Archive for January, 2012

A Sermon on Cognitive Bias

Thursday, January 26th, 2012

This is a talk I gave to a group of friends who periodically gather to present TED-style talks. I dressed in a dark suit (uncharacteristic for me) and adopted a solemn demeanor.

Welcome brothers and sisters, to the sermon of the evening. As with many sermons, let us start with a reading from scripture. In this case, my bible is a book called “Thinking Fast And Slow” by Nobel prize winner Daniel Kahneman.

A reading from the book of Daniel: (slightly edited for brevity)

An inconsistency is built into the design of our minds. We want pain to be brief and pleasure to last. But our memory has evolved to represent the most intense moment of an episode of pain or pleasure (the peak) and the feelings when the episode was at its end, but ignores the duration of pain or pleasure. This is called duration neglect, and the peak-end rule.

We designed an experiment using a mild form of torture that I will call the cold-hand situation. Participants are asked to hold their hand up to the wrist in painfully cold water until they are invited to remove it. Each participant endured two cold-hand episodes: The short episode consisted of 60 seconds of immersion in water at 14° Celsius, which is experienced as painfully cold, but not intolerable. The long episode lasted 90 seconds. Its first 60 seconds were identical to the short episode. At the end of the 60 seconds, the experimenter opened a valve that allowed slightly warmer water to flow into the tub. During the additional 30 seconds, the temperature of the water rose by roughly 1°, just enough for most subjects to detect a slight decrease in the intensity of pain.
After the second trial, the participants were given a choice about the third trial. They were told that one of their experiences would be repeated exactly, and were free to choose whether to repeat the experience they had had with their left hand or with their right hand. Of course, half the participants had the short trial with the left hand, half with the right; half had the short trial first, half began with the long, etc. This was a carefully controlled experiment.

Fully 80% of the participants who reported that their pain diminished during the final phase of the longer episode opted to repeat it, thereby declaring themselves willing to suffer 30 seconds of needless pain in the anticipated third trial. If we had asked them, “Would you prefer a 90-second immersion or only the first part of it?” they would certainly have selected the short option. We did not use these words, however, and the subjects did what came naturally: they chose to repeat the episode of which they had the less aversive memory. The subjects knew quite well which of the two exposures was longer—we asked them— but they did not use that knowledge. Rules of memory – the peak-end rule, and duration neglect – determined how much they disliked the two options, which in turn determined their choice.

Now think about this in the context of some of the decisions you have seen at work, at home, in your social life. When your friend decides to manage another product launch, they are remembering that the last product launch was successful, not the fact that they worked with jerks every day for 3 years. People endure tedium in line for hours to get a glimpse of their favorite celebrity, but only remember how exciting the experience was.

So, now that you know about the peak-end rule, and duration neglect, and I’ve given you some examples, you’ll never make these kinds of mistakes again, right? Wrong.

Here’s the real problem: not only are we blind to these cognitive biases, but we are blind to our blindness. We are confident, even when we are wrong. The only way to avoid them is to constantly question our own thinking, would would be impossibly tedious and inefficient.

But here’s the good news: it is easier, and more fun, to recognize other people’s mistakes than our own. The problem here is it is hard to talk about errors in judgement with other people. Most people would naturally respond with rationalization and defensiveness.

So here’s what I am giving you: a name for this cognitive bias, duration neglect. By naming it, we make it easier to recognize and talk about. And instead of being a mistake, it’s more like a medical condition. Gently saying you’re suffering from duration neglect is more like saying you’re suffering from a runny nose, it’s something over which you have no control, and we can work together to mitigate the effects. And hopefully make better decisions.

To come back to the book of Daniel: “My hope is that by giving you the vocabulary to discuss these and the ability to recognize and name them, we can create a community in which we can help each other avoid or at least mitigate these challenges and limit the potential damage.”

Your brain has blind spots, one of these is duration neglect, which can sometimes result in poor decision making. Avoiding these kinds of biases is almost impossible – they are hardwired into your brain. However, you can often see them in others, and with a little humor and humility, you can sometimes help them avoid bad decisions.

So here is the lesson I leave you with: to err is human. To – gently, candidly, humbly – help someone avoid an error, divine.