Earlier quoted context omitted.
But you don't train the algorithm to make the same decision humans did. You train it to maximize your objective function. I algorithmically trade the stock market. I don't train my model by asking whether it trades the way I would. The whole point is for it to do a better job than me! I train the model to maximize my returns [1] in backtests and simulations - if it trades differently than I do, so much the better! [1…
> But you don't train the algorithm to make the same decision humans did. You train it to maximize your objective function. In the idea case you would, sure. In practice mortgages take 25 years to deliver outcome data and the point isn't necessarily to get better outcomes, the mortgage provider would be content to get exactly the same outcomes (or even slightly worse outcomes) if it let them replace a large number of…
Mortgages are very specifically an area where you do. First of all, there is historical data.
Second of all, you can backtest well before 25 years. A couple of weeks ago I wrote a blog post explaining specifically how to make measurements in the presence of delayed reactions - I'm discussing a situation involving sensor networks, literally the same mathematics would work for mortgage default or refinance: https://www.chrisstucchio.com/blog/2016/delayed_reactions.ht...
Third, mortgage lenders can often backtest alternate decisions because there are pretty straightforward relationships between decisions. Some of them are even mechanistic, e.g. refinance_risk(interest_rate) and default_prob(interest_rate) are monotonically increasing.
You seem to think we are living in the exact specific dark age necessary to make your morality play poignant and relevant. That's about as silly as Star Trek landing on all sorts of alien planets, each one designed to highlight one specific social issue from USA 1966.