Thursday, June 17, 2010

Applied Research: The Worked Example

It is hard to find any empirically tested media tropes, but here is one: the worked-example effect, predicted by cognitive load theory (Sweller, 1988). According to him, this is the best known and most widely studied of the cognitive load effects.

"A worked example is a step-by-step demonstration of how to perform a task or how to solve a problem” (Clark, Nguyen, Sweller, 2006, p. 190). Studying worked examples is an effective instructional strategy to teach complex problem-solving skills (van MerriĆ«nboer, 1997). This is because example-based instruction provides expert mental models, to explain the steps of a solution for novices.

Researchers Sweller and Cooper looked first at the teaching of algebra. Early on, they saw that merely showing worked problems was not any better, learning-wise, than merely having students solve problems on their own. With sufficient structuring, however, which reduces cognitive load, the method appeared to work better than unaided solutions.  Importantly, for media designers, they found that (paper) display of both  text and diagrams reduced cogntive load, as we covered in an earlier post (Split-attention effect). Sweller later proposed applications for animation, (closer to home for us).

Not for beginners
The folks this strategy works best for are the more experienced students, and just a little "worked" material seems to be sufficient, follwed by multiple experiences of unaided solving. All of this is related to a more general body of thought, coming out of Dewey, Piaget, Montessori, Vygotsky, and others, called Problem-based learning (PBL) where students collaboratively solve problems and discuss their experiences as they go, or immediately following the exercise.This is not a matter of dumping the non-swimmers into the deep end. PBL assumes some earlier, didactic training in various problem solving strategies and heuristic reasoning first. In this view, the teacher's role quickly shifts however, after providing sufficient theorectical and procedural structure, to that of a facilitator of active collaboration by students facing a challenging, practical problem. The payoff is solving in context, with the complexity of the real-world reflected in the process as well as the outcome.

This techniqie has been applied extensively in professional training for physicians and engineers, and is one I'm entertaining for the training of non-profit professionals in recruiting, fund-raising and enrollment tasks.

Most of the citations I've found are in classroom or lab settings. Applying the technique to video and online will take some imagination. Clearly, the media will have to model a process as well as introduce specific "challenge" materials to be solved.


No comments: