Mather, M., Shafir, E. & Johnson, M.K. (2000). Misremembrance of options past: Source
monitoring and choice. Psychological Science,11, 132-138.

This article talks about how people remember the choices that they've made in the past.  The authors argue that remembering one's choices is important for two different reasons...

Self enhancement effects: Remembering a smart choice will make you feel good, remembering a lousy choice makes you feel like kind of a loser.
Problem Solving/Pragmatic: Remembering a choice you've made allows you to reason about similar cases in the future and advice people in similar situations about what choices they should make.
Memory for choice can at times be inaccurate
After having made a choice, people may remember supporting evidence for the choice better than disconfirming evidence.

Or people may do the opposite, concentrating on the opportunity cost of the choice that they made.

People may remember both the positive and negative aspects of the option chosen better than the option not chosen

Source Monitoring and Choice
Mather, et. al argue that there's another way memory for choice may be distorted.  People may mistakenly attribute the characteristics of one option (e.g. job candidate A) to another option (e.g. job candidate B)

Why would this happen?  Having decided on choice A, one may attribute laudable characteristics of choice B to choice A (if you are uncertain as to which of the two has that characteristic)

Method
Four different scenarios were created (job candidate, blind date, roommate I, roommate II).  In each chase, participants read scenarios in which they had to make a choice.

For instance, in the blind date scenario participants were asked to decide between two potential blind dates.  Each had several positive characteristics and some negative characteristics. After a filer period participants were shown a list of features and asked to decide which potential blind date the feature belonged to or whether it belonged to neither of them.

Results
They used a measure they called an Asymmetry Score.  This was calculated by subtracting the attributions that favored option B from the attributions that favored option A.
Attributions Favoring Option A: Attributing a postive feature to A or a negative feature to B
Attributions Favoring Optoin B: Attributing a postive feature to B or a negative feature to A
So the equation they used was
(Pos attributed to A + Neg attributed to B)-(Pos attributed to B + Neg attributed to A)1
This score was then standardized by converting it to a z score, and then converted so that positive asymmetry scores meant tending to make attributions that are consistent with your prior choice.

In each scenario, the asymmetry score was positive (choice consistent) and significantly greater than zero.  This occurred for...

Correct attributions
Misattributions of old items
Misattributions of new items
Discussion
People made  source monitoring errors which were consisten with the choices that they had already made.

These errors may occur in order to support well being, to convince yourself that you were right when you made your decision and to reduce the possibility of "buyer's remorse"

1Strictly speaking it wasn't the number of features used in this analysis but rather the proportion of features
 



 
University of Arkansas
Department of Psychology
Lampinen Lab
False Memory Reading Group
False Memory Reading Group Fall 2000