Description
Return score=intersection/union when union is positive or supplied emptyScore when zero, and return empty.
A similarity term depends on the comparison universe, missing-value policy, treatment of repeated features, and normalization. A score can also have a caller-selected value when its mathematical denominator vanishes. Those conventions matter before interpreting a threshold or comparing methods.
Return score=intersection/union when union is positive or supplied emptyScore when zero, and return empty.
When to use this tool
Use Weighted Jaccard Zero Union Policy when you need this particular comparison term, normalization, domain condition, or empty-result policy in a larger matching workflow.
How to use the tool and how it works
- Enter intersection, union, emptyScore. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read score, empty. Inspect empty before interpreting the associated values.
Return score=intersection/union when union is positive or supplied emptyScore when zero, and return empty. Require nonnegative intersection within union and emptyScore within zero through one.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| intersection | Intersection | Required. Finite number; minimum 0. |
| union | Union | Required. Finite number. |
| emptyScore | Empty Score | Required. Finite number; minimum 0; maximum 1. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| score | Score | Required. Finite number. |
| empty | Empty | Required. Boolean. |
{
"input": {
"intersection": 0,
"union": 0,
"emptyScore": 1
},
"output": {
"score": 1,
"empty": true
}
}Limitations and assumptions
- EmptyScore is validated even for a nonempty union. The fallback is an explicit convention, not a mathematically defined division or evidence of matching data.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
- 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. Signed zero is exported as zero.
Alternative or Complementary methods
Compare methods only after aligning feature definitions, missingness, empty policies, multiplicities, and normalizers. Use a complete comparison when the tool returns only one contribution or count check.
References
Similar or alternative tools
- Similarity: Cosine Zero Norm Policy
Compute cosine similarity with an explicit reject/zero undefined-norm policy and a retained defined flag; zero is not silently treated as a measured cosine.
- Similarity: Jaccard Empty Pair Policy
Compute cardinality-based Jaccard similarity with explicit zero/one empty-union convention and a retained defined flag.