How would vou set up the experiment to test the hypothesis that: “cocoa improves cognitive performance’? Consider the three set ups below. Which of the three setups 1s most reliable and why?
1. Researchers measure cognitive capacity;’ performance of a group of participants before the experiment. Researchers then allow participants to eat a predetermined amount of chocolate before reassessing their cognitive performance. Ifthe group recorded a higher average improvement after the chocolate, then we can conclude that cocoa does improve cognitive performance.
2. Researchers divide participants into two groups. They then measure cognitive performance of both groups before the experiment. Researchers then allow one group to eat a predetermined amount of chocolate, while the other group isasked to refrain from chocolate. Researchers then reassess both groups’ cognitive performance. If the experimenter group recorded a higher average improvement over the control group, then we can conclude that that cocoa does improvecognitive performance.
3- Researchers divide participants into two groups. They then measure cognitive performance of both groups before the experiment. Researchers then allow participants to eat a predetermined amount of chocolate; while the other group isserved cocoa free ‘fake’ chocolate that looks exactly like the real one. Researchers then reassess both groups’ cognitive performance. If the experiment group recorded a higher average improvement over the control group, then we canconclude that that cocoa does improve cognitive performance.
