I really don't like the arrogance coming through the writing style, especially given how clear it is the author has at best basic working knowledge of ML.
Never mind the fact that k-means is ML 101 and the $500M company is likely using more sophisticated ones, the fact that he says the following tells me he's just reading tutorials and plugging data into libraries (which is fine but not with this tone of know-it-all writing):
"I played with the number of clusters, and the one that allowed me to get the most significant clusters was 6 (this was a trial and error approach, for brevity I’ll report just the final outcome)."
Anyone who has studied clustering knows you would at the very least do a scree plot here. You can defer to intuition but there's more to it than running kmeans and claiming you've reverse-engineered a $500M company.
To be fair, he did say that he was just reporting the final outcome. It's unclear exactly what was involved in his trial and error approach or how he judged "significant clusters".
I think this may have something to do with Jeremy Howard's time as president there - I remember watching a few of his tutorials a couple of years ago when he was still at Kaggle and he was really into C#.
I spoke to some Uber drivers in Johannesburg (also insane murder rate) and they said the same thing - things got dangerous when they started having to carry cash.
Worst thing is they were sold on becoming Uber drivers with the promise that it would be less dangerous because it was cashless...
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