Noise: A Flaw in Human Judgment

To understand error in judgment, we must understand both bias and noise.

wherever there is judgment, there is noise—and more of it than you think.

There is at least one source of occasion noise that we have all noticed: mood.

Bias and noise—systematic deviation and random scatter—are different components of error.

Causally, noise is nowhere; statistically, it is everywhere.

Most organizations prefer consensus and harmony over dissent and conflict. The procedures in place often seem expressly designed to minimize the frequency of exposure to actual disagreements and, when such disagreements happen, to explain them away.

Life is often more complex than the stories we like to tell about it.

It is more useful to pay attention to people who disagree with you than to pay attention to those who agree.

In a negotiation situation, for instance, good mood helps. People in a good mood are more cooperative and elicit reciprocation. They tend to end up with better results than do unhappy negotiators.

people are rarely aware of their own biases when they are being misled by them. This lack of awareness is itself a known bias, the bias blind spot. People often recognize biases more easily in others than they do in themselves

Averaging two guesses by the same person does not improve judgments as much as does seeking out an independent second opinion. As Vul and Pashler put it, “You can gain about 1/10th as much from asking yourself the same question twice as you can from getting a second opinion from someone else.” This is not a large improvement. But you can make the effect much larger by waiting to make a second guess.

There is good reason to believe that general intelligence is likely to be associated with better judgment. Intelligence is correlated with good performance in virtually all domains. All other things being equal, it is associated not only with higher academic achievement but also with higher job performance.

people who make judgments behave as if a true value exists, regardless of whether it does.

it is hard to agree with reality if you cannot agree with yourself.

On the other hand, a good mood makes us more likely to accept our first impressions as true without challenging them.

When the facts change, I change my mind. What do you do?”)

Noise is mostly a by-product of our uniqueness, of our “judgment personality.

In terms of noise, psychiatry is an extreme case.

good judgments depend on what you know, how well you think, and how you think.

Scientists in diverse disciplines were quick to adopt the least squares method. Over two centuries later, it remains the standard way to evaluate errors wherever achieving accuracy is the goal.

When physicians are under time pressure, they are apparently more inclined to choose a quick-fix solution, despite its serious downsides.

When Vul and Pashler let three weeks pass before asking their subjects the same question again, the benefit rose to one-third the value of a second opinion.

Judgment is not a synonym for thinking, and making accurate judgments is not a synonym for having good judgment.

People cannot be faulted for failing to predict the unpredictable, but they can be blamed for a lack of predictive humility.

Judgment can therefore be described as measurement in which the instrument is a human mind.

if we want people to feel that they have been treated with respect and dignity, we might have to tolerate some noise.

Whatever their flaws, rankings are less noisy than ratings.

There is essentially no evidence of situations in which people do very poorly and models do very well with the same information.

chance variation in a small number of early movers” can have major effects in tipping large populations

objective ignorance accumulates steadily the further you look into the future.