Photo: Seeman. Source: Morguefile
Deep learning is a machine-learning method that computers use to recognize complex patterns, like human speech and 3-D objects. It takes a signal – like a sentence – and processes it through multiple layers of calculations and algorithms to come to a conclusion. It’s a way for a computer to “learn” something without being explicitly programmed. Of course, the computer has been programmed, just at a higher, more abstract level.
It uses probability to improve performance. A picture initially looks like it could be either a cat or a lion. But the picture comes from northern Europe, so the algorithm assumes it’s a cat and moves to the next level of evaluation. Deep learning algorithms are trained on a data set, then applied to new data. Remember when you could call Google to look up a phone number? Google used millions of phone calls – with feedback – to train their deep learning voice-recognition algorithm.
Deep learning is the discipline behind self-driving cars, natural language computer assistants like Alexa or Siri, computer-based music recommendations, and even medical diagnoses and drug discoveries. The algorithms use a broad array of correlations and massive databases to generate inferences and decisions, then use the feedback they get to refine their choices.
Deep learning algorithm. Source: Krizhetsky, Sutskiver, & Hinton
There are some things computers are really, really good at. They solve intractable problems that require massive data inputs with amazing speed, like a GPS app finding the fastest route through New York City traffic during rush hour, or directing freight trains across switching systems through Chicago. But there are some simple problems where they seem pathetically incompetent, installing a mandatory update just when I’m about to send out an email. Don’t they know I’m busy?!
It’s like designing a system to breathe underwater. An Aqualung is a complicated marvel of science and engineering. But breathing underwater is trivial … for a fish.
Douglas R. Tengdin, CFA
Charter Trust Company
“The Best Trust Company in New England”