How to use the genetic drift variance calculator
Estimate the random change in allele frequency per generation. Enter allele frequency p, effective population size in the fields above; the std. deviation of change per generation, heterozygosity lost per generation are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “small population drift”, “effective population”, “founder effect”, “calculate genetic drift variance”, “find std. deviation of change per generation”.
Formula
Variables
- p — Allele frequency p
- N — Effective population size
Worked example
With allele frequency p = 0.5, effective population size = 50, the calculator gives std. deviation of change per generation ≈ 0.05; heterozygosity lost per generation ≈ 1 %.
Frequently asked questions
What is the genetic drift variance calculator used for?
Estimate the random change in allele frequency per generation. It helps with questions such as “small population drift”, “effective population”, “founder effect”.
What is the formula for the genetic drift variance calculation?
Std. deviation of change per generation = √(p × (1-p) / (2 × N)). Heterozygosity lost per generation (%) = 100 / (2 × N). Here p is allele frequency p, N is effective population size.
What inputs do I need for the genetic drift variance calculator?
You need allele frequency p, effective population size. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the genetic drift variance calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the genetic drift variance result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.