Labor Union Effects on Innovation and Commercialization Productivity: An Integrated Propensity Score Matching and Two-Stage Data Envelopment Analysis
Abstract
:1. Introduction
2. Literature Review
2.1. Two-Stage DEA Model for Analyzing Innovation and Commercialization Productivity
2.2. Propensity Score Matching (PSM) Methodology
2.3. Labor Unions and Firm R&D
3. Model and Data Sources
3.1. Model
3.2. Data
Variable | Description | Unit of Measurement | Variable Used in the Analysis | Previous Studies |
---|---|---|---|---|
Inputs | Internal R&D expenditure | Korean won (million) | Average of 2007–2009 | [25,70,71] |
External R&D expenditure | ||||
R&D employees | Number | |||
Intermediates | Process innovation patent applications | Number | Sum of 2007–2009 | [25,70,71] |
Product innovation patent applications | ||||
Outputs | Sales | Korean won (million) | 2009 | [71] |
Operating income | ||||
Labor union | Unionized, non-unionized | Nominal scale | 2009 | [57,72] |
Variable | Description | Unit of Measurement | Previous Studies |
---|---|---|---|
Educational level | Ratio of highly educated employees (Master’s degree or higher employees/total employees) | Percentage | [80,81,82,83,84] |
Industry | High-tech or low-tech | Nominal scale | [82,81,82,83,84] |
Firm size | Big, medium, and small | Ordinal scale | [80,81,82,83,84] |
Firm age | Present year—established year | Number | [84,85,86] |
Company location | Urban or rural | Nominal scale | [82,83,84] |
Background Variables | Coeff. | p-Value |
---|---|---|
Educational level | −0.0004265 | 0.954 |
Industry | −0.1110335 | 0.282 |
Firm size 1 (large) | 2.033772 | 0.000 *** |
Firm size 2 (medium) | 1.210334 | 0.000 *** |
Firm age | 0.0278171 | 0.000 *** |
Firm location | −0.1073023 | 0.306 |
Constant | −2.262771 | 0.000 *** |
Number of observations | 997 | |
Pseudo R2 | 0.3239 |
Variable | Unmatched | Mean | %Bias | %Reduct |bias| | t-Test | ||
---|---|---|---|---|---|---|---|
Matched | Treated | Control | t | p > |t| | |||
Industry | U | 0.51119 | 0.52538 | −2.8 | −0.40 | 0.691 | |
M | 0.51119 | 0.46269 | 9.7 | −242.0 | 1.12 | 0.262 | |
Firm location | U | 0.46269 | 0.47051 | −1.6 | −0.22 | 0.827 | |
M | 0.46269 | 0.45522 | 1.5 | 4.6 | 0.17 | 0.863 | |
Big | U | 0.49254 | 0.07682 | 103.6 | 16.85 | 0.000 | |
M | 0.49254 | 0.48881 | 0.9 | 99.1 | 0.09 | 0.931 | |
Medium | U | 0.47761 | 0.42798 | 10.0 | 1.40 | 0.162 | |
M | 0.47761 | 0.48134 | −0.7 | 92.5 | −0.09 | 0.931 | |
Small | U | 0.02985 | 0.4952 | −124.5 | −14.91 | 0.000 | |
M | 0.02985 | 0.02985 | 0.0 | 100.0 | −0.00 | 1.000 | |
Education level | U | 4.3947 | 4.8502 | −5.8 | −0.81 | 0.420 | |
M | 4.3947 | 4.1276 | 3.4 | 41.4 | 0.46 | 0.643 | |
Firm age | U | 30.862 | 15.804 | 111.7 | 17.47 | 0.000 | |
M | 30.862 | 30.851 | 0.1 | 99.9 | 0.01 | 0.994 |
Frequency | Percent | Cumulative Percent | |
---|---|---|---|
1 | 81 | 61.36 | 61.36 |
2 | 29 | 21.97 | 83.33 |
3 | 9 | 6.82 | 90.15 |
4 | 1 | 0.76 | 90.91 |
5 | 1 | 0.76 | 91.67 |
6 | 3 | 2.27 | 93.94 |
7 | 2 | 1.52 | 95.45 |
8 | 1 | 0.76 | 96.21 |
9 | 2 | 1.52 | 97.73 |
10 | 1 | 0.76 | 98.48 |
11 | 1 | 0.76 | 99.24 |
12 | 0 | 0 | 99.24 |
13 | 0 | 0 | 99.24 |
14 | 1 | 0.76 | 100.00 |
Total | 132 | 100.00 |
N = 400 | Min. | Max. | Mean | Std. Dev. |
---|---|---|---|---|
Internal R&D investment | 2 | 860,769 | 12,240.43 | 59,256.52 |
External R&D investment | 0 | 198,639 | 1560.24 | 10,552.71 |
R&D employees | 0 | 1233 | 42.16 | 98.03 |
Product innovation patent applications | 0 | 920 | 9.70 | 71.50 |
Process innovation patent applications | 0 | 4723 | 44.07 | 286.55 |
Sales | 710 | 15,759,742 | 388,407.62 | 1,225,270.89 |
Operating income | −293,400 | 2,233,174 | 26,352.59 | 136,248.27 |
4. Empirical Results
4.1. Productivity Analysis
N = 400 | Innovation Efficiency Score | Commercialization Efficiency Score |
---|---|---|
Mean | 0.2087 | 0.4484 |
Std. Dev. | 0.28273 | 0.10058 |
Min. | 0.00 | 0.07 |
Max. | 1.00 | 1.00 |
Total N = 400 | N | Mean Rank | |
---|---|---|---|
Rank of commercialization productivity (1) – Rank of innovation productivity (2) | (1) − (2) < 0 | 212 | 194.01 |
(1) − (2) > 0 | 188 | 207.81 | |
(1) − (2) = 0 | 3 | - |
4.2. Comparative Analysis
Total N = 400 | Labor Union | N | Mean Rank | Sum of Rank |
---|---|---|---|---|
Innovation stage | Unionized | 268 | 207.12 | 55509.00 |
Non-unionized | 132 | 187.05 | 24691.00 | |
Commercialization stage | Unionized | 268 | 193.78 | 51932.00 |
Non-unionized | 132 | 214.15 | 28268.00 |
5. Conclusions
5.1. Summary
5.2. Implications and Limitations
Author Contributions
Conflicts of Interest
References
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Chun, D.; Chung, Y.; Woo, C.; Seo, H.; Ko, H. Labor Union Effects on Innovation and Commercialization Productivity: An Integrated Propensity Score Matching and Two-Stage Data Envelopment Analysis. Sustainability 2015, 7, 5120-5138. https://doi.org/10.3390/su7055120
Chun D, Chung Y, Woo C, Seo H, Ko H. Labor Union Effects on Innovation and Commercialization Productivity: An Integrated Propensity Score Matching and Two-Stage Data Envelopment Analysis. Sustainability. 2015; 7(5):5120-5138. https://doi.org/10.3390/su7055120
Chicago/Turabian StyleChun, Dongphil, Yanghon Chung, Chungwon Woo, Hangyeol Seo, and Hyesoo Ko. 2015. "Labor Union Effects on Innovation and Commercialization Productivity: An Integrated Propensity Score Matching and Two-Stage Data Envelopment Analysis" Sustainability 7, no. 5: 5120-5138. https://doi.org/10.3390/su7055120