Data Flow Metrics in Program Comprehension Tasks

Existing research in program comprehension has paid less attention to the coverage of programming concepts that were contained within the source codes used for studies. In this paper, we examine source codes covering four introductory programming concepts: branching, loops and arrays, sorting, and tail recursion. The diverse types of code fragments give rise to eye movement patterns more structured according to the control flow and data flow of the program. To facilitate analysis of this class of program comprehension strategies, we propose data flow-based metrics and describe automatic computation of the metrics. In evaluation of the proposal, we conducted a pilot study with novice and intermediate programmers. In the study with recordings from 26 programmers we compute basic fixation and saccade metrics along with a data flow-based metric.