| Variable type | Variable name | Variable symbol | Variable measure method |
| Explained variable | Operating cash flow return on total assets | CFR | Operating cash flow/total assets |
| Explanatory variable | Political connection index of chairman | PCIndex_Chair | Obtaining political l connection index of chairman and CEO by using analytic hierarchy process (ahp). |
| Political connection index of CEO | PCIndex_CEO | ||
| Whether the company is private-owned | Private | If the company is private-owned, recorded as 1, otherwise to 0. | |
| Control variable | Company size | LnAsset | Natural logarithm of total assets |
| Leverage ratio | Leverage | Total debt/total assets | |
| Book-to-Market ratio | BM | It is the reciprocal of the price/book value ratio | |
| Tobin’s q | TQ | Enterprise value/asset replacement cost |