Ability to 'explain in plain english' linked to proficiency in computer-based programming

This study investigates the relationship between novice programmers' ability to explain code segments and their ability to write code. Results show a strong correlation between ability to correctly answer 'explain in plain English' (EiPE) questions and ability to write code indicating that there are aspects of reasoning about code that are common to both writing code and explaining code. Student explanations were categorized using the Structure of the Observed Learning Outcome (SOLO) taxonomy. The better programmers were more likely to articulate relational aspects of the algorithms. While earlier work also found such a link, the code writing in those earlier studies was done on paper. This is the first such result where the writing component was done with 'hands on' a computer. Our results add further evidence for the existence of an aspect of reasoning about code that is common to both explaining code and writing code, which in turn suggests that a judicious mix of teaching both code skills and code explaining skills may lead to a more effective process by which novices learn to reason about code.