Description
Return probability mass over a closed ordinal-index interval.
Ordinal labels have an order, but adjacent categories need not be equally spaced measurements. Index distances, cumulative targets and weighted medians preserve a specified ordering while probability normalization, equality at a median boundary and distance costs remain distinct conventions.
Return probability mass over a closed ordinal-index interval.
When to use this tool
Use Ordinal Probability Mass Interval when evaluating the stated ordered-label target, distance or mass convention.
How to use the tool and how it works
- Enter probabilities, first, last. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read intervalMass. Use the output convention below.
Return probability mass over a closed ordinal-index interval. Require nonempty probabilities in [0,1] with sum within 1e-12 of one and valid first <= last; intervalMass sums both endpoint positions.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| probabilities | Ordered class probabilities in [0,1]; total must be within 1e-12 of one. | Required. Array of finite number; maximum items 256. |
| first | First | Required. Safe integer; minimum 0. |
| last | Last | Required. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| intervalMass | Interval Mass | Required. Finite number. |
{
"input": {
"probabilities": [
0.2,
0.3,
0.5
],
"first": 1,
"last": 2
},
"output": {
"intervalMass": 0.8
}
}Limitations and assumptions
- No probability calibration, class spacing or joint uncertainty is assessed; the normalization tolerance is explicit.
- 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 meaningful ordered labels and an appropriate ordinal model; evaluate prediction quality with costs and probability assumptions justified for the actual categories.
References
Similar or alternative tools
- Classification: Ordinal Step Error Distance
Return signed and absolute ordinal class-index errors.
- Ordinal Median Class Boundary
Select a weighted ordinal median under an equality policy.