What does a Flat Object mean in the Pole Position Client Server Model benchmarks (see picture below)?

I am trying to figure out which benchmarks I should look at for a small and simple web application… should I be looking at the Flatobject benchmarks? Benchmarks doc found at http://polepos.sourceforge.net/results/PolePositionClientServer.pdf
Given that the other tests of the benchmark test
I would say that a flat object is an object with no relation to any other entity/table, and which directly extends
java.lang.Object.