Geography Reference
In-Depth Information
Table 15
.
2
Rare events logit models of the likelihood of a focal patent receiving a
citation from a future patent*
Model 1
Model 2
Model 3
Model 4
k
0.863•••
(0.257)
−1.599•
(0.644)
−1.305••
(0.378)
k
2
−0.203•••
(0.086)
1.116•••
(0.209)
1.051•••
(0.156)
k
×
Close collaboration
3.242•
(1.670)
4.327••
(1.659)
k
2
×
Close collaboration
−3.428•••
(0.708)
−4.881•••
(0.725)
k
×
Far collaboration
1.569••
(0.573)
1.899••
(0.627)
k
2
×
Far collaboration
−0.802•••
(0.162)
−1.056•••
(0.262)
k
×
Geographic proximity
0.325•••
(0.078)
k
2
×
Geographic proximity
−0.241•••
(0.031)
k
×
Organizational proximity
0.547
(0.679)
k
2
×
Organizational proximity
−0.508•
(0.232)
Close collaboration
3.952•••
(0.628)
3.979•••
(0.618)
3.660•••
(1.148)
2.925••
(1.135)
Far collaboration
0.224•
(0.090)
0.249••
(0.089)
0.244••
(0.089)
−0.359
(0.246)
Geographical proximity
0.041•••
(0.012)
0.041•••
(0.012)
0.045•••
(0.011)
0.053•••
(0.012)
Organizational proximity
0.457•••
(0.118)
0.431•••
(0.119)
0.423•••
(0.116)
0.292
(0.355)
Same class
4.800•••
(0.084)
4.820•••
(0.085)
4.797•••
(0.083)
4.784•••
(0.083)
Activity control
0.503•••
(0.097)
0.515•••
(0.098)
0.469•••
(0.095)
0.481•••
(0.096)
Recent technology
0.268
(0.147)
0.278
(0.144)
0.226
(0.161)
0.245
(0.147)
Backward patent citations
0.022•••
(0.005)
0.021•••
(0.005)
0.020•••
(0.005)
0.021•••
(0.005)
Backward non-patent
citations
0.011
(0.009)
0.014
(0.009)
0.010
(0.008)
0.010
(0.009)
Number of classes
0.184•••
(0.047)
0.209•••
(0.048)
0.204•••
(0.047)
0.201•••
(0.046)
Number of subclasses
−0.030•
(0.013)
−0.016
(0.014)
−0.017
(0.013)
−0.023
(0.013)
Constant
−12.28•••
(0.586)
−12.89•••
(0.657)
−12.21•••
(0.746)
−11.91•••
(0.697)
Log- likelihood
−33,772.4
−33,751.1
−33,738.2
−33720.2
Note:
* 72,801 dyads (52% realized ties versus .0004% in population); •
p
< 0.05; ••
p
< 0.01; •••
p
< 0.001
