Wednesday, September 19, 2012

What is confirmation bias?

Confirmation bias is a a form of cognitive bias,which often manifests as an inability or unwillingness to spot faults in arguments with which we agree.

One of the classic examples of confirmation bias is the tendency to cherry-pick evidence. It has been repeatedly shown in experiments that people generally test hypotheses in a very one-sided way, by deliberately searching for evidence consistent with the hypotheses they find agreeable and neglecting evidence that conflicts with their worldview.

Another classic example is the persistence of discredited belief. Take the neoliberal theory of "trickle-down economics" as an example. Neoliberals argued that a minority of people should be allowed to develop extreme wealth so that the wealth would then trickle down to wider society. The economic evidence is absolutely clear that this effect never happened and that in fact the opposite is true; that allowing a minority to develop extreme wealth, massively widens the gap between the rich and the ordinary (because the wealthy elite often just hire tax lawyers to ensure that their wealth ends up stashed in personal accounts in tax-havens rather than allowing it to "trickle away" to wider society). Despite the wealth of concrete evidence that the trickle down effect is a myth, many people still believe in it because it suits their worldview and provides them with (pseudo) economic justification for their greed.

Everyone suffers from confirmation bias to a certain extent. It is always easier to spot errors in statements we find disagreeable than it is to find errors in statements we like.

"That seems wrong; in what way is it wrong?" is a perfectly natural though process, however on the face of it "that seems right, how is it wrong?" seems like an absurd though process. I believe that the fact that humanity has been able to recognise and develop the second state has been one of the key driving forces in human advancement. To give a crude example; the scientist that tends to critically appraise the commonly accepted model (that seems right, how is it wrong?) is far more likely to end up devising a groundbreaking and superior new model than the scientist that instinctively prefers models that form part of the established paradigm, and reserves their criticism for unorthodox ideas (That seems wrong; in what way is it wrong?).

It shouldn't matter whether we agree with a hypothesis or not; from an unbiased and objective point of view, the most important thing to consider should be whether the subject matter is rational and coherent. Is it backed by facts, logic, reason, empirical evidence? Or by simplistic generalisations, anecdotal evidence, unsubstantiated opinion, fallacious argument strategies?

In order to adopt a more rational, objective stance it is particularly important to strive to find errors in statements with which one generally agrees, since the mind tends to instinctively deconstruct disagreeable statements and blithely accept agreeable ones. In order to overcome confirmation bias and maintain objectivity one must actively strive to critique agreeable subject matter in a similar way to which we naturally tend to critique the disagreeable. If we give in to the natural tendency to subject disagreeable subject matter to much greater levels of scrutiny, we allow ourselves to create an increasingly subjective worldview.

Politicians and the media thrive on this human tendency to form subjective worldviews by providing a steady supply of simplistic justification narratives for their favoured policies. As long as they can get the basic narrative right, it doesn't really matter how much empirical evidence they go on to provide, since huge numbers of people will blithely accept an agreeable narrative because of confirmation bias.

To give an example: People generally don't like unfairness, so they find the idea that they must work hard whilst others laze around "scrounging off the state" acutely disagreeable.  In the UK the Tories and the right-wing press play up to this sentiment by grotesquely exaggerating the number of "benefits scroungers" any downplaying (or completely ignoring) the fact that their own favoured austerity policies have actually increased unemployment and under-employment by reducing the amount of demand in the economy. Once the "scroungers narrative" is set, it is almost impossible to make a reasoned counter-argument, since confirmation bias will allow those that find the "scroungers narrative" plausible, to blithely dismiss any facts and evidence as leftie "scrounger apologism"; thus the "blame the victim fallacy" becomes another example of the the persistence of discredited belief.

Once we realise that swathes of political debate and media commentary are fundamentally reliant on simplistic justification narratives, the confirmation bias effect and the subjective worldviews of the general public, it becomes extremely important to recognise that  the "agreeability" of political statements or media representations should be secondary considerations to their validity.

In the practical reality of day-to-day existence the maintenance of such a deliberately considered and objective stance is impossible. We cannot rationally deconstruct every statement we ever hear in search of methodological flaws so we often rely on heuristic judgements (rule of thumb, common sense, educated guesses, believing in testimony of previously reliable witness, personal opinion). I mean who would even want to brutally deconstruct their favourite piece of poetry,  cherished work of art, sentimental object or the words "I love you" in search of empirical validity?

It is extremely important to realise is when we are allowing ourselves to apply heuristic short-cuts and when we must apply rigorous objective analysis to avoid being misled. When a friend invites us around for dinner at 7.00 PM there is absolutely no need to subject their statement to rigorous critical appraisal, however whenever we read a newspaper article, listen to a politician speaking on the radio or watch an advert on the TV, it is much more important to apply critical analysis, even if we tend to agree with what is being said.

In order to maintain a more objective view of reality it is vitally important to read between the lines because what is omitted is often far more important that what is presented by the media as "objective fact"; to critically doubt everything that comes out of a politician's mouth, even if you find yourself instinctively agreeing with them at the time; or to carefully consider the tricks and techniques being used by the advertiser to incentivise us to pay for their products even if we instinctively want to buy them.

The more effort we expend on combating confirmation bias, the more natural it becomes to us,  however it will always be impossible to live ones entire life on a unbiased plain of perfect rationality and objectivity. This means that it is important to recognise when it is necessary to deliberately adopt a more objective and critical stance and also to be aware that we will continue to live most of our lives in a much more comfortable cloud of subjectivity, unsubstantiated opinion and heuristics.

We must recognise when we are allowing ourselves to adopt such a heuristic state, since a great deal of propaganda can slip through as we relax, peruse a seemingly lightweight magazine, read a crappy novel or watch a soap opera. "Soft media" is actually an ideal medium for propagating social stereotypes, facile generalisations, fallacious arguments and the like, precisely because most people choose to read a celebrity magazine or watch a soap opera as an escape from the hard world of critical analysis. Once we are in this relaxed, uncritical, heuristic state lazing around in front of the TV or comfort reading we are much less likely to subject the subject matter to painstaking objective analysis, meaning confirmation bias is more likely to allow subjective and distorted ideas to leak into our consciousness.

As a crudely oversimplified conclusion, I suppose I could say that: As we observe a subject matter, the first step towards avoiding confirmation bias, and the subjective distortions it creates, is to try to be aware of our own state as we are making the observation.

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