Estimates of Population Parameters

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Estimates of Population Parameters
1. Population sizeCapture–recapture (for small population sizes)   N = s/p where p = r/swhere s is the sample size captured and marked, and the sample size of the second capture; r is the number of marked individuals in the second capture; N is the population size

2. Measures of diversity(a) Species diversity:(i)Simpson's indexwherePi is the proportion of individuals/biomass to the total sample of the ith species;s is the total number of species(ii)Shannon–Wiener index(b) Population diversity:(i)Nucleotide diversity (π)where L is the length of DNA sequence; n is the number of sequences examined; Πij is the number of nucleotide differences between the ith and jth sequences; Ne is the effective population size; u is the mutation rate(ii)Allele frequency datahomozygosity of population j (Hj)heterozygosity (allele diversity) of population j (hj)hj = 1 − Hjaverage heterozygosity of s populations (hs)gene frequency variations between populations (FST)where L is the number of alleles examined of a given locus; pij is the gene frequency of allele i in population j; p̄i is the average gene frequency of allele i in s populations(c)Genetic distance:(i)Genetic distance between two DNA sequences (K) using the Kimura 2 parameter modelwhere P is the proportion of transitions; Q is the proportion of transversions; K is the number of substitutions per base site(ii)Estimate of genetic distance based on allele frequencies (D)where nj is the sample size of population j