| Name | Symbols | Definition |
Explained variable | intensity of R&D expenditure | rdintensity | R&D expenditure ÷ total assets |
Explanatory variable | financial subsidy | subsidy | capital subsidy ÷ total assets |
enterprise lifecyle | lifecycle | The enterprise lifecycle is divided by the combination of cash flow indicators. | |
Control variables | duration of the enterprise | age | Business registration date from the current time |
enterprise size | size | log of total assets | |
output | roa | net profit ÷ total assets | |
per capita capital | lk | Retained earnings ÷ total staff | |
net profit | profit | log of absolute net profit | |
growth | growth | (current year revenue − last year revenue) ÷ last year revenue | |
profitability | EPS | earnings per share |