The assistant principal's small sample research lacks reliability compared to the counselor's broader assessment.
The assistant principal's research is less reliable than the high school counselor's results for several reasons:
Sample size: With only 18 students, the sample size is extremely small and prone to bias. It does not accurately represent the entire population of students who might take AP Chemistry. This small sample size can lead to inaccurate conclusions about the relationship between ACT scores and success in AP Chemistry.
Limited scope: Examining only ACT Science and Reading scores ignores other factors that might contribute to success in AP Chemistry, such as math skills, lab experience, and prior knowledge of chemistry concepts. By focusing on just two variables, the assistant principal's research overlooks important contributors and paints an incomplete picture.
Lack of control: The assistant principal's study is observational, meaning it simply observes existing data without controlling any variables. This lack of control makes it impossible to establish cause-and-effect relationships. Other factors unseen in the data may be influencing the relationship between ACT scores and AP Chemistry performance.
Counselor's expertise: The counselor likely has access to more comprehensive data and knowledge about student performance. They might have considered various factors beyond just ACT scores, such as student course history, grades, teacher recommendations, and extracurricular activities. This broader perspective allows for a more informed and reliable evaluation of students' potential for success in AP Chemistry.
Therefore, while the assistant principal's effort to investigate is commendable, the limitations in sample size, scope, control, and expertise make their research less reliable than the counselor's comprehensive assessment.