Extreme LOESS values for certain bandwidth

[aubergene]

I'm running a number of series through LOESS and have noticed some give extreme values (far outside the original points) for certain bandwidth values.

I've created a demo here, it exhibits the behaviour for bandwidths of 0.05 and 0.08.

https://observablehq.com/@aubergene/introducing-d3-regression#loess

I'll continue to look at the code but wanted to post in case anyone knew of a solution or was also having issues.

[aubergene]

Possibly related to #16