Chapter 6, Problem 23REAE

Solution

To Decide:

Whether the given situation is an example of observational study, survey, or randomized controlled experiment.

This is an experiment.

Given:

Various types of batteries each run a flashlight constantly until the light goes off.

Concepts Used:

An experiment necessarily imposes some treatment to the subjects to measure the effect on variables of interest. A randomized controlled experiment involves randomly selecting a treatment group and a control group to ensure that the treatment is indeed the cause of the effect observed in the variables of interest.

In an observational study variables of interest are observed without imposing any treatment on the subjects.

In a survey subjects are asked direct questions about the variables of interest.

Description:

This is an experiment because it treatment is imposed in the form of different batteries put into flashlights, but this is not a randomized controlled experiment since there is no randomization of samples or separation of treatment and control groups.

Conclusion:

This is an experiment.