skbio.math.diversity.alpha.robbins

skbio.math.diversity.alpha.robbins(counts)[source]

Calculate Robbins’ estimator for the probability of unobserved outcomes.

Robbins’ estimator is defined as

\[\frac{F_1}{n+1}\]

where \(F_1\) is the number of singleton OTUs.

Parameters:

counts : 1-D array_like, int

Vector of counts.

Returns:

double

Robbins’ estimate.

Notes

Robbins’ estimator is defined in [R53]. The estimate computed here is for \(n-1\) counts, i.e. the x-axis is off by 1.

References

[R53](1, 2) Robbins, H. E (1968). Ann. of Stats. Vol 36, pp. 256-257.