Andy Mueller (NYU) started the day with an introduction to machine learning and the scikit-learn package (of which he is a developer). His tutorial was beautiful, as it followed a fully interactive and operational Jupiter notebook. There was an audible gasp in the room when the astronomers saw the magic of dimensionality reduction in the form of the t-SNE algorithm. It is truly magic! There was much debate in the room about whether it was useful for anything other than blowing your mind (ie, visualization).
In the afternoon, Baron and I refactored our galaxy projection/deprojection code in preparation for inferring the galaxy itself. This refactor was non-trivial (and we learned a lot about the Jupyter notebook!), but it was done by the end of the day. We discussed next steps for the galaxy inference, which we hope to start tomorrow!