Question on ADS: choose view (of a component) for simulation

I created a component from a layout and wanted to simulate it together with other lumped elements and voltage sources in schematics. There are options on choosing from three different views of the component for simulation, i.e. emModel, layout and schematic. The simulation results I obtained from the three different views are very different. I wonder if there is a guide on which view I should use under which circumstances?

Thanks a lot for the help.