Monday, January 28, 2013

change blindness

Change blindness is the failure to detect non-trivial changes in the visual field. The failure to see things changing right before your eyes may seem like a design fault, but it is actually a sign of evolutionary efficiency.

Examples may be seen by clicking  here, here, here, here, and here.

The term 'change blindness' was introduced by Ronald Rensink in 1997, although research in this area had been going on for many years. Experiments have shown that dramatic changes in the visual field often go unnoticed whether they are brought in gradually, flickered in and out, or abruptly brought in and out at various time intervals. The implication seems to be that the brain requires few details for our visual representations; the brain doesn't store dozens of details to which it can compare changes (Simons and Levin: 1998). The brain is not a video recorder and it is not constantly processing all the sense data available to it but is inattentive to much of that data, at least on a conscious level.

Monday, January 21, 2013

bias blind spot

The bias blind spot was described by Princeton University psychologist Emily Pronin and her colleagues (2002) as the tendency to perceive cognitive and motivational biases much more in others than in oneself. The bias blind spot is a metabias since it refers to a pattern of inaccurate judgment in reasoning about cognitive biases.

Monday, January 14, 2013

suppressed evidence

A cogent argument presents all the relevant evidence. An argument that omits relevant evidence appears stronger and more cogent than it is.

The fallacy of suppressed evidence occurs when an arguer intentionally omits relevant data. This is a difficult fallacy to detect because we often have no way of knowing that we haven't been told the whole truth.

Many advertisements commit this fallacy. Ads inform us of a product's dangers only if required to do so by law. Ads never state that a competitor's product is equally good. The coal [*], asbestos [*], nuclear [*], and tobacco [*] industries have knowingly suppressed evidence regarding the health of their employees or the health hazards of their industries and products.

Monday, January 7, 2013

anecdotal evidence (testimonials)

Testimonials and anecdotes are used to support claims in many fields. Advertisers often rely on testimonials to persuade consumers of the effectiveness or value of their products or services. Others use anecdotes to drive home the horror of some alleged activity or the danger of widely-used electronic devices like cell phones. In the mid-90s, there were many people, some in law enforcement, claiming that Satanists were abducting and abusing children on a massive scale. The anecdotes involved vivid descriptions of horrible sexual abuse, even murder of innocent children. The anecdotes were quite convincing, especially when they were repeated on nationally televised programs with popular hosts like Geraldo Rivera. A four-year study in the early 1990s found the allegations of satanic ritual abuse to be without merit. Researchers investigated more than 12,000 accusations and surveyed more than 11,000 psychiatric, social service, and law enforcement personnel. The researchers could find no unequivocal evidence for a single case of satanic cult ritual abuse.