Software Testing Methodologies Dichotomies

Ambiguities and Contradictions
Domain ambiguities are holes in the input space
These holes may lie either within the domains or somewhere in the cracks between domains
The number contradictions possible is two, namely, overlapped domain specifications and overlapped closure specifications
The image show ambiguities, missing boundary, overlapped domains and dual closure

Simplifying the Topology
'simplify' is the reaction of both programmers and testers to complex domains
There are three generic cases: Concavities, holes and disconnected pieces
Programmers introduce bugs and testers misdesign test cases by: smoothing out concavities (image (a)), filling in holes (image (b)) and joining disconnected pieces (image (c))

Rectifying Boundary closures
If domain boundaries are parallel but have closure that go every way (left, right, left, ....) the natural reaction id to make closures go the dame way as shown in image