Final answer:
The control group in an experiment helps establish a baseline measurement and controls other factors that might affect results, allowing researchers to attribute differences in outcomes between the control and the experimental groups to the independent variable being tested.
Step-by-step explanation:
In an experiment, the control group establishes a baseline measurement and/or helps to eliminate other factors that would affect your results. By providing the control group with a placebo or no treatment, researchers can ensure that the experimental manipulation is the only difference between the control and experimental groups. This allows for comparison and more accurate conclusions regarding the effect of the independent variable on the dependent variable.
The effectiveness of a control group in an experiment is due to its role in controlling for other variables that might influence the results. By keeping these factors consistent across both the experimental and control groups, researchers can attribute any differences in outcomes to the experimental manipulation. Having a control group also facilitates a double-blind study, where both the subjects and researchers do not know who is receiving the active treatment, reducing bias.
Selecting from the options given:
- Experimental controls eliminate the need for large sample sizes.
- Experimental controls eliminate the need for statistical tests.
- Experimental controls reduce the number of measurements needed.
- Experimental controls allow comparison between groups that are different in only one independent variable.
The correct answer is the last one, as experimental controls do allow for meaningful comparisons by isolating the effect of the independent variable on the dependent variable.