Based on prior knowledge, Oldpeak is a numeric variable measured in depression and is often used as an indicator for heart disease. Lower values of Oldpeak generally indicate a lower likelihood of heart disease, while higher values indicate a higher likelihood.

To analyze the relationship between Oldpeak and the presence of heart disease, we can examine the typical Oldpeak values for each target class ('no' and 'yes').

Here is a dictionary summarizing the relationship between Oldpeak and the target variable:

```json
{
	"no": [0.0, 0.5, 1.0, 1.5, 2.0],
	"yes": [2.5, 3.0, 3.5, 4.0, 4.5]
}
```

This dictionary shows the typical Oldpeak values for each target class. For the 'no' class (indicating no heart disease), common Oldpeak values range from 0.0 to 2.0, while for the 'yes' class (indicating heart disease), common Oldpeak values range from 2.5 to 4.5.

Please note that these values are just examples and may vary depending on the specific dataset used for analysis.