```json
{
	"low": [6.2, 6.5, 5.9, 5.8, 6.1],
	"high": [8.7, 9.1, 8.4, 8.9, 9.2]
}
```
Based on prior knowledge, it is observed that cultivars with a low grain yield tend to have a narrower range of values for the NS feature, typically falling between 5.8 and 6.5. On the other hand, cultivars with a high grain yield tend to have a broader range of values for the NS feature, typically falling between 8.4 and 9.2. The dictionary provides 5 typical NS values for each target class - low and high.