CRITICAL THINKING - Cognitive Biases: Anchoring [HD] - YouTube

Channel: Wireless Philosophy

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(intro music)
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My name is Laurie Santos.
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I teach psychology at Yale University, and today
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I want to talk to you about anchoring.
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This lecture is part of a series on cognitive biases.
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Let's do a math problem. really quickly, and you've
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gotta do it in your head
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Ready?
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First, multiply the following numbers: eight times seven times six
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times five times four times three times two times one.
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OK, that's it.
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What's your guess?
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A thousand?
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Two thousand?
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When the psychologists Danny Kahneman and Amos Tversky tried this with
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human subjects, subjects on average
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guessed about two thousand two hundred and fifty.
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Seems like an OK guess.
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But now, let's suppose I gave you a different math problem.
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What if I gave you this one?
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Ready?
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One times two times three times four
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times five times six times seven times eight.
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What's your answer?
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If you're like Kahneman and Tversky's
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subjects, your answer might be a bit different here.
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For this question, their subjects guessed a lot lower.
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On average they said the answer was about five hundred and twelve.
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The first amazing thing about these similar
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mathematical estimates is that people get the answers really, really wrong.
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In fact, the real answer?
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Well, for both, its forty thousand three hundred and twenty.
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People are off by an order of magnitude.
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But the second, even more amazing thing is that people give
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different answers to the two problems, even though they're just different ways
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of asking exactly the same question.
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Why do we give completely different answers,
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when the same math problem is presented differently?
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The answer lies in how we make estimates.
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When you have lots of time to do a math
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problem, like eight times seven times six times five times four times three times
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two times one, you can multiply all of
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the numbers together and get an exact product.
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But when you have to do the problem
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quickly, you don't really have time to finish.
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So you start with the first numbers.
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You multiply eight times seven, and get fifty-six.
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And then you've gotta multiply that by six,
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and, well, you're guessing the final number's gotta be pretty big, bigger than
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fifty-six, like maybe two thousand or so.
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But when you do the second problem, you start
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with one times two, and, well, that's only two, and two times three's only six.
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Your answer's gonna be pretty small,
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maybe only like five hundred or so.
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This process of guessing based on the first
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number you see is what's known as "anchoring."
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The first number we think of
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when we do our estimate is the anchor.
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And once we have an anchor in our head,
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well, we sort of adjust as needed from there.
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The problem is that our minds are biased not to adjust as much as we need to.
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The anchors are cognitively really strong.
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In the first, problem you probably started with fifty-six, and
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then adjusted to an even bigger number from there.
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And in the second problem, you started with six, and then adjusted from there.
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The problem is that starting at different points leads to different final guesses.
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Like real anchors, our estimated anchors kinda get us stuck in one spot.
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We often fail to drag the anchor far enough to get to a correct answer.
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Kahneman and Tversky discovered that this
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sort of anchoring bias happens all the time,
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even for anchors that are totally arbitrary.
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For example, they asked people to spin a wheel with
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numbers from one to a hundred, and then asked them to estimate
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what percentage of countries in the United Nations are African.
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People who spun a ten on the wheel estimated that
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the number was about twenty-five percent.
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But people who spun a sixty-five estimated that
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the number was forty-five percent.
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In another experiment, Dan Ariely and his colleagues had people
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write down the last two digits of their social security number.
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They were then asked whether they would
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pay that amount in dollars for a nice bottle of wine.
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Ariely and colleagues found that people in the highest quintile of social security
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numbers would pay three to four times as much for the exact same good.
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Just setting up a larger anchor can make a
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person who would pay eight dollars for the bottle
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of wine be willing to spend twenty-seven dollars instead.
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Sadly for us, sales people use anchors against us all the time.
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How many times have you noticed a salesperson or an advertisement
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anchoring you to a particular price, or
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even to how much of a particular product you should buy?
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Whether it's buying a car, or a sweater,
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or even renting a hotel room, our intuitions about what prices
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are reasonable to pay often come from some arbitrary anchor.
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So, the next time you're given an anchor, take a minute to think.
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Remember what happens when you
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drop your anger too high, and then
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consider thinking of a very different number.
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It might affect your final estimate more than you expect.
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