|  | ICOC elasticity |  | ||||
---|---|---|---|---|---|---|---|
 |  | OP costs |  | IP costs |  | Total costs |  |
OLS model | lag 1 year | -0.02 (0.004) | * | 0.08 (0.03) | ** | -0.01 (0.006) | *†|
 | lag 2 years | 0.01 (0.005) | †| 0.23 (0.03) | * | 0.04 (0.01) | * |
 | lag 3 years | 0.03 (0.005) | * | 0.22 (0.04) | * | 0.06 (0.007) | * |
2SLS model | lag1 year | 1.07 (0.21) | * | -23.32 (2.83) | * | -1.93 (0.32) | * |
 | Weak Instrument (Anderson-Rubin Wald test F) | 37.72 | * | 351.86 | * | 65.52 | * |
 | Wald test for endogeneity χ2(1) | 39.51 | * | 353.67 | * | 61.78 | * |
 | lag 2 years | -0.34 (0.18) |  | -12.07 (1.94) | * | -1.94 (0.34) | * |
 | Weak Instrument (Anderson-Rubin Wald test F) | 3.85 | †| 83.24 | * | 58.98 | * |
 | Wald test for endogeneity χ2(1) | 4.09 | †| 86.45 | * | 61.43 | * |
 | lag 3 years | -0.89 (0.22) | * | -0.20 (1.51) |  | -0.91 (0.31) | * |
 | Weak Instrument (Anderson-Rubin Wald test F) | 22.22 | * | 0.02 |  | 10.40 | * |
 | Wald test for endogeneity χ2(1) | 23.59 | * | 0.08 |  | 11.78 | * |