I have been (quite sadly) fascinated by mental anchoring systems for years. This relates to how you can develop quite quickly a fixed perspective on something with no rational reason for it whatsoever.
This came to a head with a Maths lesson I was teaching Year 6 on estimating, and the reading of Alex Bellos’ brilliant book “Alex’s Adventures in Numberland”, which noted that a strong correlation had been found between estimating ability and actual computational ability.
I decided to test the theories out by asking the children in the class to estimate how much an antique book my wife bought for me on ebay cost. I gave them a description of it, and told them that it cost between £1 and £99. It would make sense to suggest that they could have picked any number at all between these two points, so I would have a fairly random ‘spread’ of numbers.
What I did beforehand completely changed that. Before their book price estimation, I asked them to write down the last two digits of their phone numbers. I then explained the ‘Price a book’ challenge, and asked them to write down how much they thought it cost.
The Anchor theory suggested that the random number they first put down would influence the price that they put for the book, even though there was no relation to each of the numbers at all.
The results were startling. I had expected some correlation, but almost every single pupil had put an estimate within around £5 of their (utterly random) telephone number! I drew a chart on the board with two Y axes and joined each pair together to show them visually what they had subconsciously done.
Apologies for the quality of image!
The two exceptions to the anchoring wall were ones which began with very low numbers. Their estimates were wildly higher, presumably because they felt that they anchor was too low to be related to the value of an Antique book.
Although it was fascinating to see happen, and created a lot of debate on what guided our estimating skills in class, it did make me think how easily manipulated children can be by anchored expectations. A simple random number governed their estimating skills. How often do we as teachers take advantage of this and use simple techniques to raise expectations within the children themselves? What do we do to ensure that the children have a growth outlook on their ability, rather than a fixed outlook which dictates what they believe they are capable of achieving?
No answers here from me, but hopefully something to consider!
Further reading:
Gorn, Gerald J, and Marvin E Goldberg. “The impact of television advertising on children from low income families.” Journal of Consumer Research (1977): 86-88.
James, Oliver. “Evaluating the expectations disconfirmation and expectations anchoring approaches to citizen satisfaction with local public services.” Journal of Public Administration Research and Theory 19.1 (2009): 107-123.
Lohrmann, Sharon, and Janet Talerico. “Anchor the Boat A Classwide Intervention to Reduce Problem Behavior.” Journal of Positive Behavior Interventions 6.2 (2004): 113-120.
Switzer, Fred S, and Janet A Sniezek. “Judgment processes in motivation: Anchoring and adjustment effects on judgment and behavior.” Organizational Behavior and Human Decision Processes 49.2 (1991): 208-229.

