Table:
province-state
economic region

column 1
column 2
column 3
column 4

canada-united states border

coefficient
-1.435
-1.555
-1.568
-1.434

robust standard error
0.370
0.531
0.187
0.243

provincial border

coefficient
..
..
-0.576
-0.785

robust standard error
..
..
0.126
0.127

state border

coefficient
..
..
-0.387
-0.301

robust standard error
..
..
0.049
0.048

intra-regional flows
yes
no
yes
no

number of observations
3,364
3,306
40,401
40,200

Statement: the economic region regressions are able to simultaneously measure state borders of -0.387 when internal flows are included.
Question: what is the effect of the economic region regressions are able to simultaneously measure state border effects when internal flows are included?
Answer: [-0.387]