Seshagiri,

For model-based testing, I work with Matlab models (Simulink and Stateflow).

I would claim that a “good” test generation tool should indicate to the user what each test vector is doing. For example, the STB tool provides a list of all the test objectives that each test vector “achieves”. This tool will also indicate exactly which step within the test vector achieves the indicated test objective.

Other test generation tools that I use, do not provide as nice of indication on what each test vector is testing.

Depending on who I talk to, some people want each test vector to test only 1 thing, while others want to generate as few of test vectors as possible. This will impact whether more or less test vectors are generated than when generating the test manually. The test tools that I work with, tend to test multiple things in any one test vector. The one tool will either merge tests together, or generate one test vector per test objective.

So I would say that there is no one answer to the number of tests generated. This is dependent on your test generation tool, and what you want from the tests.

Scott