Description
Calculate a scale mean under a supplied unanswered-item denominator policy.
Assessment records distinguish presented items, responses, deliberate skips, missingness, accommodations, versions and reference populations. A score contribution depends on its chosen denominator and weight, while one confidence gap is not a full calibration study. Recorded observations and timing differences do not establish learner ability or an appropriate intervention.
Calculate a scale mean under a supplied unanswered-item denominator policy.
When to use this tool
Use Scale Subscore Available Item Denominator when you already have scoreSum, answeredItems, plannedItems, excludeUnanswered and need to calculate a scale mean under a supplied unanswered-item denominator policy.
How to use the tool and how it works
- Enter scoreSum, answeredItems, plannedItems, excludeUnanswered. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read denominator, meanScore. Use the output convention below.
Require nonnegative safe whole plannedItems and answeredItems<=planned; choose answered or planned, require the chosen denominator>0, and divide signed scoreSum by it.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| scoreSum | Score Sum | Required. Finite number. |
| answeredItems | Answered Items | Required. Safe integer; minimum 0. |
| plannedItems | Planned Items | Required. Safe integer; minimum 0. |
| excludeUnanswered | Exclude Unanswered | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| denominator | Answered count when excluding unanswered, otherwise planned count; the selected count must be positive. | Required. Safe integer. |
| meanScore | Mean Score | Required. Finite number. |
{
"input": {
"scoreSum": 12,
"answeredItems": 3,
"plannedItems": 4,
"excludeUnanswered": true
},
"output": {
"denominator": 3,
"meanScore": 4
}
}Limitations and assumptions
- No item-level values, scoring range, missingness mechanism or valid scale completion rule is checked. This does not impute responses.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use the full assessment manual, item records, population reference and research design for score interpretation. Review missingness, exposure, accommodations and comparability; local labels or contributions do not replace psychometric analysis or an appropriate educational assessment.
References
Similar or alternative tools
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