variable | (1) Do not control the supplier | (2) lnCost | (3) lnCost |
Constant | 0.019*** | 0.019*** | 0.019*** |
(3.55) | (3.54) | (3.52) | |
lnRev | 0.941*** | 0.942*** | 0.942*** |
(66.38) | (66.34) | (66.43) | |
D | −0.033*** | −0.035*** | −0.034*** |
(−3.70) | (−3.85) | (−3.83) | |
lnRev * D | −0.195** | −0.235*** | −0.230*** |
(−2.54) | (−2.98) | (−2.93) | |
SP * lnRev * D |
| 0.023*** |
|
| (2.86) |
| |
SP * lnRev |
| 0.002 |
|
| (0.96) |
| |
SP * D |
| −0.006* |
|
| (−1.77) |
| |
SPSC * lnRev * D |
|
| 0.001*** |
|
| (2.84) | |
SPSC * lnRev |
|
| 0.000 |
|
| (0.68) | |
SPSC * D |
|
| −0.000** |
|
| (−2.38) | |
AI | −0.002 | −0.002 | −0.002 |
(−1.16) | (−1.16) | (−1.16) | |
AI * lnRev * D | 0.007 | 0.007 | 0.007 |
(0.85) | (0.87) | (0.84) | |
AI * lnRev | −0.023*** | −0.023*** | −0.023*** |
(−4.16) | (−4.14) | (−4.10) | |
AI * D | 0.010*** | 0.009*** | 0.009*** |
(3.32) | (3.27) | (3.28) | |
EI | −0.742*** | −0.749*** | −0.748*** |
(−2.68) | (−2.71) | (−2.70) | |
EI * lnRev * D | −5.445*** | −5.421*** | −5.388*** |
(−3.19) | (−3.18) | (−3.16) | |
EI * lnRev | 0.888 | 0.893 | 0.866 |
(0.96) | (0.97) | (0.94) |