MEASURING THE COMPREHENSIBILITY OF Z-SPECIFICATIONS

The effects of natural language comments, meaningful variable names, a nd structure on the comprehensibility of Z specifications are investig ated through a designed experiment conducted with a range of undergrad uate and post-graduate student subjects. The times taken on three asse ssment questions are analysed and related to the abilities of the stud ents as indicated by their total score, with the result that stronger students need less time than weaker students to complete the assessmen t. Individual question scores, and total scorer are then analysed and the influence of comments, naming, structure and level of student's cl ass are determined. In the whole experimental group, only meaningful n aming significantly enhances comprehension. In contrast, for those obt aining the best score of 3/3 the only significant factor is commenting . Finally, the subjects' ratings of the five specifications used in th e study in terms of their perceived comprehensibility have been analys ed. Comments, naming and structure are again found to be of importance in the group when analysed as a whole, but in the sub-group of best p erforming subjects only the comments had an effect on perceived compre hensibility. (C) 1998 Elsevier Science Inc. All rights reserved.