Which grading method may lead to inconsistencies among different students' performances?

Grading by assumption can lead to inconsistencies among different students' performances because it relies on preconceived notions or biases rather than objective measurements of student achievement. When instructors make assumptions about a student's capabilities or effort based on past performance, behavior, or other subjective factors, it can influence the grades awarded without a clear basis in the actual work submitted. This can result in varied grading outcomes that do not accurately reflect individual student understanding or skills.

In contrast, grading uniformly involves applying the same criteria consistently across all students, which helps to ensure fairness and allows for a clearer comparison of performances. Grading by desire focuses on what a student wants to achieve, which may not align with their actual performance, while grading by impulse may reflect transient feelings rather than an assessment of the work itself. Both of these methods can introduce additional variability, but grading by assumption is particularly problematic as it fundamentally alters the basis upon which students are evaluated.