In a 1927-32 western electric company study on the effect of lighting on worker productivity, productivity increased with each increase in lighting but then also increased with every decrease in lighting. if it is assumed that the workers knew a study was in progress, this is an example of(a) the effect of the treatment unit(b) the placebo effect(c) the control group effect(d) sampling error(e) voluntary response bias

The answer is: B) the placebo effect

Explanation:

The placebo effect occurs when people experience a benefit after an inactive substance or treatment is administered to them. The Hawthorne Experiment led to a variation of the placebo effect which is called the Hawthorne Effect.

The Hawthorne Effect occurs when the study subjects respond to the mere attention paid to them by the study personnel. The study subjects react positively just because they are being part of an experiment.