Table 6.
Determinants of patent output at the firm level
| Model
|
||||
|---|---|---|---|---|
| 1 | 2 | 3 | 4 | |
| Intercept | 5.159* | 5.292* | 4.252* | 4.037* |
| (1.032) | (1.042) | (0.859) | (0.839) | |
| Percent of coauthorships | 7.340* | 6.897* | 5.137* | 4.493* |
| with universities | (1.611) | (1.680) | (1.789) | (1.759) |
| Papers per research dollar | 0.005 | 0.061* | ||
| (0.006) | (0.026) | |||
| Firm dummies | Yes | Yes | ||
| Time trend | −0.227* | −0.231* | −0.203** | −0.211* |
| (0.045) | (0.045) | (0.038) | (0.037) | |
| RMSE | 0.987 | 0.987 | 0.777 | 0.754 |
| R-squared | 0.293 | 0.301 | 0.611 | 0.638 |
| Intercept | 4.043* | 2.380* | 2.551* | 2.515* |
| (1.358) | (1.198) | (1.146) | (1.118) | |
| Percent of publications by | 2.052 | 3.897* | 3.358* | 3.236* |
| top 10 authors | (1.489) | (1.717) | (1.646) | (1.613) |
| Percent of coauthorships | 4.870* | 4.305* | ||
| with universities | (1.749) | (1.726) | ||
| Papers per research dollar | 0.056* | |||
| (0.002) | ||||
| Firm dummies | Yes | Yes | Yes | |
| Time trend | −0.142* | −0.129* | −0.179* | −0.187* |
| (0.048) | (0.036) | (0.039) | (0.038) | |
| RMSE | 1.093 | 0.792 | 0.757 | 0.738 |
| R-squared | 0.132 | 0.595 | 0.635 | 0.658 |
Ordinary least-squares regression. Dependent variable: Important patents per research dollar. 1980–1988 data, 84 observations. Standard errors are in parentheses. RMSE, root mean squared error.
*
, Significant at 5% level.
**
, Significant at 10% level.