| 变量 | (1) | (2) | (3) |
| 低收入 | 中等收入 | 高收入 | |
| 保质期 | 6.650%** | 3.963% | 5.761% |
| (0.028) | (0.029) | (0.035) | |
| 信息关注 | 23.708%*** | 20.531%*** | 34.705%*** |
| (0.035) | (0.034) | (0.033) | |
| 物价波动 | 15.547%*** | 8.092%* | 19.258%*** |
| (0.037) | (0.047) | (0.065) | |
| 采购物资间隔 | 4.826%* | 8.261%** | 4.487% |
| (0.026) | (0.036 ) | (0.040) | |
| 控制变量 | YES | YES | YES |
| 卡方 | 99.08 (p = 0.000) | 83.46 (p = 0.000) | 65.62 (p = 0.000) |
| R2 | 0.412 | 0.5883 | 0.5841 |