You’re a few years behind on this research, Eliezer.
The point of the research program of Mussweiler and Strack is that anchoring effects can occur without any adjustment. “Selective Accessibility” is their alternative, adjustment-free process that can produce estimates that are too close to the anchor. The idea is that, when people are testing the anchor value, they bring to mind information that is consistent with the correct answer being close to the anchor value, since that information is especially relevant for answering the comparative question. Then when they are then asked for their own estimate, they rely on that biased set of information that is already accessible in their mind, which produces estimates that are biased towards the anchor.
In 2001, Epley and Gilovich published their first of several papers designed to show that, while the Selective Accessibility process occurs and creates adjustment-free anchoring effects, there are also cases where people do adjust from an anchor value, just as Kahneman & Tversky claimed. The examples that they’ve used in their research are trivia questions like “What is the boiling point of water on Mount Everest?” where subjects will quickly think of a relevant, but wrong, number on their own, and they’ll adjust from there based on their knowledge of why the number is wrong. In this case, most subjects know that 212F is the boiling point of water at sea level, but water boils at lower temperatures at altitude, so they adjust downward. This anchoring & adjustment process also creates estimates that are biased towards the anchor, since people tend to stop adjusting too soon, once they’ve reached a plausible-seeming value.
Gilovich and Epley have shown that subjects give estimates farther from the anchor (meaning that they are adjusting more) on these types of questions when they are given incentives for accuracy, warned about the biasing effect of anchors, high in Need For Cognition (the dispositional tendency to think things through a lot), or shaking their head (which makes them less willing to stop at a plausible-seeming value; head-nodding produces even less adjustment than baseline). None of these variables matter on the two-part questions with an experimenter provided anchor, like the Africa UN %, where selective accessibility seems to be the process creating anchoring effects. The relevance of these variables is the main evidence for their claim that adjustment occurs with one type of anchoring procedure but not the other.
The one manipulation that has shown some promise at debiasing Selective Accessibility based anchoring effects is a version of the “consider the opposite” advice that Eliezer gives. Mussweiler, Strack & Pfeiffer (2000) argued that this strategy helps make a more representative set of information accessible in subjects’ minds, and they did find debiasing when they gave subjects targeted, question-specific instructions on what else to consider. But they did not try teaching subjects the general “consider the opposite” strategy and seeing if they could successfully apply it to the particular case on their own.
Mussweiler and Gilovich both have all of their relevant papers available for free on their websites.
Epley, N., & Gilovich, T. (2001). Putting adjustment back in the anchoring and adjustment heuristic: Differential processing of self-generated and experimenter-provided anchors. Psychological Science, 12, 391–396.
Mussweiler, T., Strack, F., & Pfeiffer, T. (2000). Overcoming the inevitable anchoring effect: Considering the opposite compensates for selective accessibility. Personality and Social Psychology Bulletin, 26, 1142-1150.
Gilovich and Epley have shown that subjects give estimates farther from the anchor (meaning that they are adjusting more) on these types of questions when they are given incentives for accuracy, warned about the biasing effect of anchors, high in Need For Cognition (the dispositional tendency to think things through a lot), or shaking their head (which makes them less willing to stop at a plausible-seeming value; head-nodding produces even less adjustment than baseline).
Shaking their heads? If this is really an effective way to de-bias your thinking a tiny bit...COOL! I will try that!
There have actually been several studies I’ve seen indicating that body-language is a feedback loop rather than just a communication output. Forcing yourself to smile will actually make you slightly happier, etc.
You’re a few years behind on this research, Eliezer.
The point of the research program of Mussweiler and Strack is that anchoring effects can occur without any adjustment. “Selective Accessibility” is their alternative, adjustment-free process that can produce estimates that are too close to the anchor. The idea is that, when people are testing the anchor value, they bring to mind information that is consistent with the correct answer being close to the anchor value, since that information is especially relevant for answering the comparative question. Then when they are then asked for their own estimate, they rely on that biased set of information that is already accessible in their mind, which produces estimates that are biased towards the anchor.
In 2001, Epley and Gilovich published their first of several papers designed to show that, while the Selective Accessibility process occurs and creates adjustment-free anchoring effects, there are also cases where people do adjust from an anchor value, just as Kahneman & Tversky claimed. The examples that they’ve used in their research are trivia questions like “What is the boiling point of water on Mount Everest?” where subjects will quickly think of a relevant, but wrong, number on their own, and they’ll adjust from there based on their knowledge of why the number is wrong. In this case, most subjects know that 212F is the boiling point of water at sea level, but water boils at lower temperatures at altitude, so they adjust downward. This anchoring & adjustment process also creates estimates that are biased towards the anchor, since people tend to stop adjusting too soon, once they’ve reached a plausible-seeming value.
Gilovich and Epley have shown that subjects give estimates farther from the anchor (meaning that they are adjusting more) on these types of questions when they are given incentives for accuracy, warned about the biasing effect of anchors, high in Need For Cognition (the dispositional tendency to think things through a lot), or shaking their head (which makes them less willing to stop at a plausible-seeming value; head-nodding produces even less adjustment than baseline). None of these variables matter on the two-part questions with an experimenter provided anchor, like the Africa UN %, where selective accessibility seems to be the process creating anchoring effects. The relevance of these variables is the main evidence for their claim that adjustment occurs with one type of anchoring procedure but not the other.
The one manipulation that has shown some promise at debiasing Selective Accessibility based anchoring effects is a version of the “consider the opposite” advice that Eliezer gives. Mussweiler, Strack & Pfeiffer (2000) argued that this strategy helps make a more representative set of information accessible in subjects’ minds, and they did find debiasing when they gave subjects targeted, question-specific instructions on what else to consider. But they did not try teaching subjects the general “consider the opposite” strategy and seeing if they could successfully apply it to the particular case on their own.
Mussweiler and Gilovich both have all of their relevant papers available for free on their websites.
Epley, N., & Gilovich, T. (2001). Putting adjustment back in the anchoring and adjustment heuristic: Differential processing of self-generated and experimenter-provided anchors. Psychological Science, 12, 391–396.
Mussweiler, T., Strack, F., & Pfeiffer, T. (2000). Overcoming the inevitable anchoring effect: Considering the opposite compensates for selective accessibility. Personality and Social Psychology Bulletin, 26, 1142-1150.
Shaking their heads? If this is really an effective way to de-bias your thinking a tiny bit...COOL! I will try that!
There have actually been several studies I’ve seen indicating that body-language is a feedback loop rather than just a communication output. Forcing yourself to smile will actually make you slightly happier, etc.