Based on prior knowledge, we can analyze the relationship between the feature "poutcome" and the task of whether the client subscribes to a term deposit.

Analysis:
- The feature "poutcome" represents the outcome of the previous marketing campaign.
- It is a categorical variable with the following categories: ['unknown', 'failure', 'other', 'success'].
- It is likely that clients who had a successful outcome in the previous campaign (poutcome='success') are more likely to subscribe to a term deposit.
- On the other hand, clients who had a failure outcome (poutcome='failure') in the previous campaign may be less inclined to subscribe to a term deposit.
- It is difficult to predict the impact of 'unknown' and 'other' outcomes on the likelihood of subscribing to a term deposit. Therefore, it is not necessary to include these categories in the dictionary.

Based on this analysis, the dictionary can be generated as follows:

```json
{
    "no": ["failure"],
    "yes": ["success"]
}
```

Note: The list of values for each target class may vary depending on the dataset.