Click on image to see the presentation from The Kepler Conference for Astrological Research, Jan 2017.
[Edit: a crazy further reduction in RMSE was achieved by finally using a neural net. The quick write-up of that can be seen here.
A full journal article was just approved for publication (March 2018). It will be referenced in the bibliography.]
To hear the audio of the misspellings, download the original file below and mouse over on the second red graph.