Description
Return the numerator and denominator contribution of one binary feature to a Tversky score under supplied nonnegative asymmetry weights.
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 the numerator and denominator contribution of one binary feature to a Tversky score under supplied nonnegative asymmetry weights.
When to use this tool
Use Similarity: Tversky Single Feature Contribution 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 inLeft, inRight, alpha, beta. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read result. Expand result to inspect the returned fields.
Return numeratorContribution one only when a feature is in both sets. Return denominatorContribution one for both, alpha for left-only, beta for right-only, or zero for neither, with nonnegative penalties, inside result.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| inLeft | In Left | Required. Boolean. |
| inRight | In Right | Required. Boolean. |
| alpha | Alpha | Required. Finite number. |
| beta | Beta | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| result | Result | Required. Object. |
{
"input": {
"inLeft": true,
"inRight": false,
"alpha": 0.3,
"beta": 0.7
},
"output": {
"result": {
"numeratorContribution": 0,
"denominatorContribution": 0.3
}
}
}Limitations and assumptions
- This is one feature's Tversky term, not the final ratio. Penalties and membership flags are supplied rather than chosen or verified from data.
- Outputs are nested inside result. 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
- Dice Overlap Count Contribution
Return exact decimal numerator twice overlap and denominator firstSize+secondSize using BigInt, plus numeric dice.
- Ranking Discount Shared Item Contribution
Return one/log2(rank+1) when relevant and zero otherwise, requiring one-based integer rank from one through one million.