The Correct Answer and Explanation is:
Based on the text provided, the correct answer is:
The initial sections were not assigned to the students by randomization.
Explanation
The fundamental flaw in Professor Abad’s conclusion stems from a common mistake in interpreting data: confusing correlation with causation. She observes a correlation, a higher average score in one section, and incorrectly concludes a cause, that the students in that section are academically superior. This conclusion is unsupported because her study lacks random assignment.
In a proper scientific or statistical experiment designed to compare two groups, subjects must be randomly assigned to each group. Randomization helps ensure that, on average, the groups are similar in every respect except for the variable being tested. In this case, since students likely chose their own class sections based on their personal schedules, preferences, or even friendships, the groups were not random. This self-selection process introduces confounding variables that offer alternative explanations for the difference in test scores.
For example, Section 1 might be an 8:00 AM class, which could attract more disciplined or motivated students who prefer to start their day early. Conversely, Section 2 might be a late afternoon class chosen by students who have jobs or other commitments. It is also possible that a group of high-achieving students, perhaps from the same major, decided to register for Section 1 together.
Because these and other potential differences between the student populations in each section were not controlled for through randomization, we cannot confidently attribute the higher exam scores in Section 1 to the students’ inherent academic ability. The difference could easily be the result of motivation, scheduling preferences, or pre-existing social groups. Therefore, Professor Abad’s conclusion that one group is superior is an invalid leap from an observational finding.
