Which movies embrace the same dramatic elements of good against evil and the search for power as wagner's ring cycle, proving that today's audiences still want the same story as nineteenth-century audiences?

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.