Surface/Deep Catagories

One of the most cited pieces of cognitive science research on the a differences between experts and novices was done in 1981 Micki Chi of the University of Pittsburgh. Chi studied how expert and novice physicists sorted a set of index cards, each containing a standard end-of-chapter physics problem. Instead of solving them, Chi asked the two groups of subjects to sort them based on whatever system of categories they devised.

Chi found that novices sorted problems based on their surface features, while experts sorted their cards based on the underlying principle needed to solve the problem. For instance, a novice might put two problems involving an object moving down a slope together, stating that they both involved planes. On the other hand, the expert, when grouping the same cards, put together those that at first glance were quite dissimilar -- such as on problem on inclined planes and another with a weight on a spring that is moving back and forth. The experts explained that the idea of conservation of energy linked the two dissimilar-looking problems. Novices did not understand physics well enough to see this connection, and were instead drawn towards the problems surface context more.