Assistance Hypothesis

The Assistance Hypothesis is: Robust learning will be enhanced by providing assistance in inverse proportion to how well a student knows a component of knowledge.

That is, for beginning learners, high assistance instruction is more efficient than low assistance instruction, and for advanced learners, low assistance instruction is more efficient than high assistance instruction. This hypothesis is familiar to teachers, and it is often associated with Vygotsky's (1978) zone of proximal develoment and the Collins et al. (1989) motto: model, scaffold, fade. Woods, Bruner and Ross (1976) coined the term “scaffolding” for assistance that is eventually removed (faded), but the term “scaffolding” is often mystifying to those outside the Learning Sciences, so we prefer “assistance.” Some examples follow.

Example 1

Suppose students are studying an example of a multi-step problem, which consists of a sequence of steps (e.g., lines of a geometry proof; equations in a physics problem’s solution) each of which is derived from earlier steps by some domain principle. We assume the steps themselves are presented to the student. The instructional design issue is how to get students to attend to each step’s justification. A high-assistance alternative is to play a recorded spoken explanation of the step as each step is displayed. A moderate-assistance alternative is to have students justify each step by selecting an explanation from a menu, with feedback on incorrect selections. A low-assistance alternative is to train students to self-explain, then let them study an ordinary printed example. If the experiment has students study a sequence of 10 examples, and all of the students rank as beginners when they start, then the most efficient instruction should be to use recorded spoken explanations for the first few examples; menus with feedback for the next few examples, and self-explanation for the remaining examples.

Example 2

When learning second language vocabulary, one issue is how closely to space trials on the same word pair. For instance, how many other word pairs should occur between two occurrences of hat-chapeau? A high assistance alternative is to closely space the two occurrences, because this makes it easier to get the second one correct. A low-assistance alternative is to space the two occurrences far apart, since this makes recall more difficult. Similarly, learners can be ranked by their recent successes. Given these two rankings, efficiency should be maximized by an adaptive spacing policy, which increases the spacing slowly as the learners competence increases.

These examples illustrate the Assistance Hypothesis, that efficiency improves when instructional assistance is inversely matched to the learners’ progress. The examples also suggest that there may be different mechanisms--motivational, cognitive and practical--that underlie different specific applications of the assistance hypothesis. This illustrates why we need both a macro level and a micro level.

References

• Collins, A., Brown, J. S., & Newman, S. E. (1989). Cognitive apprenticeship: Teaching the craft of reading, writing and mathematics. In L. B. Resnick (Ed.), Knowing, learning and instruction: Essays in honor of Robert Glaser (pp. 453-494). Hillsdale, NJ: Lawrence Erlbaum Associates.

• Vygotsky, L. S. (1978). Mind in Society: The Development of Higher Psychological Processes. Cambridge, MA: Harvard University Press.

• Wood, D. J., Bruner, J. S., & Ross, G. (1976). The role of tutoring in problem solving. Journal of Child Psychology and Psychiatry, 17, 89-100.