Description
Floor variance at zero when it lies within the allowed negative roundoff tolerance, returning clamped for an originally negative value.
A statistical term depends on its data summaries, weighting convention, centering, denominator, and boundary rules. A contribution, derivative, domain check, or converted summary answers a narrower question than a complete estimator. Those conventions must match before terms are combined or compared.
Floor variance at zero when it lies within the allowed negative roundoff tolerance, returning clamped for an originally negative value.
When to use this tool
Use Variance Negative Roundoff Tolerance when you need this specific summary conversion, contribution, domain rule, or sensitivity term with matching statistical conventions.
How to use the tool and how it works
- Enter variance, tolerance. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read variance, clamped. Inspect clamped before interpreting the associated values.
Floor variance at zero when it lies within the allowed negative roundoff tolerance, returning clamped for an originally negative value. Require nonnegative tolerance and variance>=-tolerance.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| variance | Variance | Required. Finite number. |
| tolerance | Absolute accepted negative discrepancy in variance units. | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| variance | Variance | Required. Finite number. |
| clamped | Clamped | Required. Boolean. |
{
"input": {
"variance": -0.00001,
"tolerance": 0.0001
},
"output": {
"variance": 0,
"clamped": true
}
}Limitations and assumptions
- This is an explicit numeric acceptance policy, not proof that the input came from a valid variance calculation. Larger negative values are rejected; tolerance has variance units.
- 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
Use a complete estimator or model when a contribution, sensitivity, or domain check is insufficient. Verify the weight semantics, centering, denominator, and sampling assumptions before combining summaries.
References
Similar or alternative tools
- Finite Population Variance Sampling Factor
Calculate factor=(population-sample)/(population-1) and correctedVariance=varianceOfMean*factor.
- Histogram Bin Boundary Roundoff Policy
Classify value below or above edge, treating values within inclusive absolute tolerance as snapped and assigning them according to preferUpper.