Suppose That Two Experiments Were Conducted to Compare the Effects

question 11

Essay

Suppose that two experiments were conducted to compare the effects of two new insect repellants. In Experiment X, a simple random sample was taken from the population of River City, and the citizens were randomly assigned to repellant A and repellant B. In Experiment Y, a stratified random sample was taken from the population of River City, and the citizens were randomly assigned to repellant A and repellant B. (River City has 4 geographic areas of town, the NE, NW, SE, and SW quadrants; 100 people from each quadrant were sampled for Experiment B.) The results of the experiments were the same: fewer insects landed on the arms that had been treated with insect repellant A. (a) For each experiment, X and Y, discuss whether one can legitimately infer from each of these experiments that repellant A is better than B? Why or why not? (b) For each experiment, X and Y, discuss whether one can legitimately generalize to the population of River City from each of these experiments? Why or why not?

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Definitions:

Hindsight Bias

The tendency to believe, after an event has occurred, that one would have predicted or expected the outcome, also known as the "knew-it-all-along" effect.

Confounding Variable

An external factor in a research study that correlates with both the dependent and independent variables, potentially skewing results.

Alcoholic Beverage

A drink that contains ethanol, commonly known as alcohol, which is a psychoactive substance.

Control Group

In experimental research, the group that does not receive the treatment or intervention being tested, serving as a baseline for comparison.