Punnett-based Trihybrid/Multi-gene Probability Calculator

Inspectable records

Ledger state

The current ledger marks this instrument verified with errata that must be applied at binding time.

Area

Biology, Medicine & Pharmacology (educational estimates only — every panel labeled not-medical-advice)

Tranche

tranche-5

Evidence ID

t5-116

Ledger rows

1

No ledger note is attached.

Review findings

The core product rule is standard under independent assortment for simultaneous per-locus events. The instrument cannot receive an unconditional PASS until it explicitly defines genotype versus phenotype inputs, decimal-versus-percent representation, validation of locus count, and the precise independence assumption. The educational and not-medical-advice labeling is appropriate, but it does not resolve those computational ambiguities.

Formula and scope findings

• The product rule is correct only when the per-locus events are independent and the requested outcome is the simultaneous occurrence of one specified event at every locus.
• The specification alternates between genotype probability and phenotype probability. A phenotype probability can require summing multiple genotype probabilities before applying the product rule; the current formula does not define that case.
• The role of 'number of loci' is underspecified: it must equal the number of supplied per-locus probabilities, or the calculator must reject the input.
• The formula does not state whether probabilities are supplied as decimals from 0 to 1 or as percentages from 0 to 100.

Unit assumptions

• Probabilities are dimensionless decimal fractions in the inclusive range 0 to 1; for example, 25% must be entered as 0.25.
• The number of loci is an integer of at least 3 and must equal the length of the per-locus probability list.
• Each per-locus probability refers to one specified genotype or one already-combined phenotype event.
• The loci assort independently; no linkage, epistasis, conditional dependence, or other dependence is included.
• The combined result is a decimal probability; multiply by 100 only when displaying it as a percentage.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The plain product rule has no division-by-zero trap and no genuine multi-regime formula branch, but an implementation without strict validation can return Infinity for extreme inputs and can accept values outside the probability domain. Percentage-versus-fraction ambiguity can also produce invalid results if units are not explicit.

Errata and corrections

Tranche errata

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "number_of_loci": 3,
    "per_locus_probabilities": [
      0.25,
      0.5,
      0.25
    ]
  },
  "expected_outputs": {
    "combined_probability": 0.03125,
    "combined_probability_percent": 3.125
  },
  "working": "P = 0.25 × 0.50 × 0.25\n0.25 × 0.50 = 0.125\n0.125 × 0.25 = 0.03125\n0.03125 × 100 = 3.125%"
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_WITH_ERRATA
• evidence-tranche5/tranche5-results.json
• BOUNDARY_HAZARD_CATALOG.json