The document outlines the importance of revising performance descriptors to ensure fair scoring that reflects student achievements, considering factors such as test difficulty and item discrimination. It proposes methods for revising score ranges, including item analysis, standard deviation, a norm-referenced approach, and expert judgment. Each method provides a structured way to assess and adjust score ranges to improve assessment accuracy.

1. Performance
Descriptors

2. Understanding the Need for Revision
• It's essential to ensure that the score ranges assigned to each
performance level are fair and accurately reflect the students'
achievement. Factors to consider include:
 Test Difficulty: Is the test overall easy, moderate, or difficult?
 Item Discrimination: Do the items differentiate between high
and low achievers?
 Student Population: What is the general academic level of the
students?

3. Revising the Score
Ranges
Here are some methods to revise the score ranges:

4. Method 1: Item Analysis
 Calculate item difficulty: Determine the percentage of
students who answered each item correctly.
 Calculate item discrimination: Assess how well each
item differentiates between high and low achievers.
 Adjust score ranges: Based on the item analysis, modify
the score ranges to accurately reflect the difficulty of the
test and the performance of students.

5. Method 2: Standard Deviation
 Calculate the standard deviation: This
measures the spread of scores around the mean.
 Use standard deviation to set cut-offs:
Determine the score ranges for each level based
on multiples of the standard deviation from the
mean.

6. Method 3: Norm-Referenced Approach
 Compare to a reference group: If available,
compare the students' scores to a norm group
(e.g., previous years' data, national norms).
 Set cut-offs based on percentiles: Determine
the score ranges based on specific percentiles
(e.g., top 25%, next 25%, etc.).

7. Method 4: Expert Judgment
 Involve subject matter experts: Seek input
from teachers or content experts to determine
appropriate score ranges.
 Consider curriculum standards: Align the
score ranges with the expectations outlined in
curriculum standards.