Monthly Archives: November 2007

The affect heuristic is how an overall feeling of goodness or badness contributes to many other judgments, whether it’s logical or not, whether you’re aware of it or not.  Subjects told about the benefits of nuclear power are likely to rate it as having fewer risks; stock analysts rating unfamiliar stocks judge them as generally good or generally bad – low risk and high returns, or high risk and low returns – in defiance of ordinary economic theory, which says that risk and return should correlate positively.

The halo effect is the manifestation of the affect heuristic in social psychology.  Robert Cialdini, in Influence: Science and Practice, summarizes:

Research has shown that we automatically assign to good-looking individuals such favorable traits as talent, kindness, honesty, and intelligence (for a review of this evidence, see Eagly, Ashmore, Makhijani, & Longo, 1991).  Furthermore, we make these judgments without being aware that physical attractiveness plays a role in the process.  Some consequences of this unconscious assumption that "good-looking equals good" scare me.  For example, a study of the 1974 Canadian federal elections found that attractive candidates received more than two and a half times as many votes as unattractive candidates (Efran & Patterson, 1976).  Despite such evidence of favoritism toward handsome politicians, follow-up research demonstrated that voters did not realize their bias.  In fact, 73 percent of Canadian voters surveyed denied in the strongest possible terms that their votes had been influenced by physical appearance; only 14 percent even allowed for the possibility of such influence (Efran & Patterson, 1976).  Voters can deny the impact of attractiveness on electability all they want, but evidence has continued to confirm its troubling presence (Budesheim & DePaola, 1994).

Continue reading "The Halo Effect" »

Followup to:  Evaluability

"Psychophysics", despite the name, is the respectable field that links physical effects to sensory effects.  If you dump acoustic energy into air – make noise – then how loud does that sound to a person, as a function of acoustic energy?  How much more acoustic energy do you have to pump into the air, before the noise sounds twice as loud to a human listener?  It’s not twice as much; more like eight times as much.

Acoustic energy and photons are straightforward to measure.  When you want to find out how loud an acoustic stimulus sounds, how bright a light source appears, you usually ask the listener or watcher.  This can be done using a bounded scale  from "very quiet" to "very loud", or "very dim" to "very bright".  You can also use an unbounded scale, whose zero is "not audible at all" or "not visible at all", but which increases from there without limit.  When you use an unbounded scale, the observer is typically presented with a constant stimulus, the modulus, which is given a fixed rating.  For example, a sound that is assigned a loudness of 10.  Then the observer can indicate a sound twice as loud as the modulus by writing 20.

And this has proven to be a fairly reliable technique.  But what happens if you give subjects an unbounded scale, but no modulus?  0 to infinity, with no reference point for a fixed value?  Then they make up their own modulus, of course.  The ratios between stimuli will continue to correlate reliably between subjects.  Subject A says that sound X has a loudness of 10 and sound Y has a loudness of 15.  If subject B says that sound X has a loudness of 100, then it’s a good guess that subject B will assign loudness in the range of 150 to sound Y.  But if you don’t know what subject C is using as their modulus – their scaling factor – then there’s no way to guess what subject C will say for sound X.  It could be 1.  It could be 1000.

For a subject rating a single sound, on an unbounded scale, without a fixed standard of comparison, nearly all the variance is due to the arbitrary choice of modulus, rather than the sound itself.

"Hm," you think to yourself, "this sounds an awful lot like juries deliberating on punitive damages.  No wonder there’s so much variance!"  An interesting analogy, but how would you go about demonstrating it experimentally?

Continue reading "Unbounded Scales, Huge Jury Awards, & Futurism" »

Followup to:  The Affect Heuristic

With the expensive part of the Hallowthankmas season now approaching, a question must be looming large in our readers’ minds:

“Dear Overcoming Bias, are there biases I can exploit to be seen as generous without actually spending lots of money?”

I’m glad to report the answer is yes!  According to Hsee (1998) – in a paper entitled “Less is better:  When low-value options are valued more highly than high-value options” – if you buy someone a $45 scarf, you are more likely to be seen as generous than if you buy them a $55 coat.

This is a special case of a more general phenomenon.  An earlier experiment, Hsee (1996), asked subjects how much they would be willing to pay for a second-hand music dictionary:

• Dictionary A, from 1993, with 10,000 entries, in like-new condition.
• Dictionary B, from 1993, with 20,000 entries, with a torn cover and otherwise in like-new condition.

The gotcha was that some subjects saw both dictionaries side-by-side, while other subjects only saw one dictionary…

Continue reading "Evaluability (And Cheap Holiday Shopping)" »

The affect heuristic is when subjective impressions of goodness/badness act as a heuristic – a source of fast, perceptual judgments.  Pleasant and unpleasant feelings are central to human reasoning, and the affect heuristic comes with lovely biases – some of my favorites.

Let’s start with one of the relatively less crazy biases.  You’re about to move to a new city, and you have to ship an antique grandfather clock.  In the first case, the grandfather clock was a gift from your grandparents on your 5th birthday.  In the second case, the clock was a gift from a remote relative and you have no special feelings for it.  How much would you pay for an insurance policy that paid out $100 if the clock were lost in shipping?  According to Hsee and Kunreuther (2000), subjects stated willingness to pay more than twice as much in the first condition.  This may sound rational – why not pay more to protect the more valuable object? – until you realize that the insurance doesn’t protect the clock, it just pays if the clock is lost, and pays exactly the same amount for either clock.  (And yes, it was stated that the insurance was with an outside company, so it gives no special motive to the movers.)

All right, but that doesn’t sound too insane.  Maybe you could get away with claiming the subjects were insuring affective outcomes, not financial outcomes – purchase of consolation.

Then how about this?  Yamagishi (1997) showed that subjects judged a disease as more dangerous when it was described as killing 1,286 people out of every 10,000, versus a disease that was 24.14% likely to be fatal.  Apparently the mental image of a thousand dead bodies is much more alarming, compared to a single person who’s more likely to survive than not.

But wait, it gets worse.

Continue reading "The Affect Heuristic" »