Final answer:
Control subjects must be representative of the larger population for the findings of the study to be generalizable. This requires a diverse and randomly selected sample which reflects the various characteristics of the entire population. Random assignment into experimental and control groups further ensures the validity of the research results.
Step-by-step explanation:
It is imperative that control subjects be representative of the larger population from which they are drawn, especially in sociological or psychological research. When conducting an experiment or study, such as assessing the efficacy of tutoring on algebra students in a particular city, researchers must ensure that their sample group encompasses a diverse cross-section of students. This diversity should include variations in income, family situations, races, ethnicities, religions, and geographic areas in order to accurately reflect the composition of the city. A representative sample allows researchers to generalize their findings to the entire population, without the results being skewed due to an unrepresentative sample that could introduce bias.
The process begins by selecting a population of interest and narrowing it down to a manageable subset, thereafter a random sample of individuals is chosen. With random assignment, researchers can then divide participants into experimental and control groups, ensuring that each person has an equal chance of being placed in either group. This methodology is crucial for maintaining the integrity of the experimental design and obtaining valid results that can be extrapolated to the wider population.