Based on my prior knowledge, the feature RIAGENDR represents the respondent's gender. The values 1 and 2 are used to represent male and female respondents, respectively.

To analyze the relationship between the feature RIAGENDR and the target task of predicting age group (senior or non-senior), we can examine the distribution of gender within each age group.

Here is the analysis and the corresponding dictionary:

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

In the above analysis, typical RIAGENDR values for the "Adult" target class representing non-senior individuals are [2.0, 2.0, 1.0, 1.0, 2.0]. Conversely, for the "Senior" target class representing senior individuals, typical RIAGENDR values are [1.0, 1.0, 2.0, 2.0, 1.0].