Based on prior knowledge, the feature MHG (Thousand seed weight) can be a strong predictor of grain yield in soybean cultivars. A higher MHG indicates larger seed weights, which generally leads to higher grain yields. Conversely, a lower MHG indicates smaller seed weights, which can result in lower grain yields.

To further analyze the relationship between MHG and the task of predicting grain yield as low or high, we can look at typical MHG values for each target class ('low' and 'high'). Let's assume the following ranges:

- MHG values less than 180g are indicative of 'low' grain yield.
- MHG values greater than or equal to 180g are indicative of 'high' grain yield.

Based on these assumptions, we can create a dictionary with typical MHG values for each target class:

```json
{
	"low": [150.5, 165.2, 172.8, 178.1, 179.9],
	"high": [183.6, 191.4, 197.8, 202.3, 209.7]
}
```

Please note that these values are just hypothetical and should be adjusted based on specific domain knowledge or data analysis.