| Variable type | Variable symbol | Variable name | Variable definition |
| dependent variable | Cash1 | Cash holdings | cash/total assets |
| Cash2 | Cash holdings | holdings (cash + short − term investments) /total assets | |
| independent variable | Relationship | CEO-CFO social relations | When the CEO and CFO graduate school or place of birth are the same, Relationship = 1, otherwise Relationship = 0 |
| Control variable | Cf | Operating cash flows | Operating cash flows/total assets |
| Lev | Gearing ratio | Total liabilities/total assets | |
| Size | Company size | ln(Total assets) | |
| Nwc | Net working capital | (current assets-current liabilities-cash) /total assets | |
| Capex | Capital expenditure | [Year t (fixed assets + intangible assets + other non-current assets) − Year t − 1 (fixed assets + intangible assets + other non-current assets)] | |
| Growth | Revenue growth rate | (revenue for Year T-revenue for Year t − 1) /revenue for Year t − 1 | |
|
| dummydiv | Dividends paid | when cash dividends are paid, dummdiv = 1; otherwise, dummdiv = 0. |