Which mathematical model did the teacher use to estimate the student's true summative score?

• A. Average
• B. Median
• C. Linear trend
• D. Decaying average

Answer: (C)

Modeling performance over time with a linear trend captures how a student’s scores grow or decline in a steady way. By fitting a straight line to past assessments, you account for the direction and rate of change, which helps estimate the underlying level of mastery more reliably than a single number. This approach separates consistent growth from random fluctuations, giving a clearer picture of the student’s true summative ability.

An average treats all scores as equally informative, ignoring when they occurred and the direction of change. A median focuses on a middle value and ignores trends altogether. A decaying average weighs recent scores more but still smooths data in a way that can miss longer-term patterns. The linear trend uniquely uses time to reflect how performance is progressing, making it the best fit for estimating the true summative score.