Description
Update prior odds by a supplied likelihood ratio.
Cognitive research records can encode stimuli, response timing, probability assumptions and observation support. Local differences and caller-defined tolerance labels do not establish perceptual validity, a cognitive mechanism, statistical equivalence or a clinical assessment.
Update prior odds by a supplied likelihood ratio.
When to use this tool
Use Perceptual Choice Prior Odds Shift when checking a supplied cognitive-task timing, stimulus, probability or evidence convention.
How to use the tool and how it works
- Enter priorProbability, likelihoodRatio. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read priorOdds, posteriorOdds, posteriorProbability. Use the output convention below.
Update prior odds by a supplied likelihood ratio. Require priorProbability strictly between zero and one and likelihoodRatio >= 0; priorOdds = p/(1-p), posteriorOdds = odds*LR, posteriorProbability = p*LR/(1-p+p*LR).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| priorProbability | Prior Probability Unit: 1. | Required. Finite number; strictly above 0; strictly below 1. |
| likelihoodRatio | Likelihood Ratio Unit: 1. | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| priorOdds | Prior Odds | Required. Finite number. |
| posteriorOdds | Posterior Odds | Required. Finite number. |
| posteriorProbability | Posterior Probability Unit: 1. | Required. Finite number. |
{
"input": {
"priorProbability": 0.5,
"likelihoodRatio": 3
},
"output": {
"priorOdds": 1,
"posteriorOdds": 3,
"posteriorProbability": 0.75
}
}Limitations and assumptions
- The likelihood ratio must refer to the same hypotheses/evidence; no perceptual model, evidence independence or calibration is established.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- 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. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use a validated study design, calibrated measurements and appropriate statistical/professional interpretation for cognitive or health conclusions.
References
Similar or alternative tools
- Cue Validity Uninformative Base Flag
Compare cue correctness with a baseline and tolerance.
- Perceptual Match Stimulus Luminance Ratio
Divide supplied test-stimulus luminance by positive reference luminance without modeling perceptual equality.