| Variable | Mean | Std. Dev. | Description |
|---|---|---|---|
| Disposable bag | 0.38 | 0.48 | 1 if customer used a plastic bag, 0 otherwise (dependent variable) |
| Token | 0.85 | 0.36 | 1 if after implementation of token program, 0 otherwise |
| StoreA | 0.70 | 0.46 | 1 if observation comes from the store A (treated convenience store), 0 otherwise |
| Total items | 2.09 | 1.44 | Total number of items purchased per transaction |
| Small items | 1.29 | 1.19 | Number of small items purchased per transaction (can of soda or smaller) |
| Medium items | 0.63 | 0.97 | Number of medium items purchased per transaction (any items in between small and large) |
| Large items | 0.17 | 0.50 | Number of large items purchased per transaction (2 liters of soda, half- gallon of milk, 6-packs of bottled water) |
| Evening | 0.62 | 0.49 | 1 if purchase occurred in evening (after 5 p.m.), 0 otherwise |
| Weekday | 0.93 | 0.26 | 1 if the purchase occurred Monday through Friday, 0 otherwise |
| Preceding customer | 0.38 | 0.48 | 1 if the previous customer used a plastic bag, 0 otherwise |
| Female | 0.49 | 0.52 | Gender of the customer: 1 if female, 0 otherwise |
| Percentage of plastic bag use | 0.44 | 0.13 | Percentage of the customer using plastic bags for each day before intervention |
| Trend | 4.5 | 2.36 | Trend representing each day before the intervention of token program (since we had 8 control days, trend represented as 1, 2…,8) |