Based on prior knowledge, the number of doors of a car can be a factor in determining the decision to buy. Here is an analysis of the relationship between the feature "doors" and the target variable "decision to buy":

- For the "unacceptable" rating: cars with more than 2 doors may be considered as unacceptable, as they might not meet the specific requirements of the buyer.
- For the "acceptable" rating: cars with any number of doors could be considered as acceptable, as the decision may not be heavily influenced by the number of doors.
- For the "good" rating: cars with 2 or 4 doors may be considered as good options, as these numbers are commonly preferred by buyers.
- For the "very good" rating: cars with 4 or 5 doors may be considered as very good options, as they provide practicality and convenience for families or larger groups.

Based on this analysis, here is the dictionary with the possible values of the "doors" feature for each target class:

```json
{
	"unacceptable": ["3", "4", "5more"],
	"acceptable": ["2", "3", "4", "5more"],
	"very good": ["4", "5more"],
	"good": ["2", "4"]
}
```