Description
Observed versus externally predicted mass residual on an explicit arithmetic or log scale.
Specimen measurements and animal observations depend on a defined body part, reference value, unit, and observation window. A mass fraction, size ratio, or timing share summarizes those inputs. The counting and measurement conventions must stay explicit when comparing specimens or records.
Observed versus externally predicted mass residual on an explicit arithmetic or log scale.
When to use this tool
Use Body Condition Size Reference Residual when you need to compare supplied specimen measurements or observation records under an explicit reference and denominator.
How to use the tool and how it works
- Enter observedMass, predictedMass, logScale. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read residual, relativeMass. Use the output convention below.
Return relativeMass=observedMass/predictedMass. For residual use observedMass-predictedMass when logScale is false and the natural logarithm of their ratio when true; require both masses positive.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| observedMass | Observed Mass | Required. Finite number; strictly above 0. |
| predictedMass | Predicted Mass | Required. Finite number; strictly above 0. |
| logScale | Use natural logarithm of the mass ratio when true, otherwise the signed mass difference. | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| residual | Residual | Required. Finite number. |
| relativeMass | Relative Mass | Required. Finite number. |
{
"input": {
"observedMass": 120,
"predictedMass": 100,
"logScale": false
},
"output": {
"residual": 20,
"relativeMass": 1.2
}
}Limitations and assumptions
- The linear residual has mass units while the logarithmic residual is dimensionless. Predicted mass is supplied; the tool does not fit a body-condition reference or assess animal health.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Signed zero is exported as zero.
Alternative or Complementary methods
Use compatible measurements and observation records to verify the chosen denominator and reference before interpreting a specimen comparison.
References
Similar or alternative tools
- Body Landmark Distance Ratio
Compare supplied landmark distances without species-specific morphology thresholds.
- Predator Prey Size Ratio Term
Descriptive measured size ratios only, without inferring prey suitability or feeding recommendations.