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Paper now available. Published in Applied Ergonomics

Supporting productive thinking.

Quantifying the Limits of Human Information Processing

Early discoveries related to the information processing capacity of human's were welcomed by Applied Cognitive Psychologists, because for the first time they could provide their engineering colleagues with precise numbers. For example, the Hick-Hyman Law and Fitts' Law allowed quantitative estimates of the bandwidth of the human information processing channel (approximately 7-10 bits/sec); and G.A. Miller's famous paper provided a quantitative estimate of the capacity of working memory of from 5 to 9 chunks.

Thus, when the engineers asked how much information to put into a display - the psychologists could provide a number - probably not more than 7 or 9 chunks. However, the smart engineers (and the smart psychologists) were not very satisfied with this estimate. They realized that the numbers were meaningless unless it was possible to specify what constituted a chunk with respect to the domain being represented.

The Power of Chunking

If you read G.A. Miller's paper thoroughly, you will discover that the ultimate conclusion is that, due to the power of chunking, there seems to be no practical limit to the capacity of working memory. Miller describes how a colleague was capable of remembering long strings of binary digits, by using various strategies for recoding them into chunks.

It is a bit dramatic to watch a person get 40 binary digits in a row and then repeat them back without error. However, if you think of this merely as a mnemonic trick for extending the memory span, you will miss the more important point that is implicit in nearly all such mnemonic devices. The point is that recoding is an extremely powerful weapon for increasing the amount of information that we can deal with. In one form or another we use recoding constantly in our daily behavior. (Miller, 1956, p. 95

In this example, the stimulus (strings of binary digits) had no intrinsic structure - so the chunking strategies used were essentially mnemonic tricks (e.g., using an octal coding). That is, the chunking structure is imposed by the observer as an alternative internal representation.

Building on de Groot's observations of chess, Chase and Simon illustrated the power of chunking in relation to expertise. Their research showed that Expert Chess players had superior ability to recall positions after a very brief exposure to a chess game, than more junior players. While the recall of junior players seemed to be in the range of 7 or so pieces, experts could often reproduce the entire game. However, these differences in recall between expert and junior players were essentially eliminated when the recall task involved pieces randomly positioned on the chess board.

It appears that the 'chunking' ability that allowed the superior recall of the experts was dependent on preserving the structure of the game of chess. When the constraints of the game were eliminated, the recall advantage disappeared. This suggests that chunking structure was not an arbitrary mnemonic structure, but rather it was dependent on the intrinsic structure of chess (e.g., the rules of the game, the intentions of the players, the strength or weaknesses of positions relative to winning the game).

Chunking, Attunement, & Coordinative Structure

Perhaps, chunking facilitates memory and problem solving in a fashion analogously to how coordinative structures facilitate motor control. The superior memory capability and the ability of expert chess players to see a good option quickly suggest that they are tuned to the functional constraints of the game of chess, in the same way that a specific coordinative structure might be tuned to accomplish a specific motor function (e.g., see discussion of golf shots in previous post on requisite variety).

With regards to the discussion of requisite variety in an earlier post, the tuning to the functional constraints of the game would tend to make the signals more salient (e.g., the strengths/weaknesses of various positions) and reduce the noise (i.e., possibilities inconsistent with the constraints of the game). When the functional constraints of the game of chess are removed - the advantages of this tuning disappear.

In a similar way, Gibson's ecological optics and the related notion of optical invariance, can also be seen as an ecological basis for chunking. In other words, the optical structure provides a means for tuning into the natural constraints (or natural dimensionality) associated with control of locomotion - making the relative signals salient (allowing direct perception).

This also has clear implications for designing graphical interfaces - as emphasized in Ecological Interface Design. The key is to design representations (e.g., analogs or metaphors) that make the structure or constraints of a process salient. Thus, helping people to tune into meaningful chunks or dimensions with respect to the process control problem. The key challenge then, is to discover the natural structure intrinsic to the process being controlled (e.g., the constraints, laws or invariants). This is the ultimate goal of work analysis (e.g, Vicente (1999).

Chunking to highlight the deep structure of a problem

A key point here is to get beyond the numbers (7 + or - 2) and to get beyond the idea that chunking is a simple mnemonic trick in order to appreciate that it is possible to parse problems into functionally meaningful chunks. This is illustrated by Wertheimer's (1959) concept of productive thinking. He shows that productive thinking depends on representations that parse a problem in terms of its deep structure. The key point is that the practical power of chunking comes when an observer is tuned to and uses the natural structure of the problem (e.g., constraints, patterns, invariants, categories)  in productive ways. 

 

 

 

25

Pirsig's Metaphysics of Quality

In his second book Lila, Pirsig tells an anecdote about a Native American Indian who responds to a question about the type of a particular dog with the answer "That's a good dog." The questioner laughs at this response, as if the question was not understood. But Pirsig notes that for Native American's "good" is a quality of the dog that can be directly experienced. That is, "good" is not a subjective interpretation, an opinion of the observer, but an ontologically basic property of the experience. In other words, "good" is a property that can be directly perceived.

This is an aspect of the dynamics of circles that is not well appreciated - in addition to affording and specifying - satisfying is fundamental to the dynamics of abduction or adaptive control.

In the classical Western view, properties such as 'goodness' are subjective or derivative. As such, they fall outside of the sphere of science and are relegated to the arts. In pursuit of objectivity, Western science has defined all questions associated with value as irrelevant or extrinsic to its mission to understand reality. The implication is that value is not real. It is not an ontological primitive. It is a derivative property that is open to interpretation.

However, the stability of a system that is intimately coupled with an ecology depends critically on the ability to discriminate between the 'good' (e.g., nutritious, safe, growth enhancing) and the 'bad' (e.g., poisonous, threatening, stifling). Thus, the implication of Pirsig's Metaphysics of Quality is that for the dynamics of experience - qualities such as good and bad are ontologically basic. Much more so than the objective properties of Western Science (e.g., position, velocity, size, weight).

The objective properties of Western Science were specifically chosen to describe a reality that was independent from an observer. However, a science of experience is interested specifically in the properties that relate to stability of the coupling between perception and action (or the coupling between the actor and the ecology). These properties include constraints on action (affording), constraints on perception (specifying), and constraints on value (satisfying). Each specified as duals that depend jointly on properties of the relations between actor and ecology.

It is the constraints on value (satisfying) that determine the attractive potential of the field of experience -- whereas the constraints on action and perception will determine what attractors can be realized and what repellers can be avoided.  In other words, the constraints on value determine the relations between the ecology and the health of the actor (e.g., consequences). And the constraints on information and action determine the capacity of the actor to discriminate and control action to realize the healthy consequences  and avoid the dangerous consequences.

The key point of the Metaphysics of Quality is that the constraints on value (i.e., what is good and bad; healthy or dangerous) are as ontologically basic to experience as the constraints on action and information.  These three types of constraint jointly shape motion through the field of experience.

In relation to the previous post - emotions may be that aspect of experience that reflects attunement to properties associated with value. Falling in love is an example of detecting an attractor. For example, we fall in love with an object (e.g., a house, a car, another person) and then the constraints on perception and action determine whether the object can be obtained or not. A person without emotions is like a boat without a destination - adrift on the seas, fully functional (i.e., controllable) but with no reference for preferring one direction to another.

4

Emotions and Rationality

Conventionally, emotion has been seen as a threat to rationality - where an emotional choice is treated as if it is the opposite of a rational choice. When Descartes split the mind from the body - emotion was linked with the body - not with the mind. Emotions tended to be seen as vestiges of a more primitive brain that had been superseded by the more rational/logical neocortex. To be rational, meant to suppress the emotional urges in favor of more deliberative logic.

However, researchers such as Antonio Damasio are discovering  that emotions may be integral to effective decision making and problem solving. In essence the emotions help to ground rationality with respect to the practical value of decisions. Emotions tend to "mark" choices that have high negative or positive value. In this way, the emotions are integral to the process of learning from past mistakes and past successes.

Emotions may also be important in terms of the persistence needed to overcome obstacles to success - particularly when it comes to innovation. Feyerabend suggests that without passion, many innovations in science would have been overwhelmed by the logic of the conventional ways of thinking. The weight of evidence/logic always favors the conventional paradigms -- and it takes time for enough evidence to accumulate to drive a paradigm shift.  Thus, success of the new paradigm often depends on the passion to persist against the weight of the conventional perspective.

Also, emotions may help to set 'stopping rules' for analytical thinking.  For example, Damasio found that patients with damage impacting the coupling of emotional to logical brain centers can be subject to a paralysis of analysis, where they get caught in analytical deliberations that seem to go on without end - there is always another angle to consider or another piece of data to collect.  Thus, emotions may play an important role in triggering actions, particularly in complex situations, where certainty is not possible. In complex environments (e.g., military command and control, medicine), it is rarely possible to reach certainty. At some point, a commander or physician must act before they are overtaken by events or before windows of opportunity close.  In these situations, decisive action may be more important that having a perfect plan.

Carl Weick illustrates this with his story about the squad lost in the Alps, who are saved when they discover that they have a map. It later turns out that it was the wrong map. The key is that having the map helped to trigger actions - and that the actions eventually led to successful adaptations. One of the positive aspects of decision heuristics such as those suggested by Gigerenzer is that they tend to be recipes for action. In contrast to normative logic or economic models of rationality, the trigger for action (stopping rule) is often integral to the heuristics.

The point is that decisive action may be critical to success. Rather than waiting to make the right decision, success often depends on acting to make the decision right. Emotional intelligence, rather than logic may be critical in triggering the necessary actions.

The Gordian Knot

The story of Alexander the Great and the Gordian Knot may be an illustration of the idea of acting to make the decision right.  While others debated how best to untie the knot, Alexander acted decisively to solve the problem.

Perhaps, this is one facet of the attractiveness of Trump and his ultimate success in the 2016 election. While the conventional Democrats and Republicans debated over the best way to untie the complex knots that our country was facing, Trump drew his sword and promised action. Thus, Trump's logic was seen as more grounded in terms of action. Whereas, the logic of the conventional political establishment seemed to be caught in a paralysis of analysis - debating how to untie the knot, rather than acting to make things right. 

Perhaps many in America were fed up with the logical analysis provided by the media and the conventional politicians. They were looking for action (high energy). They were less interested in whether the logic guiding the action was sound, they were simply tired of analysis and were impatient for action.

Now the ultimate question is not whether Trump's solutions make sense (are they logical)? The only question is will they work? Will Trump's sword cut? If it cuts, no one will be concerned with the logic of how to untie the knots. The ultimate test of a leader is not logical, but pragmatic. Do they get the job done?

Perhaps, the failure of conventional politics is not in the logic of right wing versus left wing. Progress does not depend on who is more logical. It depends on who has the courage to act. Perhaps, the failure of conventional politics today is too much analysis and too little action.

The point is not to to encourage rash action, but to realize that in a complex world there is no certainty without action. No matter how carefully you aim, no target can be hit unless you pull the trigger. And if it's a moving target, you can't take too much time aiming or you miss the opportunity.

Perhaps, in the end it is not about making the right choice, but rather it is about acting to making the choice right.