IQ Heritability Calculator
Falconer twin variance illustration h²=2(rMZ−rDZ), actual cohort traits, unclippedestimate under strong independent equal environment/additivity assumptions. Not individual IQ genetic percentage, ancestry ranking, causality or direct additive variance measurement. Actual independently matched observations/units and protocol, not diagnosis, causal mechanism, clinical decision or validated individual prediction.
Description
Falconer's twin illustration compares monozygotic and dizygotic within-pair correlations under strong population-model assumptions.
Falconer's twin illustration compares monozygotic and dizygotic within-pair correlations under strong population-model assumptions.1
This tool returns twice their difference without clipping it or treating it as an individual's genetic share of IQ.
When to use IQ Heritability Calculator
This tool returns twice their difference without clipping it or treating it as an individual's genetic share of IQ.
How to use IQ Heritability Calculator and how it works
- Prepare monozygotic within pair correlation, dizygotic within pair correlation, using the input definitions and matching units below.
- Enter the required fields and run IQ Heritability Calculator.
- Read result.value using the units, signs and ordering explained below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualMonozygoticWithinPairCorrelation | Actual Monozygotic Within Pair Correlation. Use the units and matching context stated in the calculation below. | number | Required; finite; other constraints below |
| actualDizygoticWithinPairCorrelation | Actual Dizygotic Within Pair Correlation. Use the units and matching context stated in the calculation below. | number | Required; finite; other constraints below |
Require each within-pair correlation between -1 and 1 inclusive. Return 2*(rMZ-rDZ) without clipping to 0–1. This is the Falconer twin illustration under external equal-environment and additive assumptions, not individual genetic attribution or a causal estimate from correlations alone.
illustrativeH2=2*(rMZ-rDZ) Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Numeric model result on the ratio, score, constant or density basis explained above. | number |
{
"input": {
"actualMonozygoticWithinPairCorrelation": 0.6,
"actualDizygoticWithinPairCorrelation": 0.3
},
"output": {
"result": {
"value": 0.6
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Polygenic Risk Score Calculator for a complementary operation: An additive polygenic score sums aligned effect-allele dosages multiplied by externally established weights.
Use Neuroimaging Power Analysis Calculator for a complementary operation: Neuroimaging power depends on effect, variance, design, test family and spatial assumptions.
References
-
IQ Heritability Calculator — tool.io
Similar or alternative tools
- Polygenic Risk Score Calculator
An additive polygenic score sums aligned effect-allele dosages multiplied by externally established weights.
- Neuroimaging Power Analysis Calculator
Neuroimaging power depends on effect, variance, design, test family and spatial assumptions.