Post-Hoc Power From d and n Calculator
Bounded off line reference: Observed power limitations, HoenigandHeisey2001; no fabricated exactt-power model. Explicit topics premise, limitations. No full/live authority, clinical diagnosis, safe-use approval or universal individual outcome.
Description
Observed post-hoc power is derived from the observed effect and test design.
Observed post-hoc power is derived from the observed effect and test design.1
Interpreting it as new evidence for a study result can restate information already present in the test statistic. The calculation and input requirements are explained below.
When to use Post-Hoc Power From d and n Calculator
Choose exactly premise or limitations.
How to use Post-Hoc Power From d and n Calculator and how it works
- Prepare the measurements or independently established model inputs described below, with matching units and observation scope.
- Enter the required fields and run Post-Hoc Power From d and n Calculator.
- Read the result fields using the formula, output 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 |
|---|---|---|---|
| topic | Topic. Use the units and matching context stated in the calculation below. | string | Required; other constraints below |
Choose exactly premise or limitations. Return the corresponding embedded explanatory text. This reference tool does not accept d or n and does not compute a power estimate.
text=reference[topic] Apply the input ordering, units and branch conditions stated above.
| Topic | Purpose |
|---|---|
| premise | Explains why observed power is not independent evidence. |
| limitations | Explains the need for design, variance, effect and test assumptions. |
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.text | Text. Interpret its unit, sign, order or availability flag as explained above. | string |
{
"input": {
"topic": "premise"
},
"output": {
"result": {
"text": "Post hoc power computed from the observed effect is not independent evidence for a study result and largely restates its test statistic. Prefer prospective independently justified effect assumptions and confidence intervals."
}
}
}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 Independent t-Test Power .80 Sample Size for a complementary operation: Two-group power planning requires a proposed effect and significance level.
Use SEM Minimum Sample 10-Per-Parameter Rule for a complementary operation: A participants-per-parameter heuristic is a nominal planning budget.
References
-
Post-Hoc Power From d and n Calculator — tool.io
Similar or alternative tools
- Independent t-Test Power .80 Sample Size
Two-group power planning requires a proposed effect and significance level.
- SEM Minimum Sample 10-Per-Parameter Rule
A participants-per-parameter heuristic is a nominal planning budget.