1Understanding the "Median" in this GraphUnderstanding the "Median" in this Graph

I agree in that this is a somewhat misleading visualisation choice.

The explanation seems to be in the examples at the bottom of `?plot.ga-method`

:

The relevant code for the shaded area (ribbon) is

```
geom_ribbon(aes(x = iter, ymin = median, ymax = max,
colour = "median", fill = "median"))
```

So the "median" ribbon seems to cover fitness values [median, max] on the y-axis.

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