Disconfirmation Bias
by MikeGeneIn their paper, "A Disconfirmation Bias in the Evaluation of Arguments," psychologists Kari Edwards and Edward Smith (Journal of Personality and Social Psychology, 1996, Vol. 71, No. 1, 5-24) explore this tendency. They begin their article as follows:
When evaluating an argument, can one assess its strength independently of one's prior belief in the conclusion? A good deal f evidence indicates the answer is an emphatic no. This phenomenon, which we refer to as the prior belief effect, has important implications. Given two people, or groups, with opposing beliefs about a social, political, or scientific issue, the degree to which they will view relevant evidence as strong will differ. This difference, in turn, may result in a failure of the opposing parties to converge on any kind of meaningful agreement, and, under some circumstances, they may become more extreme in their beliefs.
Edwards and Smith then summarize a classic experiment by Lord, Ross, and Lopper ( 1979). This study focused on "people's evaluations of arguments about whether the death penalty is an effective deterrent against murder."
They selected two groups of participants, one known to believe that the death penalty is an effective deterrent and one known to believe that it is not an effective deterrent. Both groups were presented with two arguments, one that pointed to the deterrent efficacy of the death penalty and one that pointed to its inefficacy as a deterrent. Each argument consisted of a brief description of the design and findings of a study supporting or opposing the death penalty (e.g., a study showing that a state's murder rate declined after institution of the death penalty) and was followed by criticisms of the study itself, as well as rebuttals of these criticisms. The best-known finding associated with this study is that the pro-death-penalty and anti-death-penalty participants became more polarized in their beliefs– and hence more different from one another–as a result of reading the two arguments. Note, however, that this result is a logical consequence of another more basic finding obtained by Lord et al.: When participants were asked to rate how convincing each study seemed as evidence (i.e., assessments involved participants' judgment of the argument's strength rather than their final belief in the conclusion), proponents of the death penalty judged the pro-death-penalty arguments to be more convincing or stronger than the anti-death-penalty arguments, whereas the opponents of the death penalty judged the anti-death-penalty arguments to be more convincing. This is the prior belief effect, and it has as one of its consequences the polarization of belief.
Edwards and Smith then introduce their model:
When faced with evidence contrary to their beliefs, people try to undermine the evidence. That is, there is a bias to disconfirm arguments incompatible with one's position. This idea can be developed into a disconfirmation model by making the following assumptions.
1. When one is presented an argument to evaluate, there will be some automatic activation in memory of material relevant to the argument. Some of the accessed material will include one's prior beliefs about the issue.
2. If the argument presented is incompatible with prior beliefs, one will engage in a deliberative search of memory for material that will undermine the argument simply. Hence, "scrutinizing an argument" is implemented as a deliberate memory search, and such a search requires extensive processing.
3. Possible targets of the memory search include stored beliefs and arguments that offer direct evidence against the premises and conclusion of the presented argument.
4. The outputs of the memory search are integrated with other (perhaps unbiased) considerations about the current argument, and the resulting evaluation serves as the basis for judgments of the current argument's strength.
Edwards and Smith then conducted two experiments that supported this model and also showed that emotional conviction influences the magnitude and form of the disconfirmation bias.
It makes sense that a disconfirmation bias would exist. If the human brain is wired to defend its preconceptions with confirmation bias, attacking beliefs that threaten those preconceptions would likely be part of the same strategy. This undercuts Michael Shermer's belief that "Skepticism is the antidote for the confirmation bias." In reality, hyper-skepticism, or selectively applied skepticism, may simply be another facet of the same brain processes that generate confirmation bias.
What does disconfirmation bias look like? I would like to propose three possible signs that disconfirmation bias is taking place, where one may be defending their preconceptions more so than playing the honest skeptic who is simply trying to "follow the evidence."
1. According to Edwards and Smith, "When one is presented an argument to evaluate, there will be some automatic activation in memory of material relevant to the argument." Searching one's "memory banks" can easily become relying on stereotypes. A stereotype, after all, is the brain's "summation" of previous experience that is linked by certain cues. Thus, I hypothesize that when one is confronted with an argument that challenges their preconceptions, the more that person relies on stereotypes, the more it is likely they are exhibiting disconfirmation bias to protect a preconception.
How can you tell if stereotype is involved? Often, it is obvious. For example, if a critic on the Internet poses his own argument against my design hypothesis, and I begin to rail against Richard Dawkins, obviously my brain has been tapping into information about Dawkins to interpret my opponent. Often times, however, the evidence is more subtle. And that takes me to my second sign.
2. If one's brain is on "a deliberative search of memory for material that will undermine the argument simply" and the "search include stored beliefs and arguments that offer direct evidence against the premises and conclusion of the presented argument," it stands to reason the person with disconfirmation bias will have a strong tendency to link a current argument with the perceived failures of previously-experienced arguments. This creates a mental inertia that leads to two expressions of disconfirmation bias:
a. Misrepresentation "“ Let's say that Jones develops an argument that threatens the preconceptions of Smith. But let us also say that Smith had previously successfully dismantled a similar, but different, argument that was once posed by Miller. The memory of this experience will shape the way Smith reacts to Jones. The brain processes involved in disconfirmation bias will cause Smith to morph Jones' position into that of Miller's. Smith will feel vindicated by the disconfirmation bias, while Jones will recognize that Smith is attacking a "straw man."
b. Faulty Extrapolation "“ This is a more subtle version of misrepresentation, where Smith's brain is so highly activated that it is sensitized to "cues" from Jones that lead Smith to believe that Jones is reaching for Miller's point. Smith will not focus on the actual argument Jones is making, but will be trying to "anticipate" where he thinks the argument is going in order to cut it off. In this case, Smith is not really disconfirming Jones' argument; he is creating an illusion of disconfirmation in his mind because he thinks he knows where the argument is going (when it may not even be going in that direction).
3. Finally, there is the dead give-away of personal attack. When someone attacks another person by questioning their motivations or with ridicule (and more), they are seeking to discredit the argument by discrediting the person who makes the argument. If such personal attacks are linked to stereotypes, it becomes clear the person's brain is adopting an "end justifies the means" approach to disconfirmation bias.
In summary, skepticism is a good thing, but skepticism can be just another facet of the way brains defend "their territory." Add tribalisitic group behavior to the picture and the whole process is amplified and entrenched. I propose that you can detect disconfirmation bias at work, in individuals or groups, when hyper-skepticism, stereotype, misrepresentation, faulty extrapolations, and personal attacks occur more often than not.
May 29th, 2008 at 10:49 am
Thanks for that, it explains a lot.
Comment by The Pixie — May 29, 2008 @ 10:49 am
May 29th, 2008 at 11:06 am
I wonder what percentage of readers will read this as confirmation of their "knowledge" that the other side is simply biased ;).
Perhaps the most successful tool for countering various forms of bias is to adhere to rigid standards of objective empirical data. Obviously that doesn't apply to all areas of human inquiry (the arts, philosophy) but wherever it can be applied it is a wonderful tool for discovering truth. In other fields where empirical data cannot be applied the best you can hope for is reaching consensus or at least mutual understanding of your differences.
Comment by Todd Berkebile — May 29, 2008 @ 11:06 am
May 29th, 2008 at 11:43 am
Hi Todd,
Yet there is no reason to think adherence "to rigid standards of objective empirical data" is of much help when it comes to the core issues that separate teleologists and non-teleologists. As Monod pointed out, "Hence it is through reference to our own activity, conscious and projective, intentional and purposive-it is as makers of artifacts-that we judge of a given object's "naturalness" or "artificialness.""
I have raised the possibility that we cannot get away from this subjectivity and experience when it comes to such judgments. In fact, as you noted, "in the entire history of humanity no one has figured out an objective way to identify design."
Thus, we are faced with two choices.
Comment by MikeGene — May 29, 2008 @ 11:43 am
May 29th, 2008 at 11:44 am
I had a strong disconfirmation bias in favor of neo-Darwinian orthodoxy until I read Denton, Johnson, Behe, et. al., and found their arguments and evidence persuasive.
[OFF-TOPIC] Bunny news:
http://www.foxnews.com/story/0...
Comment by GilDodgen — May 29, 2008 @ 11:44 am
May 29th, 2008 at 12:12 pm
Thanks, Mike. Excellent post. I had a joke in mind, but, unfortunately, Todd beat me to the punch.
I think an important take away is that these tendencies exist, but can be overcome, at least in particular instances. Some of us, if not all, have had experiences where our viewpoints have shifted 180 degrees after looking at further arguments and evidence. I suspect it is easier to make that shift if one does not have a stong previous commitment - professionally, personally, politically. However, I am heartened that 'shift happens,' even in some difficult cases, as Gil notes.
The exciting challenge then is twofold: to be able to detect disconfirmation bias in others, and, perhaps more importantly, to make a valiant (and, no doubt, lifelong) attempt to detect it and hopefully correct it in oneself.
Comment by Eric Anderson — May 29, 2008 @ 12:12 pm
May 29th, 2008 at 12:36 pm
A Bayesian analysis of converging and diverging views:
http://omega.albany.edu:8008/E...
Comment by Raevmo — May 29, 2008 @ 12:36 pm
May 29th, 2008 at 3:36 pm
Speaking of "dis-/confirmation bias," an additional two choices were offered (by me) in the same thread Mike Gene refers to, but attracted little notice.
Comment by Rock — May 29, 2008 @ 3:36 pm
May 29th, 2008 at 4:27 pm
Rock,
I read the abstract of the paper you cited in that thread. You lost me, pal.
Raevmo,
This computer didn't know how to open your link.
Put me in that group.
Comment by Bilbo — May 29, 2008 @ 4:27 pm
May 29th, 2008 at 4:32 pm
Bilbo:
It links to a postscript file. For free software to process ps files:
http://www.ghostscript.com/awk...
Comment by Raevmo — May 29, 2008 @ 4:32 pm
May 29th, 2008 at 5:01 pm
Raevmo,
It's taking longer to download the file than I have left at the library. I'll try again later.
Comment by Bilbo — May 29, 2008 @ 5:01 pm
May 29th, 2008 at 10:19 pm
Hi Eric,
I have suggested ways: I propose that you can detect disconfirmation bias at work, in individuals or groups, when hyper-skepticism, stereotype, misrepresentation, faulty extrapolations, and personal attacks occur more often than not. I have found these to be very helpful signposts.
It also helps to remember that disconfirmation bias may often be associated with naïve realism, as I have outlined earlier.
Yes, and this is another place where The Design Matrix comes in. By laying one's scores on the table, and then defending the score relative to another's score, it will be easier to for a person to determine if confirmation/disconfirmation bias is in play.
For example, if someone tried to give the bacterial flagellum a deeply negative Analogy score, it would be pretty clear that disconfirmation bias is in play.
Comment by MikeGene — May 29, 2008 @ 10:19 pm
May 29th, 2008 at 10:35 pm
Hi Mike,
Thanks for posting about this. In my opinion this is a very important topic.
http://www.psychsystems.net/la...
This is a link to a study showing that staunch Republicans and staunch Democrats are not rational — IE, they are not deciding on the "weight" or "ratio" of the evidence for or against their positions.
Studies of this nature strongly support my long held view that it does no good whatsoever to replace religious fundamentalism with atheist fundamentalism. In nether case are the rational/reasoning portions of the human brain being used. The problem is the emotive "staunchness" or "fundamentalism." Militant atheists who go on crusades against religion are completely missing the point IMO.
Comment by William Brookfield — May 29, 2008 @ 10:35 pm
May 30th, 2008 at 9:50 am
There's bias and then there's bias. Not all bias is negative, and can, in some circumstances, provide clarity and focus. For example, I'm a theist. More specifically I am a Christian with a strong "bias" to the Judeo-Christian tradition. Naturally, I read and listen to all arguments for naturalism and/or atheism through my "bias". My bias helps me analyze these arguments with more clarity because I have a strong baseline from which to measure. My biased baseline includes things like logical consistency, strict adherence to the rules of logic and the first principles of reasoning, clarity of terms, and so forth, because the strength of those things are what confirms my acceptance of the truth of the Judeo-Christian worldview.
Could my worldview be changed? Sure. If I were to be presented with arguments that didn't violate these principles, which I take to be the result of my bias, and those arguments pointed to a contrary worldview, and met the criteria my bias demands, then, yes, I'd be open to change my worldview. Thus far in my life, I've not encountered such a case. Not because my bias prevents me from seeing discomfirmation, but because my bias provides guidance and clarity as to what I need to be looking for and where the baseline is.
If we didn't have such baselines in our reasoning, then how would we ever know if we encountered a contrary argument to our beliefs or biases? Indeed, the only way I can see that any argument could be labled as "disconfirming" is to have a fairly well established baseline from which to make the determination.
All of that to say that I don't necessarily take "discomfirmation bias" as being necessarily negative, blinding to truth, or anything of the sort.
Comment by DonaldM — May 30, 2008 @ 9:50 am
May 31st, 2008 at 2:00 pm
I read the abstract of the paper you cited in that thread. You lost me, pal."”Bilbo
Sorry, Bilbo. But the fact that I "lost you," may indicate something even more fundamental than a "disconfirmation bias" at work. Some things just "don't compute" and therefore cannot be said to enter a "dis-/confirmation bias." I've seen this a lot in these discussions. I've said that the IDers and their critics have this whole "cosa nostra" thing going on. Every subject introduced must ultimately be reducible to the shared constructs of their own pre-conceptions. I.e., these arguments revolved around a shared set of presumptions (not often made explicit), terms and concepts and little effort is made to "push the envelope."
You've formed your own "mutual debating society" (a Cosa Nostra) that works by your own tacitly accepted rules, in your own tacitly accepted terms and concepts, and which must be conducted according to those rules, terms, and concepts only.
No "thinking outside the box."
Anyway, I haven't read Mike Gene's book but it includes some sort of subjective dis-/continuity evaluation. Seems intuitive enough. Designers exercise effective control over natural forces, acting to alter the course of natural events to obtain outcomes that would not otherwise obtain. Designers create continuities and discontinuities.
A significant discontinuity in the evolutionary history of life on Earth occurred when the very products of that evolutionary process (humans e.g.) began to knowingly, consciously, deliberately, intelligently, and with purpose, planning, and foresight, act to effective control those processes, alter the course of natural events. (And that is science applied.)
Specifically, the subject of the review I linked.
Here we have a comparative test case: Known "Intelligent Designer," with known purposes, and using known methods. With an established (evolution + design) theory in hand and using standard tools of analysis is it possible to reconstruct the domestication of plants and animals by humans? Can we detect design in this case? Can we localize "domestication events" in time and space? Can we identify a "domestication syndrome," a suite of traits deliberately modified by the actions of the domesticators? Is there a reliably identifiable set of related phenomena indicative of such actions (e.g., sympatric speciation associated with a truncated selection regime)? Etc.
My "disconfirmation bias" began to kick in as I began to adumbrate in my own mind some of genetic phenomena involved. I thought that either singly or in combination, or even all the ones mentioned occurring altogether at the same time and place with independent corroboration (archaeological, e.g.), making a distinction between the outcomes attributable to natural evolutionary processes and those deliberately controlled to effect different outcomes would still be a considerable challenge and may indeed have not wholly satisfactory results.
This tends to support Mike Gene's assertion that science is unequipped to handle design. I disagree. (Always have, with the IDers and their critics on this one.) But its an entirely different issue the Cosa Nostra is debating, isn't it? It's not really about "design."
Evolutionary theory and natural science in general is so equipped, but the results of using that equipment may involve ponderable ambiguities, uncertainties, etc. That even when the designers are known, their purposes are known, and their methods are known, there are considerable difficulties and subtleties in making such inferences (or "detecting design") unambiguously in any case or reliably over all.
Biases are an effective but risky strategy. The biases at work in these discussions may have no functional utility or effectiveness whatsoever, which may be one explanation why the scientific community ignores this "debate."
But just hoiw risky are your biases, etc. Would you risk everything?
Comment by Rock — May 31, 2008 @ 2:00 pm
May 31st, 2008 at 3:12 pm
Well said Rock. Discontinuities are recognizable by knowledge of what- continuity? How does one distinguish between discontinuity and emergence or do we?
Comment by Bradford — May 31, 2008 @ 3:12 pm
June 2nd, 2008 at 7:52 pm
Okay Rock,
Your rant made me read a little more of the article you sight:
Okay, now I understand the relevance to ID. From your rant, I'm guessing that there is debate about when certain crops were domesticated, which means there is debate about when ID took place, even when we know that there was a designer. Fair enough. We debate about many things, whether or not ID took place. I sincerely believe that 9/11 involved far more than Al-Qaeda, and that the Bush administration and the Pentagon played a large role in making sure it happened. But I doubt that you would accept that (or most of the people here). We debate whether Oswald acted alone, or was part of a larger conspiracy (again, I think the latter).
So there is debate about ID in many areas. It doesn't surprise me that it occurs in the question of crop domestication. But there are some of us who wonder whether if ID took place in the origin and evolution of life, also. If confining our discussion to those issues bothers you, and you think we've formed some sort of "Cosa Nostra," so be it. If the question of when ID took place in crop domestication sheds some light on the question of if and when ID took place in the origin and evolution of life, great. If it doesn't, then yes, I would find it irrelevant. If your argument is the following:
"We can't even determine when ID took place in crop domestication, so what makes us think we could ever determine if it took place in the origin and evolution of life?"
Then your argument may be good, or may not. Is it possible that the evidence for crop domestication is more subtle, less easily identifiable than for the origin and evolution of life? If you think the answer is no, then write an essay, and we'll post it as a guest thread in "Cosa Nostra." I always thought you were part of our family, anyway, Rock.
Comment by Bilbo — June 2, 2008 @ 7:52 pm
June 3rd, 2008 at 4:26 pm
Sorry for bringing up my paranoid, political views. Obviously I'm a wacko who has his design-detection device turned up way too high, in order to support his own confirmation biases.:wink:
Comment by Bilbo — June 3, 2008 @ 4:26 pm