﻿WEBVTT

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<v ->Hi, I'm Hilary Mason. I'm a computer scientist.</v>

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And today, I've been asked to explain machine learning

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in five levels of increasing complexity.

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Machine learning gives us the ability to learn things

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about the world from large amounts of data

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that we as human beings can't possibly study or appreciate.

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So machine learning is when we teach computers

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to learn patterns from looking at examples in data,

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such that they can recognize those patterns

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and apply them to new things that they haven't seen before.

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[playful music]

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Hi.

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<v ->Hi.</v>

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<v ->I'm Hilary, what's your name?</v>

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<v ->I'm Brynn.</v>

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<v ->Do you know what machine learning means?</v>

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Have you heard that before?

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<v ->No.</v>

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<v ->So machine learning is a way that we teach computers</v>

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to learn things about the world by looking at patterns

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and looking at examples of things.

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So can I show you an example

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of how a machine might learn something?

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<v ->Sure.</v>

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<v Hilary>So is this a dog or a cat?</v>

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<v ->It's a dog.</v>

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<v ->And this one?</v>

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<v ->A cat.</v>

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<v ->And what makes a dog, a dog and a cat, a cat?</v>

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<v ->Well, dogs are very playful, I think, more than cats.</v>

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Cats lick themselves more than dogs, I think.

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<v ->That's true.</v>

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Do you think, if we look at these pictures,

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do you think maybe we could say,

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"Well, they both have pointy ears,

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but the dogs have a different kind of body

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and the cats like to stand up a little different."?

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Do you think that makes sense?

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<v ->Yeah.</v>
<v ->Yeah.</v>

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What about this one?

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<v ->A dog.</v>

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A cat.

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I think, a cat?

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Because it's more skinny.

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And also, its legs are like really tall

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and its ears are a little pointy.

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<v ->This one's a jackal. And it's actually a kind of dog.</v>

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But you made a good guess.

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That's what machines do too. They make guesses.

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Is this a cat or a dog?

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<v Brynn>None.</v>

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<v Hilary>None. What is it?</v>

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<v ->It's humans.</v>

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<v ->And how did you know that it's not a cat or a dog?</v>

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<v ->Because cats and dogs...</v>

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Because they walk on their paws

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and their ears are like right here, not right here,

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and they don't wear watches.

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<v ->And so, you did something pretty amazing there.</v>

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Because we asked the question, "Is it a cat or a dog?"

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And you said, "I disagree with your question. It's a human."

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So machine learning is when we teach machines

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to make guesses about what things are

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based on looking at a lot of different examples.

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And I build products that use machine learning

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to learn about the world and make guesses

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about things in the world.

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When we try to teach machines to recognize things

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like cats and dogs, it takes a lot of examples.

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We have to show them tens of thousands

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or even millions of examples

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before they can get even close to as good at it as you are.

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Do you have tests in school?

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<v ->Yeah, I have.</v>

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After every unit, we have a review and then we have a test.

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<v ->Are those like the practice problems</v>

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you do before the test?

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<v ->Well, just like everything that's gonna be on the test</v>

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is on the review.

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<v ->Which means that in the test,</v>

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you're not seeing any problems

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that you don't know how to solve.

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As long as you did all your practice, right?

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<v ->Yeah.</v>

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<v ->So machines work the same way.</v>

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If you show them a lot of examples and give them practice,

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they'll learn how to guess.

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And then when you give them the test,

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they should be able to do that.

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So we looked at eight pictures

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and you were able to answer really quickly.

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But what would you do if I gave you 10 million examples?

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Would you be able to do that so quickly?

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<v ->No.</v>

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<v ->So one of the differences between people and machines</v>

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is that people might be a little better at this,

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but can't look at 10 million different things.

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So now that we've been talking about machine learning,

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is this something you want to learn how to do?

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<v ->Kind of.</v>

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Because I kind of want to become a spy.

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And we used to do coding,

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so I may be kind of good at it.

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<v ->And machine learning is a great way to use</v>

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all those math skills, all those coding skills,

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and would be a super cool tool for a spy.

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[quirky music]

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<v ->Hello.</v>

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<v ->Hi. Are you a student, Lucy?</v>

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<v ->Yes, I just finished ninth grade.</v>

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<v ->Congratulations.</v>

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<v ->Thank you. It's very exciting.</v>

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<v ->Have you ever heard of machine learning before?</v>

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<v ->I'm going to assume that it means humans being able</v>

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to teach machines or robots how to learn themselves?

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<v ->That's right.</v>

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When we teach machines to learn from data,

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to build a model from that data or a representation of that,

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and then to make a prediction.

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One of the places we often find machine learning

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in the real world is in things like recommendation systems.

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So do you have an artist that you really like?

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<v ->Yeah, Melanie Martinez.</v>

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<v ->So I'm gonna look up Melanie Martinez.</v>

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And it says here, "If you like Melanie Martinez,

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one of the other songs you might like is by Au/Ra."

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Do you know who that is?

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<v ->I do not.</v>

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So let's listen to a hint of this song.

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<v ->Okay.</v>

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[alternative pop music]

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<v ->All right.</v>

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So why do you think Spotify might've recommended that song?

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<v ->Well, I know that in Melanie Martinez's music,</v>

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she used a lot of the filtered voice

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to make it sound very deep and low

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and that song had that.

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<v ->And that's actually a really interesting thing</v>

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to think about because that creepy vibe

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is something that you can perceive and I can perceive,

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but it's actually really hard to describe to a machine.

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What do you think might go into that?

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<v ->Pitch of the music.</v>

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If it's really low or if it's super high,

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it could know that.

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What can the machine understand?

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<v ->It's a great question.</v>

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The machine can understand

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whatever we tell it to understand.

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So there might be a person thinking about things,

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like the pitch or the pacing or the tone,

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or sometimes machines can figure out

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things about music or images or videos

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that we don't tell it to discover,

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but that it can learn

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from looking at a lot of different examples.

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Why do you think companies might use machine learning?

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<v ->Well, I think things like Facebook or Instagram,</v>

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they probably use it to target ads.

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<v ->Sometimes, the ads you see are really uncanny.</v>

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And I think that's because they're based on so much data.

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They know where you live. They know where your device is.

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It's also important to realize that people in aggregate

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are actually pretty predictable.

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Like when we talk to each other,

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we like to talk about the novel things,

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like here, we're having this conversation.

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We don't do this every day.

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But we probably still eat breakfast.

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We're gonna eat lunch. We're gonna eat dinner.

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You probably are going to the same home

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you go to most of the time.

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And so, they're able to take that data

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that we already give them and make predictions based on that

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as to what ads they should show us.

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<v ->So, you're saying I give them enough data as it is</v>

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about what I might be talking about or thinking about

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that they can read my mind,

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[Hilary laughs]

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but just use the data that I've already given them.

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And it almost seems like

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they're watching us.
<v ->That's right.</v>

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To do machine learning, we use something called algorithms.

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Have you heard of algorithms before?

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<v ->A set of steps or a process</v>

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carried out to complete something?

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<v ->That's right.</v>

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<v ->So do you think that we've been able</v>

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to teach machines enough

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so that they can do things that even we can't do?

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And on the opposite side of that,

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do you think there are things that we can do

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that a machine might never be able to do?

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<v ->So there are things that machines are really great at</v>

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that humans are actually not great at.

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And imagine watching every video posted to TikTok every day.

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So we just don't have enough time to do that

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at the rate at which we can actually watch those videos.

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But a machine can analyze all of them

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and then make recommendations to us.

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And then thinking about things that machines are bad at

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and people are good at, people are really great

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with only one or two examples of learning something new

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and incorporating that into our model of the world

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to make good decisions.

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Whereas machines often need tens of thousands of examples,

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and that's not even getting into things like good judgment

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because we care about people,

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because we can imagine a future that we want to live in

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that doesn't exist today.

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And that's something that is still uniquely human.

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Machines are great at predicting

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based on what they've seen in the past,

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but they're not creative.

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They're not going to invent.

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They're not gonna, you know,

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really change where we're gonna go.

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That's up to us.

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[serene music]

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<v ->I'm Sunny.</v>

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<v Hilary>And what are you majoring in?</v>

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<v ->I study Math and Computer Science.</v>

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<v ->So in your studies,</v>

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have you learned about machine learning?

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<v ->Yeah, I have.</v>

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So to me, machine learning is essentially

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exactly what it sounds like.

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It's trying to teach a machine specifics about something

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by inputting a lot of data points

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and slowly, the machine will build up knowledge

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about it over time.

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For example, my Gmail program,

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I assume that there would be a lot of, like,

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machine learning models happening at once, right?

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<v ->Absolutely.</v>

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And that's a great example because you have models

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that are operating to do things like figure out

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if a new email is spam or not.

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So what would you think

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about if you were looking at an email

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and trying to decide if it went in one category or another?

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<v ->I'd probably look at certain keywords.</v>

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Maybe if the recipient and the sender

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had exchanged emails before

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and generally, those fell into in the past.

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<v ->So these are things we would call features.</v>

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And we go through a process where we do feature engineering,

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where somebody looks at the example and says,

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"Okay, these are the things that I think might allow us

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to statistically tell the difference

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from something in one category versus another.

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So for example, perhaps you don't speak Russian,

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you start getting a lot of email in Russian.

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<v ->Obviously, like the features that you just described</v>

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are features which a person would have had to think about.

256
00:10:18.210 --> 00:10:19.043
Are there features

257
00:10:19.043 --> 00:10:21.830
which, like, the machine itself could learn?

258
00:10:21.830 --> 00:10:23.570
<v ->This is a great question</v>

259
00:10:23.570 --> 00:10:26.210
because it really gets to the difference

260
00:10:26.210 --> 00:10:28.840
between some of our different tools

261
00:10:28.840 --> 00:10:30.420
in our machine learning tool belt

262
00:10:30.420 --> 00:10:32.520
in addressing problems like this.

263
00:10:32.520 --> 00:10:37.170
So if we were to use a supervised learning classic

264
00:10:37.170 --> 00:10:38.800
classification approach,

265
00:10:38.800 --> 00:10:41.650
a person would need to think about those features

266
00:10:41.650 --> 00:10:43.930
and creatively come up with them

267
00:10:43.930 --> 00:10:46.030
in approach we call the kitchen sink approach,

268
00:10:46.030 --> 00:10:48.450
which is just try everything you can possibly think of

269
00:10:48.450 --> 00:10:49.560
and see what works.

270
00:10:49.560 --> 00:10:53.040
Unsupervised learning, where we don't have labeled data

271
00:10:53.040 --> 00:10:57.290
and we're trying to infer some structure out of the data

272
00:10:57.290 --> 00:10:59.840
is you're projecting that data into a space

273
00:10:59.840 --> 00:11:02.120
and looking for things like clusters.

274
00:11:02.120 --> 00:11:03.800
And there's a bunch of really fun math

275
00:11:03.800 --> 00:11:07.060
about how you do that, how you think about distance

276
00:11:07.060 --> 00:11:11.290
and by distance, I mean that if we have two data points

277
00:11:11.290 --> 00:11:14.670
in space, how do we decide if they're similar or not?

278
00:11:14.670 --> 00:11:19.320
<v ->And how do the algorithms themselves usually differ</v>

279
00:11:19.320 --> 00:11:22.050
between unsupervised and supervised learning.

280
00:11:22.050 --> 00:11:24.500
<v ->Supervised learning, we have our labels</v>

281
00:11:24.500 --> 00:11:28.010
and we're trying to figure out what statistically indicates

282
00:11:28.010 --> 00:11:31.790
if something matches one label or another label.

283
00:11:31.790 --> 00:11:32.960
Unsupervised learning,

284
00:11:32.960 --> 00:11:35.330
we don't necessarily have those labels.

285
00:11:35.330 --> 00:11:37.250
That's the thing we're trying to discover.

286
00:11:37.250 --> 00:11:39.730
So reinforcement learning is another technique

287
00:11:39.730 --> 00:11:41.170
that we use sometimes.

288
00:11:41.170 --> 00:11:43.290
You can think about it like a turn in a game

289
00:11:43.290 --> 00:11:47.300
and you can play, you know, millions and millions of trials

290
00:11:47.300 --> 00:11:49.520
so that you're able to develop a system

291
00:11:49.520 --> 00:11:52.310
that by experimenting with reinforcement learning

292
00:11:52.310 --> 00:11:54.440
can eventually learn to play these games

293
00:11:54.440 --> 00:11:55.970
pretty successfully.

294
00:11:55.970 --> 00:11:59.810
Deep learning, which is essentially using neural networks

295
00:11:59.810 --> 00:12:03.630
and very large amounts of data to eventually iterate

296
00:12:03.630 --> 00:12:06.400
on a network structure that can make predictions.

297
00:12:06.400 --> 00:12:09.603
<v ->With reinforcement learning versus deep learning,</v>

298
00:12:10.440 --> 00:12:13.730
it seems to me that reinforcement learning,

299
00:12:13.730 --> 00:12:15.600
is it sort of like the kitchen sink approach

300
00:12:15.600 --> 00:12:17.100
that you were talking about earlier,

301
00:12:17.100 --> 00:12:19.690
where you're just kind of trying everything?

302
00:12:19.690 --> 00:12:23.070
<v ->It is, but it also thrives in environments</v>

303
00:12:23.070 --> 00:12:25.870
where you have a decision point,

304
00:12:25.870 --> 00:12:28.220
a pallet of actions to choose from.

305
00:12:28.220 --> 00:12:30.670
And it actually comes historically

306
00:12:30.670 --> 00:12:33.680
from trying to train a robot to navigate a room.

307
00:12:33.680 --> 00:12:36.720
If it bonks into this chair, it can't go forward anymore.

308
00:12:36.720 --> 00:12:38.410
And if it falls into that pit,

309
00:12:38.410 --> 00:12:40.640
you know, it's not going to succeed.

310
00:12:40.640 --> 00:12:44.460
But if it keeps exploring, it'll eventually get to the goal.

311
00:12:44.460 --> 00:12:45.480
<v ->Oh, like roombas?</v>

312
00:12:45.480 --> 00:12:46.398
<v Hilary>Yes.</v>

313
00:12:46.398 --> 00:12:47.324
[both laugh]

314
00:12:47.324 --> 00:12:49.750
<v ->Oh, I didn't realize it was that deep, almost.</v>

315
00:12:49.750 --> 00:12:51.830
Is there a situation which you'd want to use

316
00:12:51.830 --> 00:12:52.970
a deep learning algorithm

317
00:12:52.970 --> 00:12:55.500
over a reinforcement learning algorithm?

318
00:12:55.500 --> 00:12:57.800
<v ->So typically, you would choose deep learning</v>

319
00:12:57.800 --> 00:13:00.990
if you have sufficient high quality data,

320
00:13:00.990 --> 00:13:03.740
hopefully labeled in a useful way.

321
00:13:03.740 --> 00:13:08.740
If you really are happy not to necessarily understand

322
00:13:09.210 --> 00:13:11.940
or be able to interpret what your system is doing

323
00:13:11.940 --> 00:13:13.380
or you're willing to invest

324
00:13:13.380 --> 00:13:16.920
in another set of work afterwards to understand

325
00:13:16.920 --> 00:13:19.450
what the system is doing once you've already trained it.

326
00:13:19.450 --> 00:13:22.320
And this also comes down to the fact that some things

327
00:13:22.320 --> 00:13:25.650
are actually really easy to solve with linear regression

328
00:13:25.650 --> 00:13:27.890
or simple statistical approaches.

329
00:13:27.890 --> 00:13:29.396
And some things are impossible.

330
00:13:29.396 --> 00:13:31.760
<v ->What would be the outcome if you were to choose</v>

331
00:13:31.760 --> 00:13:33.760
the, quote-unquote, "wrong" approach?

332
00:13:33.760 --> 00:13:36.730
<v ->You build a system that could actually be useless.</v>

333
00:13:36.730 --> 00:13:40.470
So years ago, I had a client that was a big telecom company

334
00:13:40.470 --> 00:13:42.470
and they had a data scientist

335
00:13:42.470 --> 00:13:45.590
who built a deep learning system to predict customer churn.

336
00:13:45.590 --> 00:13:48.600
It actually was very accurate, but it wasn't useful

337
00:13:48.600 --> 00:13:52.210
because nobody knew why the prediction was what it was.

338
00:13:52.210 --> 00:13:53.707
So they could say, you know,

339
00:13:53.707 --> 00:13:55.820
"Sunny, you're likely to quit next month."

340
00:13:55.820 --> 00:13:58.420
But they had no idea what to do about it.

341
00:13:58.420 --> 00:14:01.040
And so, I think there are a bunch of failure modes.

342
00:14:01.040 --> 00:14:03.310
<v ->Would that be an example of, like, linear regression</v>

343
00:14:03.310 --> 00:14:05.780
where the regression is accurate, but,

344
00:14:05.780 --> 00:14:08.040
you know, for marketing purposes, it's like,

345
00:14:08.040 --> 00:14:09.780
if you don't know why I'm quitting the service,

346
00:14:09.780 --> 00:14:11.660
then how can we fix this?

347
00:14:11.660 --> 00:14:12.493
<v ->Yeah.</v>

348
00:14:12.493 --> 00:14:15.680
This is actually a good example of a very real world

349
00:14:15.680 --> 00:14:19.840
kind of machine learning problem where the solution to this

350
00:14:19.840 --> 00:14:21.920
was to build an interpretable system

351
00:14:21.920 --> 00:14:24.960
on top of the accurate predictions not to throw it away,

352
00:14:24.960 --> 00:14:27.410
but to do a bunch more work to figure out the why.

353
00:14:27.410 --> 00:14:30.770
<v ->How can we improve machine learning algorithms?</v>

354
00:14:30.770 --> 00:14:33.760
<v ->It's actually fairly new</v>

355
00:14:33.760 --> 00:14:36.300
that we're able to solve all of these problems

356
00:14:36.300 --> 00:14:39.410
and start to build these products and apply it in businesses

357
00:14:39.410 --> 00:14:41.870
and apply it, you know, everywhere.

358
00:14:41.870 --> 00:14:44.970
And so, we're still developing good practices

359
00:14:44.970 --> 00:14:48.790
and what it means to be a professional in machine learning.

360
00:14:48.790 --> 00:14:51.782
We're really developing a notion of what good looks like.

361
00:14:51.782 --> 00:14:55.110 line:15% 
[quirky music]

362
00:14:55.110 --> 00:14:59.490 line:15% 
<v ->I'm in my first year of a PhD in Computer Science</v>

363
00:14:59.490 --> 00:15:02.170
and I'm studying natural language processing

364
00:15:02.170 --> 00:15:03.100
and machine learning.

365
00:15:03.100 --> 00:15:04.700
<v ->So would you mind telling me a bit about</v>

366
00:15:04.700 --> 00:15:07.090
what you've been working on or interested in lately?

367
00:15:07.090 --> 00:15:10.000
<v ->I've been looking at understanding persuasion</v>

368
00:15:10.000 --> 00:15:15.000
in online text and the ways that we might be able to

369
00:15:15.030 --> 00:15:18.500
automatically detect the intent behind that persuasion

370
00:15:18.500 --> 00:15:20.040
or who it's targeted at

371
00:15:20.040 --> 00:15:22.670
and what makes effective persuasive techniques.

372
00:15:22.670 --> 00:15:25.060
<v ->So what are some of the techniques you're applying</v>

373
00:15:25.060 --> 00:15:26.850
to look at that debate data?

374
00:15:26.850 --> 00:15:28.740
<v ->Something I'm interested in exploring</v>

375
00:15:28.740 --> 00:15:32.920
is how well it works to use deep learning

376
00:15:32.920 --> 00:15:36.150
and sort of automatically extracted features from this text

377
00:15:36.150 --> 00:15:38.800
versus using some of the more traditional techniques

378
00:15:38.800 --> 00:15:41.300
that we have, things like lexicons

379
00:15:41.300 --> 00:15:43.580
or some sort of template matching techniques

380
00:15:43.580 --> 00:15:46.470
for extracting features from texts.

381
00:15:46.470 --> 00:15:48.650
That's a question I'm just interested in, in general.

382
00:15:48.650 --> 00:15:50.140
When do we really need deep learning

383
00:15:50.140 --> 00:15:52.100
versus when can we use something

384
00:15:52.100 --> 00:15:53.620
that's a little bit more interpretable,

385
00:15:53.620 --> 00:15:55.150
something that's been around for a while?

386
00:15:55.150 --> 00:15:58.000
<v ->Do you think there are going to be general principles</v>

387
00:15:58.000 --> 00:15:59.500
that guide those decisions?

388
00:15:59.500 --> 00:16:01.440
Because right now, it's generally

389
00:16:01.440 --> 00:16:04.280
up to the machine learning engineer to decide

390
00:16:04.280 --> 00:16:05.980
what tools they want to apply.

391
00:16:05.980 --> 00:16:08.270
<v ->I definitely think there is,</v>

392
00:16:08.270 --> 00:16:11.570
but I also, sort of, see it varying a lot

393
00:16:11.570 --> 00:16:12.780
based on the use case,

394
00:16:12.780 --> 00:16:15.520
something that, kind of, works out of the box

395
00:16:15.520 --> 00:16:17.770
and maybe works a little bit more automatically

396
00:16:17.770 --> 00:16:18.603
might be better.

397
00:16:18.603 --> 00:16:21.020
And in other cases, you do, sort of, kind of,

398
00:16:21.020 --> 00:16:22.860
you want a lot of fine grain control.

399
00:16:22.860 --> 00:16:25.000
<v ->So is that where some of that frustration</v>

400
00:16:25.000 --> 00:16:27.230
around the lack of controllability

401
00:16:27.230 --> 00:16:28.940
and interpretability comes from?

402
00:16:28.940 --> 00:16:30.100
<v ->Yeah, if you're building a model</v>

403
00:16:30.100 --> 00:16:31.970
that just predicts the next thing

404
00:16:31.970 --> 00:16:34.790
based off of everything it's seen from texts online,

405
00:16:34.790 --> 00:16:37.350
then yeah, you're really gonna be replicating

406
00:16:37.350 --> 00:16:39.550
whatever that distribution online is.

407
00:16:39.550 --> 00:16:42.760
<v ->If you train a model off of language off the internet,</v>

408
00:16:42.760 --> 00:16:45.130
it sometimes says uncomfortable things

409
00:16:45.130 --> 00:16:48.960
or inappropriate things and sometimes really biased things.

410
00:16:48.960 --> 00:16:50.790
Have you ever run into this yourself?

411
00:16:50.790 --> 00:16:52.940
And then how do you think about that problem

412
00:16:52.940 --> 00:16:56.560
of potentially even measuring the bias

413
00:16:56.560 --> 00:16:58.490
in a model that we've trained?

414
00:16:58.490 --> 00:17:01.160
<v ->Yeah, it's a really tricky question.</v>

415
00:17:01.160 --> 00:17:03.720
As you said, these models are trained to, sort of, predict

416
00:17:03.720 --> 00:17:05.340
the next sequence of words,

417
00:17:05.340 --> 00:17:06.910
given a certain sequence of words.

418
00:17:06.910 --> 00:17:09.160
So we could start with just, sort of, prompts

419
00:17:09.160 --> 00:17:11.860
like "the woman was" versus "the man was",

420
00:17:11.860 --> 00:17:13.990
and, kind of, pull out common words

421
00:17:13.990 --> 00:17:15.390
that are, sort of, more used

422
00:17:15.390 --> 00:17:17.710
with one phrase versus the other.

423
00:17:17.710 --> 00:17:20.880
So that's, sort of, a qualitative way of looking at it.

424
00:17:20.880 --> 00:17:24.150
It's not ever kind of a guarantee of how the model

425
00:17:24.150 --> 00:17:26.270
is gonna behave in one particular instance.

426
00:17:26.270 --> 00:17:28.570
And I think that's what's really tricky

427
00:17:28.570 --> 00:17:30.610
and that's why I, sort of, think it's really good

428
00:17:30.610 --> 00:17:33.720
for creators of systems to just be honest

429
00:17:33.720 --> 00:17:36.270
about, "This is, sort of, what we have seen."

430
00:17:36.270 --> 00:17:38.677
And so then, someone can make their own judgment about,

431
00:17:38.677 --> 00:17:40.310
"Is this gonna be too high risk

432
00:17:40.310 --> 00:17:42.740
for, sort of, my particular use case?"

433
00:17:42.740 --> 00:17:44.340
<v ->I imagine in the last few years,</v>

434
00:17:44.340 --> 00:17:47.070
we've seen a lot of changes and improvements

435
00:17:47.070 --> 00:17:49.960 line:15% 
in the capabilities of NLP systems.

436
00:17:49.960 --> 00:17:51.570 line:15% 
So is there anything in that

437
00:17:51.570 --> 00:17:54.510
that you're particularly excited about exploring further?

438
00:17:54.510 --> 00:17:59.510
<v ->I'm really interested in, sort of, the creative potential</v>

439
00:18:00.280 --> 00:18:02.980
that we've started to see from NLP systems

440
00:18:02.980 --> 00:18:04.490
with things like GPT-3

441
00:18:04.490 --> 00:18:06.210
and other really powerful language models.

442
00:18:06.210 --> 00:18:10.990
It's really easy to write long grammatical passages

443
00:18:10.990 --> 00:18:13.580
thinking about the way that we can then harness, like,

444
00:18:13.580 --> 00:18:16.320
the human ability to actually give meaning to those words

445
00:18:16.320 --> 00:18:17.950
and, sort of, provide structure

446
00:18:17.950 --> 00:18:20.640
and how we can combine those things with the, kind of like,

447
00:18:20.640 --> 00:18:22.930
generative capabilities of these models now

448
00:18:22.930 --> 00:18:23.860
is really interesting.

449
00:18:23.860 --> 00:18:24.900
<v ->Yeah, I agree.</v>

450
00:18:24.900 --> 00:18:27.720 line:15% 
[quirky music]

451
00:18:27.720 --> 00:18:29.437
So, hi Claudia. It's so great to see you.

452
00:18:29.437 --> 00:18:30.930
<v ->It has been far too long.</v>

453
00:18:30.930 --> 00:18:33.500
<v ->You know, we first met 10, 11 years ago</v>

454
00:18:33.500 --> 00:18:36.810
and machine learning has changed a lot since then.

455
00:18:36.810 --> 00:18:39.850 line:15% 
<v ->Tooling that we now have, the capacity,</v>

456
00:18:39.850 --> 00:18:43.520 line:15% 
and also, an elevation of the problem sets

457
00:18:43.520 --> 00:18:47.150 line:15% 
that we're dealing with and how to frame the problem.

458
00:18:47.150 --> 00:18:50.730
And I'm almost struggling to figure out

459
00:18:50.730 --> 00:18:54.670
whether it's a blessing or curse that it has become

460
00:18:54.670 --> 00:18:59.670
as accessible and as democratized and as easy to execute

461
00:18:59.830 --> 00:19:03.000
and you just build another new company from scratch.

462
00:19:03.000 --> 00:19:05.450
And so, what's been, kind of, your reflection on that?

463
00:19:05.450 --> 00:19:07.890
<v ->Well, you're absolutely right that the attention</v>

464
00:19:07.890 --> 00:19:10.970
machine learning gets has grown dramatically.

465
00:19:10.970 --> 00:19:12.730
20 years ago, going to gatherings

466
00:19:12.730 --> 00:19:14.420
and telling people what I was working on

467
00:19:14.420 --> 00:19:16.040
and seeing the blank face or the like,

468
00:19:16.040 --> 00:19:18.030
"Where's the turn?" and walk away.

469
00:19:18.030 --> 00:19:19.570
Like, "Oh, no."

470
00:19:19.570 --> 00:19:21.130
The accessibility of the tooling,

471
00:19:21.130 --> 00:19:24.670
like, we can now do in, like, five lines of code

472
00:19:24.670 --> 00:19:27.510
something that would have taken 500 lines

473
00:19:27.510 --> 00:19:30.180
of very mathematical, messy, gnarly code

474
00:19:30.180 --> 00:19:32.150
even, you know, five years ago.

475
00:19:32.150 --> 00:19:33.750
And that's not an exaggeration.

476
00:19:33.750 --> 00:19:36.430
And there are tools that mean that pretty much anyone

477
00:19:36.430 --> 00:19:38.690
can pick this up and start playing with it

478
00:19:38.690 --> 00:19:40.170
and start to build with it.

479
00:19:40.170 --> 00:19:42.530
And that is also really exciting.

480
00:19:42.530 --> 00:19:44.850
<v ->In contrast, what I'm struggling with,</v>

481
00:19:44.850 --> 00:19:46.400
the friend of mine who asked me

482
00:19:46.400 --> 00:19:49.080
to look at some health care data for him.

483
00:19:49.080 --> 00:19:52.020
And despite the capabilities that we're having

484
00:19:52.020 --> 00:19:55.180
in all of the, kind of, bigger societal problems

485
00:19:55.180 --> 00:19:58.480
alongside with data collection engineering,

486
00:19:58.480 --> 00:19:59.960
all the gnarly stuff,

487
00:19:59.960 --> 00:20:02.960
that is actually not the machine learning itself,

488
00:20:02.960 --> 00:20:07.020
it's the rest of it where certain data isn't available.

489
00:20:07.020 --> 00:20:10.140
And to me, it's staggering how difficult it is

490
00:20:10.140 --> 00:20:12.692
to get it off the ground and actually use.

491
00:20:12.692 --> 00:20:15.480
<v ->And part of the challenge of it</v>

492
00:20:15.480 --> 00:20:18.060
is not the mathematics of building models,

493
00:20:18.060 --> 00:20:20.210
but the challenge is making sure that the data

494
00:20:20.210 --> 00:20:23.660
is sufficiently representative, potentially high quality.

495
00:20:23.660 --> 00:20:25.880
<v ->And how transparent do I need to build it</v>

496
00:20:25.880 --> 00:20:28.420
for it to be adopted at some point?

497
00:20:28.420 --> 00:20:32.900
What types of biases in the data collection,

498
00:20:32.900 --> 00:20:34.930
and then also in the usage?

499
00:20:34.930 --> 00:20:37.520
We now call it the bias, but we're still struggling

500
00:20:37.520 --> 00:20:41.880
with the society not really living up to its expectations

501
00:20:41.880 --> 00:20:44.490
and then machine learning, bringing it to the forefront.

502
00:20:44.490 --> 00:20:45.323
<v ->Right.</v>

503
00:20:45.323 --> 00:20:46.460
And so, to say that another way,

504
00:20:46.460 --> 00:20:48.920
when you're collecting data from the real world

505
00:20:48.920 --> 00:20:50.670
and then building machine learning systems

506
00:20:50.670 --> 00:20:52.770
that automate decisions based on that data,

507
00:20:52.770 --> 00:20:55.110
all of the biases and problems

508
00:20:55.110 --> 00:20:58.440
that are already in the real world then can be magnified

509
00:20:58.440 --> 00:21:00.290
through that machine learning system.

510
00:21:00.290 --> 00:21:02.770
And so, it can make many of these problems much worse.

511
00:21:02.770 --> 00:21:05.220
<v ->Feeling increasingly challenged</v>

512
00:21:05.220 --> 00:21:09.150
that my skillset of being very good at programming

513
00:21:09.150 --> 00:21:10.950
has become somewhat secondary.

514
00:21:10.950 --> 00:21:11.936
And it's feeling...

515
00:21:11.936 --> 00:21:12.793
[both laugh]

516
00:21:12.793 --> 00:21:15.790
It's really the bigger picture understanding

517
00:21:15.790 --> 00:21:17.570
of "Who would be using that?

518
00:21:17.570 --> 00:21:19.650
How transparent do I need to build it

519
00:21:19.650 --> 00:21:21.970
for it to be adopted at some point?

520
00:21:21.970 --> 00:21:26.420
What types of biases in the data collection

521
00:21:26.420 --> 00:21:28.050
and then also in the usage?"

522
00:21:28.050 --> 00:21:32.090
I think, in certain areas, we have societal expectations

523
00:21:32.090 --> 00:21:35.040
as to what is fair and what isn't.

524
00:21:35.040 --> 00:21:39.560
<v ->And so, it's not just the provenance of that data,</v>

525
00:21:39.560 --> 00:21:41.307
but it's, sort of, deeply understanding,

526
00:21:41.307 --> 00:21:43.160
"Why does it look the way it looks?

527
00:21:43.160 --> 00:21:44.440
Why was it collected this way?

528
00:21:44.440 --> 00:21:46.110
What are the limitations of it?"

529
00:21:46.110 --> 00:21:47.200
We need to think about that

530
00:21:47.200 --> 00:21:51.460
in entire process, how we document that process.

531
00:21:51.460 --> 00:21:53.010
This is an issue in companies

532
00:21:53.010 --> 00:21:55.150
where somebody might create something

533
00:21:55.150 --> 00:21:57.470
that even their peers can't recreate.

534
00:21:57.470 --> 00:22:00.800
<v ->What have you seen in terms of which industries,</v>

535
00:22:00.800 --> 00:22:03.610
where they stand, like who is adopting now?

536
00:22:03.610 --> 00:22:06.550
Who is ready to utilize it?

537
00:22:06.550 --> 00:22:09.158
Where would you maybe wish that didn't even try?

538
00:22:09.158 --> 00:22:10.330
[Hilary laughs]

539
00:22:10.330 --> 00:22:11.550
<v ->These are great questions.</v>

540
00:22:11.550 --> 00:22:14.960
So things like actuarial science, operations research,

541
00:22:14.960 --> 00:22:17.240
where they actually are not using machine learning

542
00:22:17.240 --> 00:22:18.560
as much as you might think.

543
00:22:18.560 --> 00:22:21.460
And then you have other sorts of companies

544
00:22:21.460 --> 00:22:24.930
or on the FinTech side, or even the ad tech side of things

545
00:22:24.930 --> 00:22:27.810
where they perhaps are using machine learning

546
00:22:27.810 --> 00:22:30.030
to the point of even absurdity.

547
00:22:30.030 --> 00:22:33.930
<v ->So I spent about eight years working in ad tech.</v>

548
00:22:33.930 --> 00:22:37.280
And the motivation was really

549
00:22:37.280 --> 00:22:41.330
because it was such an amazingly exciting playground

550
00:22:41.330 --> 00:22:43.720
to push that technology

551
00:22:43.720 --> 00:22:47.053
that used to largely live in academia, really,

552
00:22:47.920 --> 00:22:50.820
out in the world and see, kind of, what it can achieve.

553
00:22:50.820 --> 00:22:53.870
It has created such a hunger for data

554
00:22:53.870 --> 00:22:56.890
that now everything is being collected.

555
00:22:56.890 --> 00:22:59.660
I'm curious, when are we going to

556
00:23:01.080 --> 00:23:03.820
make a foray into things like agriculture

557
00:23:03.820 --> 00:23:08.420
about smart production of the things we eat?

558
00:23:08.420 --> 00:23:10.440
You see and hear these interesting stories,

559
00:23:10.440 --> 00:23:13.030
but I feel like we're not ready yet

560
00:23:13.030 --> 00:23:17.680
to put that into a economically viable situation.

561
00:23:17.680 --> 00:23:20.900
<v ->So when we think about the next five to 10 years,</v>

562
00:23:20.900 --> 00:23:24.030
the things that are really still holding us back

563
00:23:24.030 --> 00:23:29.030
are these uneven applications of resources to problems

564
00:23:30.040 --> 00:23:31.850
because the problems that get attention

565
00:23:31.850 --> 00:23:33.280
are the high value ones

566
00:23:33.280 --> 00:23:35.430
in terms of how much money you can make

567
00:23:35.430 --> 00:23:37.040
or the things that are fashionable enough

568
00:23:37.040 --> 00:23:38.760
that you can publish a paper on it.

569
00:23:38.760 --> 00:23:40.890
So what do you think is holding us back?

570
00:23:40.890 --> 00:23:44.370
<v ->I fully agree on the steps you pointed out</v>

571
00:23:44.370 --> 00:23:45.910
and the processes.

572
00:23:45.910 --> 00:23:48.130
I think there is a chicken and egg problem,

573
00:23:48.130 --> 00:23:49.430
like your former example,

574
00:23:49.430 --> 00:23:54.430
that these areas that need to wait for data,

575
00:23:54.740 --> 00:23:56.530
the value of the data collection

576
00:23:56.530 --> 00:23:59.470
is then also slightly less apparent.

577
00:23:59.470 --> 00:24:01.040
And so, it gets delayed further

578
00:24:01.040 --> 00:24:02.890
and you'll see that happening.

579
00:24:02.890 --> 00:24:05.500
But what my experience has been,

580
00:24:05.500 --> 00:24:09.110
there's unfortunately, I feel a drifting apart

581
00:24:09.110 --> 00:24:10.820
between academia

582
00:24:10.820 --> 00:24:14.120
and the uses of AI,

583
00:24:14.120 --> 00:24:19.120
but I am somewhat frustrated with a generation of students

584
00:24:19.290 --> 00:24:22.860
who have standard data sets that they never think about

585
00:24:22.860 --> 00:24:25.190
what the model needs to be used for,

586
00:24:25.190 --> 00:24:26.740
that they never have to think about

587
00:24:26.740 --> 00:24:28.360
how the data was collected.

588
00:24:28.360 --> 00:24:31.180
So with all of these challenges ahead of us,

589
00:24:31.180 --> 00:24:34.330
how optimistic are you about this world

590
00:24:34.330 --> 00:24:38.110
that I deeply believe we can create

591
00:24:38.110 --> 00:24:40.500
and the steps towards it?

592
00:24:40.500 --> 00:24:43.440
<v ->I am incredibly optimistic and not...</v>

593
00:24:43.440 --> 00:24:46.980
Perhaps it's a personality flaw, but I can't help but look

594
00:24:46.980 --> 00:24:51.980
at the potential of the technology to reduce harm,

595
00:24:52.250 --> 00:24:55.460
to give us information that help us make better decisions.

596
00:24:55.460 --> 00:24:57.770
And to think that we would choose

597
00:24:57.770 --> 00:25:01.100
to address the big problems ahead of us.

598
00:25:01.100 --> 00:25:03.350
I don't think we have a hope of addressing them

599
00:25:03.350 --> 00:25:05.010
without figuring out the role

600
00:25:05.010 --> 00:25:06.600
that machine learning will play.

601
00:25:06.600 --> 00:25:09.320
And to think that we would then choose not to do that

602
00:25:09.320 --> 00:25:10.700
is just unthinkable.

603
00:25:10.700 --> 00:25:14.950
<v ->Despite that the rightfully raised concerns</v>

604
00:25:14.950 --> 00:25:16.210
about the challenges ahead,

605
00:25:16.210 --> 00:25:20.300
but I think they also make us as a society better.

606
00:25:20.300 --> 00:25:23.260
They challenge us to be a lot clearer

607
00:25:23.260 --> 00:25:26.940
of what fairness means to all of us.

608
00:25:26.940 --> 00:25:30.440
So with all of the setbacks,

609
00:25:30.440 --> 00:25:33.840
I think we have exciting years to come.

610
00:25:33.840 --> 00:25:37.810
And I am looking forward to a world where a lot more of that

611
00:25:37.810 --> 00:25:40.288
is used for the right purposes.

612
00:25:40.288 --> 00:25:43.455
[gentle upbeat music]

613
00:25:45.450 --> 00:25:48.410
<v ->I hope you learned something about machine learning.</v>

614
00:25:48.410 --> 00:25:51.570
There has never been a better time to study machine learning

615
00:25:51.570 --> 00:25:54.160
because you're now able to build products

616
00:25:54.160 --> 00:25:57.210
that have tremendous potential and impact

617
00:25:57.210 --> 00:26:01.323
across any industry or area that you might be excited about.

