To analyze the relationship between the feature BMXBMI and the target variable age group (Senior or non-senior), we need to determine the appropriate ranges of BMI values for each age group. 

BMI is calculated using a person's weight in kilograms divided by the square of their height in meters. Generally, BMI values are categorized into different ranges to assess weight status. For this analysis, we will consider the following ranges:

- Underweight: BMI < 18.5
- Normal weight: 18.5 ≤ BMI < 25
- Overweight: 25 ≤ BMI < 30
- Obesity class I: 30 ≤ BMI < 35
- Obesity class II: 35 ≤ BMI < 40
- Obesity class III: BMI ≥ 40

Based on prior knowledge and commonly used BMI classifications, we can assume that higher BMI values are more likely to be associated with older age groups. Therefore, we expect to see higher BMXBMI values in the "Senior" age group compared to the "Adult" age group.

Here is the dictionary containing typical BMXBMI values for each age group:

```json
{
	"Adult": [20.5, 23.8, 24.6, 26.2, 27.9],
	"Senior": [24.8, 26.7, 28.3, 30.1, 31.9]
}
```

Please note that the provided values are just examples, and the actual range of BMXBMI values for each age group may vary depending on the dataset and population being analyzed.