Variable Type | Variables | Variable Symbols | Variable Description |
Explained variable | Total factor productivity | tfp | The natural logarithm is taken after calculated by LP |
Explanatory variable | Outward foreign direct investment | ofdi | The year when OFDI exists assigned a value of 1, otherwise assigned a value of 0 |
Mediating variables | Technological innovation | inn | ln (total amount of enterprise R&D investment + 1) |
Exploratory Innovation | eri | ln (amount of expensed R&D investment (expenditure) + 1) | |
Exploitative innovation | eti | ln (amount of capitalized R&D investment (expenditure) + 1) | |
Control variables | Enterprise size | size | ln (net fixed assets + 1) |
Company age | age | ln (current year - year of listing + 1) | |
Debt to asset ratio | lev | Total liabilities/total assets | |
Return on total assets | roa | Net profit/average total assets | |
Growth rate of operating income | growth | Difference between the operating income of the current period and that of the previous year/operating income of previous period | |
Export | export | ln (Enterprise overseas sales revenue + 1) | |
Year | year | Dummy variable of year to control the impact of macro-environmental changes | |
Enterprise | stkcd | Dummy variable of enterprise to control inter-enterprise effects |