Log Series Alpha Proxy
Compute a documented Fisher-lite proxy for the log-series alpha parameter as species count divided by the natural logarithm of total individuals plus one.
Description
Compute a documented Fisher-lite proxy for the log-series alpha parameter as species count divided by the natural logarithm of total individuals plus one.
Log Series Alpha Proxy is a focused biology tool that compute a documented Fisher-lite proxy for the log-series alpha parameter as species count divided by the natural logarithm of total individuals plus one. It calculates locally from the values you enter and exposes the result without changing the source observations.1
When to use Log Series Alpha Proxy
Use Log Series Alpha Proxy when you need to compute a documented Fisher-lite proxy for the log-series alpha parameter as species count divided by the natural logarithm of total individuals plus one. Enter Species count S and Total individuals N using the definitions and units below so the result can be reproduced.
- Species count S
- An integer count or setting greater than or equal to 1.
- Total individuals N
- An integer count or setting greater than or equal to 1.
How Log Series Alpha Proxy calculates the result
The published tool contract uses this rule: Compute a documented Fisher-lite proxy for the log-series alpha parameter as species count divided by the natural logarithm of total individuals plus one.
- Log-series alpha proxy
- The calculated log-series alpha proxy.
Limitations of Log Series Alpha Proxy
The output is an estimate tied to the stated model and coefficients; it is not a direct measurement and should retain that label when reported.
Alternative or Complementary measurements
Retain the original Species count S and Total individuals N values and their units alongside the result. Fisher Alpha is useful when you instead need to solve Fisher's log-series diversity parameter from S = alpha × ln(1 + N/alpha). A finite positive solution exists when the observed species count is smaller than the individual count. ACE Proxy Estimator provides another view by helping you compute the singleton-doubleton proxy Sobs + F1 squared divided by 2 F2, substituting one when F2 is zero. This is not the full abundance-based coverage estimator, which requires the rare-species frequency distribution.
References
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Diversity index — Wikipedia contributors
Similar or alternative tools
- Fisher Alpha
Solve Fisher's log-series diversity parameter from S = alpha × ln(1 + N/alpha). A finite positive solution exists when the observed species count is smaller than the individual count.
- ACE Proxy Estimator
Compute the singleton-doubleton proxy Sobs + F1 squared divided by 2 F2, substituting one when F2 is zero. This is not the full abundance-based coverage estimator, which requires the rare-species frequency distribution.
- Bootstrap Richness Proxy
Compute the limited richness proxy Sobs + singletons divided by sample count. A full bootstrap richness estimator requires each species' observed incidence frequency.