A researcher investigates the effectiveness of an experimental weight‐loss program. Sixteen volunteers will participate, half assigned to the experimental program and half placed in a control group. In a study such as this, it would be good if the average weights of the subjects in the two groups were approximately equal at the start of the experiment. Here are the weights, in pounds, for the 16 subjects before the study begins.

First, use a matching procedure as the method to form the two groups (experimental and control) and then calculate the average weight per group. Second, assign participants to the groups again, this time using random assignment (cut out 20 small pieces of paper, write one of the weights on each, and then draw them out of a hat to form the two groups). Again, calculate the average weight per group after the random assignment has occurred.

Compare your results to those of the rest of the class. Are the average weights for the groups closer to each other with matching or with random assignment? In a situation such as this, what do you conclude about the relative merits of matching and random assignment?

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