Analyzing the relationship between the feature RIDAGEYR and the task of predicting the age group, "Senior" or "Non-Senior", the following assumptions can be made based on prior knowledge:

1. The age group for adults typically ranges from 18 to 65 years.
2. The age group for seniors typically ranges from 65 and above.

Based on these assumptions, the dictionary can be created as follows:

```json
{
	"Adult": [18.0, 30.0, 45.0, 55.0, 62.0],
	"Senior": [66.0, 70.0, 75.0, 80.0, 90.0]
}
```

Please note that the values provided are approximations and may vary depending on the specific context and dataset being analyzed.