Description
Split oldWeight into firstPart and its remainder, replace its squared contribution in sumSquaredWeights, and compare effective sizes sumWeights²/squaredSum before and after.
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.
Split oldWeight into firstPart and its remainder, replace its squared contribution in sumSquaredWeights, and compare effective sizes sumWeights²/squaredSum before and after.
When to use this tool
Use Effective Sample Size Weight Split 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 sumWeights, sumSquaredWeights, oldWeight, firstPart. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read before, after, change. Use the output convention below.
Split oldWeight into firstPart and its remainder, replace its squared contribution in sumSquaredWeights, and compare effective sizes sumWeights²/squaredSum before and after. Require positive summaries, feasible split weights, and positive new squared sum.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| sumWeights | Sum Weights | Required. Finite number; strictly above 0. |
| sumSquaredWeights | Sum Squared Weights | Required. Finite number; strictly above 0. |
| oldWeight | Original weight being split without changing total weight. | Required. Finite number; minimum 0. |
| firstPart | First Part | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| before | Before | Required. Finite number. |
| after | After | Required. Finite number. |
| change | Change | Required. Finite number. |
{
"input": {
"sumWeights": 4,
"sumSquaredWeights": 8,
"oldWeight": 2,
"firstPart": 1
},
"output": {
"before": 2,
"after": 2.6666666666666665,
"change": 0.6666666666666665
}
}Limitations and assumptions
- Total weight is held fixed. Splitting a weight does not create independent observations, and the result does not verify actual sampling information, standard errors, or a weighting design.
- 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
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