RECURSION VS ITERATION - AN EMPIRICAL-STUDY OF COMPREHENSION

An extensive study involving three test groups over a period of three different years was performed to determine differences between compreh ension of recursive and iterative code constructs. This study involved computer science students enrolled in six different data structure cl asses using PASCAL and obtained 275 responses, which were statisticall y analyzed. Using a chi(2) test, one task - searching a linked list fo r a given value - showed a statistically significant (p = 0.006) diffe rence in comprehension favoring recursion. Another task - making a cop y of a linked list - favored iteration, but not with statistical signi ficance. Among responses with correct comprehension, a comparison of m eans test was performed on the comprehension times among the latter tw o groups in the study. There was a faster rate of comprehension of the recursive code for both of the tasks (p = 0.096 for the search and p = 0.045 for the copy). A two-way analysis of variance suggested a tend ency toward an interaction effect between task and construct in terms of comprehension time.