Question

What is a controlled experiment?

Answer 1

A controlled experiment is a scientific investigation designed to test a hypothesis by manipulating one or more independent variables while keeping all other variables constant. The purpose of a controlled experiment is to isolate the effect of the independent variable(s) on the dependent variable, allowing researchers to establish cause-and-effect relationships.

In a controlled experiment, there are typically two groups involved:

1. **Experimental Group**: This group is subjected to the treatment or condition being tested, meaning the independent variable is manipulated in this group.

2. **Control Group**: This group does not receive the experimental treatment and is kept under the same conditions as the experimental group, except for the independent variable. This allows researchers to compare results and determine if any observed changes in the experimental group can be attributed to the manipulation of the independent variable.

Key elements of a controlled experiment include:

- **Randomization**: Participants or subjects may be randomly assigned to either the experimental or control group to eliminate bias.

- **Replication**: The experiment should be repeatable by other researchers to verify the results.

- **Consistency**: All conditions aside from the independent variable should be held constant to ensure that any differences in outcomes can be attributed to the manipulation of the independent variable.

By carefully controlling variables, researchers can obtain reliable and valid results that contribute to scientific understanding.