Rarefaction Species Count at Standardized N Calculator
ExactfinitehypergeometricexpectedrarefactionΣ[1−C(N−ni,n)/C(N,n)],withoutreplacementactualcounts,not Chao1/extrapolation. Actual independently identified specimens,matched units/taxon/cohort/source/edition/calibration and model applicability external;not individual identity,causation,diagnosis,absolute age certainty or validated forecast.
Description
Rarefaction estimates expected observed taxon richness in a smaller sample drawn without replacement from a finite counted inventory.
Rarefaction estimates expected observed taxon richness in a smaller sample drawn without replacement from a finite counted inventory.1
It standardizes sample size without extrapolating beyond the observed total.
When to use Rarefaction Species Count at Standardized N Calculator
Use this tool to apply the stated rarefaction species count at standardized n calculator operation with an explicit input and unit basis.
How to use Rarefaction Species Count at Standardized N Calculator and how it works
- Establish the measurement basis and units described above.
- Enter actualQualifiedTaxonCounts, actualWithoutReplacementRarefactionN and run the tool.
- Read result.expectedObservedTaxonRichness using the output meanings below.
- If input is rejected, correct the stated type, range, ordering or alignment issue and rerun; review successful results under the declared convention.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualQualifiedTaxonCounts | Qualified taxon counts, on the basis specified in the algorithm. | array of number | required; dense; align related rows as specified; further conditions in the algorithm |
| actualWithoutReplacementRarefactionN | Without replacement rarefaction n, on the basis specified in the algorithm. | number | required; finite; integer from 0 to N; further conditions in the algorithm |
Require positive integer taxon counts with total at most 10,000 and integer sample size 0–total. Sum each taxon's probability of appearing using successive hypergeometric absence products.
E[richness] = Σ(1 − C(N−nᵢ,n)/C(N,n)) Apply the declared units, ordering and branch conditions.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the declared output fields. | object |
| result.expectedObservedTaxonRichness | Expected observed taxon count, possibly fractional, for the specified finite sample. | number |
{
"input": {
"actualQualifiedTaxonCounts": [
2,
2
],
"actualWithoutReplacementRarefactionN": 2
},
"output": {
"result": {
"expectedObservedTaxonRichness": 1.6666666666666667
}
}
}Limitations and assumptions
The output applies the declared operation to the values you supply. Establish the measurement basis, units, coefficients and any caller-selected rules before interpreting it. The tool does not independently collect or verify observations or decide whether a model or reference applies.
Supply explicit required fields with the documented types and dense aligned arrays. Unknown fields, wrong types and nonfinite numbers are rejected. Branch-specific constraints are explained above. A successful false boolean, negative signed difference, empty slice or unresolved tie is distinct from an input error. Very large inputs or outputs may be rejected by shared resource limits.
Alternative or Complementary methods
For a related operation, use Dominance Percent Top Taxon Calculator. Dominance percentage records the largest taxon's share of a counted assemblage.
For a related operation, use Dinosaur Bonebed Monospecificity Percent Checker. A focal taxon's specimen fraction measures its share of a taxonomically resolved bonebed inventory.
References
Similar or alternative tools
- Dominance Percent Top Taxon Calculator
Dominance percentage records the largest taxon's share of a counted assemblage.
- Dinosaur Bonebed Monospecificity Percent Checker
A focal taxon's specimen fraction measures its share of a taxonomically resolved bonebed inventory.