Through prior knowledge, we can assume that the age group for 'Senior' is typically 65 years and above. Therefore, based on this assumption, we can analyze the relationship between the feature 'RIAGENDR' (Respondent's Gender) and the target variable 'age group' (Senior or non-senior).

To create the dictionary, we will need to identify typical RIAGENDR values for both the 'Adult' and 'Senior' target classes.

```json
{
	"Adult": [1.0, 2.0, 1.0, 2.0, 1.0],
	"Senior": [1.0, 2.0, 1.0, 2.0, 1.0]
}
```

Please note that the values in the lists are float representations of the gender values.