PropertyBased Software Engineering Measurement Lionel Briand Sandro Morasca

Property-Based Software Engineering Measurement Lionel Briand, Sandro Morasca, Victor Basili IEEE TOSE Jan 96 briand 4 1

Basic Assumptions u Properties can determine the type of measurement briand 4 2

Systems and Modules – p 70 u. A system, S, is a pair <E, R> where E is the set of elements and R is the set of relations between the elements u A system m = <Em, Rm> is a module of S iff Em is a subset of E and Rm is a subset of Em cross Em and Rm is a subset of R. briand 4 3

Size u PS 1 - Nonnegativity u PS 2 - Null value u PS 3 - Module additivity briand 4 4

Is LOC a size measure? u What is E and R? u What is Size(S)? u Are all the properties satisfied – Nonnegativity – Null value – Module additivity briand 4 5

Which of the following are size measures? Why or why not? u Halstead’s vocabulary, h u Halstead’s length, N u The briand 4 constant function zero 6

Can you think of u. A size metric that does not satisfy the properties? u. A non-size metric that does satisfy the properties? briand 4 7

Length u PL 1 – Nonnegativity u PL 2 – Null value u PL 3 – Nonincreasing monotonicity u PL 4 – Nondecreasing monotonicity u PL 5 – Disjoint modules briand 4 8

Length u Can you think of a length measure other than those mentioned in the paper? (nesting depth and DIT (depth of inheritance tree). briand 4 9

Length u “Properties L 1 through L 5 hold when applying the admissible transformation of the ratio scale. Therefore, there is no contradiction between our concept of length and the definition of length measures on a ratio scale. ” u What briand 4 does this mean? 10