*****《工业机器人对中国企业参与国际循环的影响》*****
****************************************************
****表2 基准回归结果
use 表2.dta,clear
global Firm_Control "leverage fin Scale age ex" 
global City_Control "gdp pop stru open"	 
ppmlhdfe exgvcgl robexposure ,a(fid year) vce(cluster cid)
ppmlhdfe exgvcgl robexposure $Firm_Control, a(fid  year) vce(cluster cid)
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control, a(fid year) vce(cluster cid)
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control, a(fid year cid) vce(cluster cid)
****表3 联合固定效应
use 表3-1.dta,clear
global Firm_Control "leverage fin Scale age ex" 
global City_Control "gdp pop stru open"	 
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control, a(fid year cid region_year) vce(cluster cid) 
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control, a(fid year cid hy_dq) vce(cluster cid) 
****表3 工具变量
use 表3-2.dta,clear
ivreghdfe exgvcgl $Firm_Control $City_Control (robexposure=iv1) ,a(fid year cid) 
ivreghdfe exgvcgl $Firm_Control $City_Control (robexposure=iv2) ,a(fid year cid)
***表5 稳健性检验
use 表4.dta,clear
ppmlhdfe plvgvc_f robexposure $Firm_Control $City_Control, a(fid year cid) vce(cluster cid)
reghdfe exgvcgl robexposure $Firm_Control $City_Control, a(fid year cid) 
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if year!=2008,a(fid year cid) vce(cluster cid)
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control internet,a(fid year cid) vce(cluster cid)
ppmlhdfe exgvcgl robexposure imr $Firm_Control $City_Control, a(fid year cid) 
***表5 要素密集度异质性
use 表5.dta,clear
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if 要素密集度==1,a(fid year cid) vce(cluster cid) 
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if 要素密集度==2,a(fid year cid) vce(cluster cid)
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if 要素密集度==3,a(fid year cid)  vce(cluster cid) 
ppmlhdfe exgvcgl robexposure rob_lab $Firm_Control $City_Control ,a(fid year cid) vce(cluster cid)
***表6
use 表6.dta,clear
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if dist==1,a(fid year cid) vce(cluster cid) 
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if dist==2 | dist==3,a(fid year cid) vce(cluster cid) //
ppmlhdfe exgvcgl robexposure robme $Firm_Control $City_Control ,a(fid year cid) vce(cluster cid) //
***表7
use 表7.dta,clear
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if lp<lp_75, a(fid year cid) 
ppmlhdfe exgvcgl robexposure $Firm_Control $City_Control if lp>lp_75 ,a(fid year cid) 
ppmlhdfe exgvcgl robexposure rob_lp lp $Firm_Control $City_Control ,a(fid year cid) 
***表8列（1）
use 机制检验1.dta,clear
global City_Control "gdp pop stru open"	 
reghdfe lntrca robexposure $City_Control ,a(year cid hyid) vce(cluster cid)
***表8列（2）
use 机制检验2.dta,clear
global City_Control "gdp pop stru open"	 
reghdfe lnis robexposure $City_Control ,a(year cid) 
***表8列（3）
use use 机制检验3.dta,clear
global Firm_Control "leverage fin Scale age ex" 
global City_Control "gdp pop stru open"	 
ppmlhdfe 一般贸易 robexposure $Firm_Control $City_Control ,a(fid year cid) vce(cluster cid)
***表9
use 拓展性分析.dta,clear
global City_Control "gdp pop stru open"	 
ppmlhdfe inn robexposure i,a(cid year hyid) vce(cluster cid)
ppmlhdfe inn robexposure $City_Control ,a(cid year hyid) vce(cluster cid)
ppmlhdfe inn robexposure $City_Control ,a(cityhy year ) vce(cluster cid)

