I've built a simulator that imagines people using a website. It produces a signal similar to that of an appropriately instrumented website in production. I am treating the analytic system as the device under test and stimulating it as would any design engineer of any other system.
Traffic surges simulated and then analyzed.
Some circuits are easily analyzed with swept sine waves. Random noise works well too if you have the computing power to analyze the output.
Some circuits have behavior that cannot be tested without a more realistic signal such as one obeying a signaling protocol.
My simulator produces an appropriately steady signal such that anomalies in the analytics indicates anomalies or limitations in the analytic process. Steady can mean a predictably steady stream of web traffic surges who's analysis benefits server system design.
This is a variation of functional testing and a domain appropriate variation of test-driven development.