Matched samples refer to a set of data points or individuals that have been carefully selected and paired based on specific characteristics or variables. This process of matching ensures that the samples are similar in all aspects except for the variable being studied, allowing for a more accurate comparison and analysis. Matched samples are commonly used in research studies and experiments to control for potential confounding factors and increase the validity of the results. By using matched samples, researchers can confidently draw conclusions and make informed decisions based on the data collected.