The measure of coupling used in the following documents is derived from the number of calls made in each class to an "outside" class. That is, one class's measure of coupling is the number of calls it makes to other classes. This number is then normalized over the entire project. The ideal coupling score is 0.0% overall. This means that the module is completely independent from all other modules. Modules with higher coupling scores require more care to modify or extend.
Cohesion is a much more difficult measure to quantify. Instead, each module is given a score from 1 to 9. 1 is the lowest score and means that the module is a mixed-bag, of sorts, and handles many unrelated tasks. 9 is the highest cohesion score and indicates a strongly cohesive module that deals with a single, unified, task. Modules that have low cohesion scores will be more difficult to modify or extend than modules with high cohesion scores.