Thursday, July 21, 2005

Problem Detection.

I read a great paper from Gary Klein in Cognition, Technology and Work on problem detection. The great thing about the paper is that even though I had not thought about much of what he discusses, everything he says can be explained by my cognition model. I love it when that happens.

Here is the essence. Traditional problem detection is modeled as an accumulation of evidence that things are not as they should be. When it reaches a threshold, a problem is detected. Gary says that this is just one case. Instead, problem detection should be modeling as a general sense-making process. We are always trying to maintain situation awareness. Problem detection is basically a shift from one schema to another to explain the current situation. There are many ways that this shift develops.

The Recognition Primed Decision making model contradicts the traditional evaluation of alternatives model of decision because we don't activate multiple schemas and compare them. Instead, the evidence activates cell assemblies until a schema that matches this pattern reaches threshold.

From a problem detection point of view, we start out with this situation schema activated. Contradictory evidence can be experienced and handled in several ways. In the traditional special case, small pieces of contradictory evidence can be modeled as cell assemblies with inhibitory connections with the active schema. If this inhibition accumulates, it can activate the mismatch schema and cause the person to reconsider the situation. The problem with this is that we have a strong tendency to explain away, or even ignore, contradictory evidence. So unless a huge amount of contradictory evidence is experienced, the reconsideration may never happen.

Another way that problems can be identified is the detection of one large contradictory symptom. This activates a strong inhibitory link to the schema and activates the mismatch all at once. This is more likely because it is harder to explain away the strong contradiction.

A third way that problems can be identified is the detection of a small contradictory symptom that the person chooses to believe and investigate. This can happen because of what Gary calls stance. He defines stance as the emotional state that the person starts out with. If someone is generally suspicious or has external incentives to identify problems, the mismatch schema may start out primed. This facilitates the activation of the mismatch schema from less contradictory evidence.

One final point that I want to discuss is his contention that when a person repeatedly explains away anomalies, he/she is less likely to recognize future contradictory evidence. What is happening here is that the mismatch schema is being inhibited itself. This can also occur based on stance (a generally accepting personality, external incentives to maintain the status quo, fear of ones own inexperience, etc.). If the mismatch schema is inhibited, it cannot reach threshold unless something very strongly contradictory is detected.

For any of these cases, even when there is a gradual activation of small inhibitory links, it is not a conscious process. At one point in time, the pattern recognition process has activated one schema. At some point, another schema becomes activated, thus inhibiting the original. It is a binary shift from one to the other.

There is a lot more of interest in the paper. I recommend reading it.

Klein G., Pliske R. and Crandall B. (2005). Problem detection. Cognition, Technology, and Work, 7, 14-28.