In his fascinating book, Thinking, Fast and Slow, Daniel Kahneman writes of “anchoring.”
His and others’ research has shown that when people are given a starting number about a topic they know little about and then asked a question about the topic, they have a tendency not to drift too far from the given figure. The figure serves as an anchor.
An example he uses:
Is the height of the tallest redwood more or less than 1,200 feet?
What is your best guess about the height of the tallest redwood?
Even though 1,200 feet is a ridiculously large number for the height of a redwood, asking question 1 (Is the height of the tallest redwood more or less than 1,200 feet?) ahead of asking the latter question primes the respondent with some information about the topic and this has a major impact on what their best guess about the height of the tallest redwood will be.
The person being questioned may assume that the person asking the question has some knowledge of redwoods and therefore use 1,200 as their starting place. Knowing enough to assume the given number is too high, they would most likely drop below the initial figure, but not too far below. Rather than starting with their own guess, they use 1,200 as a starting place and as they drop below the starting place, they settle on a number before dipping too far into the uncertain zone. The number then ends up far closer to the starting place than were the person to have come up with a guess all on their own.
The implications of this for teaching are immense. We often ask students to share their thoughts on topics they are just forming opinions on. While exposure to others’ ideas is helpful, it is also helpful for teachers to be aware of the priming effect peers’ responses might have on students. The teacher may also wish to help students identify this effect.
Kahneman notes that even after identifying the effect of “anchors” they still have an impact. Choosing when to have group discussions and being mindful of giving students time to find their own starting place is essential.
I’m in the midst of Kahneman’s book and literally enjoying every page. As we strive to teach students to think critically and creatively, learning more about psychology and the way the brain work is important. There are many tools to assist students with evaluating the perspective and biases of others; what is more difficult is evaluating the way we process information and form conclusions.
So let’s be more realistic this time. Did the tallest redwood even exceed 200 feet? What’s your guess?