Autoregression)
xsmle lngsp $xx, wmat(usaww) fe
est store SAR