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2-4-6 Game�Confirmation Bias

In-Class Activity

Katie Hope Grobman

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What Sequences Make Me Happy?

2,4,6

☺

count up by 2’s

50%

__,__,__

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VERBAL INSTRUCTIONS:

A sequence of numbers has an order to it. For example, 1-2-3 is a different sequence from 3-2-1.

Some sequences of 3 numbers make me incredibly happy; other sequences of 3 numbers make me very sad.

Your goal is to figure out the rule for what sequences make me happy.

But you can’t simply ask me my rule. Instead you can conduct experiments on me. You can make up a 3 number sequence and I’ll tell you if it makes me happy. Then you can make up another sequence, I’ll tell you again, and we’ll keep going until you’re mostly confident you know the rule inside my head.

Let’s do the first sequence together. 2-4-6 (gesture to the pre-written cell on the handout). After you write a sequence I’ll write a happy or sad face for you in the “fits my rule” column (gesture to the pre-written cell on the handout). It turns out this sequence makes me very happy!

Now that you have feedback from me, you should make your best guess for the rule that makes me happy. For example, you might guess, “counting up by 2’s.” If that’s your guess write it in this blank (gesture to cell), or you can feel free to write another hypothesis (wait for participant to write hypothesis).

To finish the row, you should make a rough estimate for how certain you are the rule you guessed really is the rule for sequences making me happy (gesture to cell). If you have absolutely no confidence and your guess is basically random, write 0%. On the other hand, if you are totally sure you have it, write 100%. You can also write anything in between, such as 50% (wait for participant to write percent).

Now let’s continue. Write a sequence of 3 numbers to test. Once I give you feedback with a happy or sad face, write your hypothesis. If it’s the same as before, feel free to put ditto marks. Say how sure you are with a percent.Then make another sequence to test what rule makes me happy. Wait for my feedback. And so forth. Once you’re nearly 100% confident we’ll stop.

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What Sequences Make Me Happy?

Write a 3 number sequence.
Wait for me to tell you if it fits my rule ☺, or not ☹.
Take your best guess for what my rule is.
Estimate your confidence from 0% to 100%

Repeat the steps.

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If you have a class of about a dozen students, it is pretty easy to cycle through students for many rounds. If you have two dozen students, this requires you to cycle pretty quickly to avoid students getting bored. I suggest you make sure people put backpacks and other obstacles under desks before you begin. I also recommend just saying, “happy” or “sad” softly to students an have them fill in the column. This speeds up your pace. If you have three dozen or more students, I recommend having help such as a TA’s or former students who can divide up the room with you. I’ll give you the rule below; I recommend you generate one sequence now so you can experience a little of the game.

Normally I only play for about 5 rounds. At this point about half the class is 100% sure and most of the rest have a high percent. It’s helpful if you make a mental note of who in your class has the correct answer before you poll the class.

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What Sequences Make Me Happy?

Poll of Our Class:

Guess What Rule Makes Me Happy	N
count up by 2’s
count up by X’s
a formula like (a,b,c) 🡺 a+b=c


any increasing sequence

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What Sequences Make Me Happy?

2,4,6

☺

count up by 2’s

50%

__,__,__

Any increasing sequence of numbers.

Why did so many of you become so confident about a wrong answer?

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Typical Response

2,4,6

☺

count up by 2’s

50%

8,10,12

☺

count up by 2’s

60%

10,12,14

☺

count up by 2’s

70%

20,22,24

☺

count up by 2’s

80%

96,98,100

☺

count up by 2’s

90%

42,44,46

☺

count up by 2’s

100%

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The Hallmark of Science

falsifiability - a clear possibility our hypothesis could be wrong. It's why

We support our hypothesis is true by actively seeking evidence our hypothesis is false. But do we?

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It’s usually a bit more challenging for students to figure out how they should have played to figure out my rule. Draw out of students how they need to actively challenge their preconception by conducting experiments that could falsify their hypothesis.

The hallmark of every science - psychology, physics, and every other - is falsifiability - a clear possibility our hypothesis could be wrong. It's why, in Psychology, we always set up our hypothesis (e.g., bar P is higher than bar Q) against a null (e.g., bar P and Q are the same) and we either reject the null (falsify it) or fail to reject the null (haven't found evidence falsifying it yet).

More simply stated, the only way to show we’re right, is to try and show we’re wrong but fail. That means, with each sequence ("experiment") we need to try and find a possible sequence where we're wrong (see figure 4, ideal play). So if I think its counting up by two's I need a test that's anything but counting up by two's. Notice how counter-intuitive that sounds? That's highlighting just how intuitive the confirmation bias is.

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Science vs Confirmation Bias

2,4,6

☺

count up by 2’s

50%

5,10,15

☺

count up by X’s

50%

3,7,10

☺

the first two add to the third

50%

4,25,100

☺

operation combines 1^st two for 3^rd

50%

3,2,1

☺

any sequence going up

50%

3,20,700

☹

any sequence going up

55%

3,1,2

☹

any sequence going up

6%

2,2,2

☹

any sequence going up

65%

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A World Full of Confirmation Bias

Festinger, Riecken, & Schacter (1956)

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Is the confirmation bias merely a neat trick we can use to fool people in a little game? Or is it more broadly applicable to everyday life? Examples?

The examples students might generate are seemingly endless. Some examples include:

* the appeal of Fox News and MSNBC, whose viewers are mostly those who already agree with their political leanings

* when we search online, we seek information we already agree with or we seek to connect with those we agree with (e.g., social media)

* once we stereotype a group of people, we interpret their actions and circumstances to fit the stereotype (e.g., why are poor people poor)

once we have a reputation (e.g., clumsy, smart) people interpret our actions as fitting their preconception psychiatrists
Social psychologists joined a doomsday cult to see how they would respond when the world did not end on the day they predicted. The cult members rationalized their faith had saved the world.