Rubric Descriptor Matrix

Build a criterion-by-performance-level rubric from caller descriptors.

Description

A rubric descriptor matrix associates each criterion with each performance level.

A rubric descriptor matrix associates each criterion with each performance level. A complete cell count is separate from having nonblank descriptors.^[1]

Build a criterion-by-performance-level rubric from caller descriptors.

When to use Rubric Descriptor Matrix

Use this tool to build a criterion-by-performance-level rubric from caller descriptors.

Prepare the lesson timeline, roster, observations or assessment labels requested. Use consistent units and exact identifiers, then choose comparison criteria appropriate to the activity.

How to use Rubric Descriptor Matrix and understand its results

Prepare the lesson timeline, roster, observations or assessment labels requested. Use consistent units and exact identifiers, then choose comparison criteria appropriate to the activity.
Enter criteria, levels, descriptors using the field table and calculation rules, then run the tool.
Read cells, missingCellIndexes. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
criteria	Criteria	list of string	Required
levels	Levels	list of string	Required
descriptors	Descriptors	list of string	Required

Enter nonempty distinct exact criteria and levels with exactly their product in descriptors. Use criterion-major order; return formatted cell strings and zero-based indexes of blank trimmed descriptors.

cell_i=criteria[floor(i/levelCount)]/levels[i mod levelCount] + trimmed descriptor_i

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
cells	Cells	list of string
missingCellIndexes	Missing cell indexes	list of number

json

{
  "input": {
    "criteria": [
      "accuracy",
      "clarity"
    ],
    "levels": [
      "basic",
      "strong"
    ],
    "descriptors": [
      "few correct",
      "all correct",
      "unclear",
      "clear"
    ]
  },
  "output": {
    "cells": [
      "accuracy/basic: few correct",
      "accuracy/strong: all correct",
      "clarity/basic: unclear",
      "clarity/strong: clear"
    ],
    "missingCellIndexes": []
  }
}

Limitations and assumptions

Missing text is returned as an audit finding rather than an input error. Criterion/level labels are not normalized, and descriptor quality is not evaluated.

Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Rubric Format Selector: Choose an analytic or holistic rubric from feedback needs and grading time. For a complementary task, use Discussion Rubric Score: Score asynchronous discussion criteria and flag low-scoring rubric dimensions.

References

Rubric Descriptor Matrix — tool.io

Similar or alternative tools

Rubric Format Selector
Choose an analytic or holistic rubric from feedback needs and grading time.
Discussion Rubric Score
Score asynchronous discussion criteria and flag low-scoring rubric dimensions.