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<u>Table 4. Estimated Equilibrium Bid Function: Road Sector</u>

||Linear|Quadratic|Log-|Non-|Linear|Quadratic|Log-|Non-|
|---|---|---|---|---|---|---|---|---|
||||linear|parametric|||linear|parametric|
|_N_|-0.52 <sup>***</sup>|-0.12|||-1.00 <sup>***</sup>|-1.61 <sup>**</sup>|||
||(0.09)|(0.63)|||(0.11)|(0.81)|||
|_N_ <sup>2</sup>||-0.02<br>||||0.03<br>|||
|||(0.03)||||(0.04)|||
|ln(_N_)|||-4.82 <sup>***</sup>||||-9.50 <sup>***</sup>||
||||(0.88)||||(1.23)||
|_N_=2||||8.57 <sup>**</sup>||||8.86 <sup>*</sup>|
|||||(3.39)||||(4.64)|
|_N_=3||||6.54 <sup>**</sup>||||16.93 <sup>***</sup>|
|||||<br>(2.92)||||<br>(3.93)|
|_N_=4||||6.37 <sup>***</sup>||||13.00 <sup>***</sup>|
|||||(1.98)||||(2.29)|
|_N_=5||||2.45 <sup>*</sup>||||8.76 <sup>***</sup>|
|||||(1.40)||||(1.81)|
|_N_=6||||2.94 <sup>**</sup><br>||||2.06<br>|
|||||(1.24)||||(1.82)|
|_N_=7||||1.39||||5.45 <sup>***</sup>|
|||||(1.50)||||(1.66)|
|_N_=8||||-0.53||||9.24 <sup>**</sup>|
|||||(2.41)||||(3.89)|
|_N_=9||||2.31||||10.11 <sup>***</sup>|
|||||(2.29)||||(3.07)|
|_N_=10||||4.56 <sup>***</sup>||||3.09 <sup>**</sup>|
|||||(1.57)||||(1.38)|
|_N_=11||||0.14||||-6.03|
|||||(4.56)||||(6.34)|
|Length|0.12|0.12|0.11|0.12|0.25 <sup>***</sup>|0.24 <sup>***</sup>|0.23 <sup>***</sup>|0.29 <sup>***</sup>|
||(0.08)|(0.08)|(0.08)|(0.08)|(0.09)|(0.09)|(0.09)|(0.09)|
|Length<sup>2</sup>1/|-0.41|-0.41|-0.39|-0.43|-0.65|-0.64|-0.61|-0.75|
||(0.40)|(0.40)|(0.40)|(0.43)|(0.45)|(0.45)|(0.45)|(0.47)|
|Lane|12.57 <sup>***</sup>|12.15 <sup>***</sup>|12.98 <sup>***</sup>|12.74 <sup>***</sup>|14.62 <sup>***</sup>|15.23 <sup>***</sup>|15.58 <sup>***</sup>|15.94 <sup>***</sup>|
||(1.86)|(2.04)|(1.97)|(2.27)|(2.12)|(2.41)|(2.27)|(2.57)|
|Lane<sup>2</sup>|-1.10 <sup>***</sup>|-1.06 <sup>***</sup>|-1.13 <sup>***</sup>|-1.10 <sup>***</sup>|-1.22 <sup>***</sup>|-1.28 <sup>***</sup>|-1.31 <sup>***</sup>|-1.30 <sup>***</sup>|
||(0.17)|(0.19)|(0.18)|(0.21)|(0.19)|(0.22)|(0.21)|(0.25)|
|_D_(New roads)|4.23|4.50|3.76|3.06|10.49 <sup>***</sup>|9.99 <sup>**</sup>|9.28 <sup>**</sup>|7.56 <sup>*</sup>|
||(3.17)|(3.17)|(3.18)|(3.40)|(4.02)|(4.13)|(4.05)|(4.12)|
|_D_(Rehabilitation work)|1.67|2.02|1.16|1.14|-0.65|-1.15|-1.72|-4.59|
||(2.14)|(2.19)|(2.16)|(2.62)|(3.18)|(3.38)|(3.24)|(3.50)|
|Engineering cost|0.53 <sup>***</sup>|0.53 <sup>***</sup>|0.52 <sup>***</sup>|0.54 <sup>***</sup>|||||
||(0.04)|(0.04)|(0.04)|(0.05)|||||
|Estimated duration|-0.30 <sup>***</sup>|-0.29 <sup>***</sup>|-0.31 <sup>***</sup>|-0.25 <sup>***</sup>|-0.09|-0.11|-0.12|-0.04|
||(0.07)|(0.07)|(0.08)|(0.08)|(0.08)|(0.09)|(0.09)|(0.11)|
|Donor 1|-6.48 <sup>**</sup>|-6.68 <sup>**</sup>|-6.13 <sup>**</sup>|-7.27 <sup>**</sup>|-6.06 <sup>*</sup>|-5.76|-5.35|-1.82|
||(2.58)|(2.65)|(2.53)|(3.22)|(3.69)|(3.79)|(3.67)|(4.00)|
|Constant|-1.67|-3.14|3.25|-9.71|-4.95|-2.66|5.27|-27.25 <sup>***</sup>|
||(4.50)|(4.43)|(4.40)|(5.75)|(6.13)|(6.27)|(6.10)|(6.80)|
|Obs.|394|394|394|394|394|394|394|394|
|R-squared|0.932|0.932|0.932|0.933|0.903|0.903|0.905|0.909|
|Number of dummies|||||||||
|Country|11|11|11|11|11|11|11|11|
|Bidder nationality|19|19|19|19|19|19|19|19|

1/ For presentation purposes, the coefficients are multiplied by 1,000. Note: The dependent variable is the bidding amount. The robust standard errors are shown in parentheses. *, ** and *** indicate the 10%, 5% and 1% significance levels, respectively.

Source: Author’s calculation.