Based on my prior knowledge, I can analyze the relationship between the feature "duration" and the target variable "Does this client subscribe to a term deposit?". 

Typically, a longer duration of the last contact might indicate a higher interest from the client, which could lead to a higher probability of subscribing to a term deposit. However, there are no specific thresholds or ranges for the relation between duration and the target variable. 

To provide some insights, I will include 5 typical duration values for each target class: "no" (did not subscribe) and "yes" (subscribed) in the generated dictionary.

```json
{
    "no": [110.0, 190.0, 130.0, 320.0, 280.0],
    "yes": [450.0, 700.0, 550.0, 600.0, 900.0]
}
```

Note: The values provided are just examples and may not accurately reflect the actual data.