Significance level (alpha) is a human-made threshold in statistical hypothesis testing — the maximum acceptable probability of a Type I error (rejecting a true null hypothesis). Standard values are 0.05 and 0.01, chosen by convention to balance error rates against the power of a test. It operationalizes the trade-off between false positives and false negatives in decision-making under uncertainty. The persistence mechanism is the statistical convention encoded in textbooks, software documentation, and scientific reporting standards. [formal: gradus significantis | substrate: mind | horizon: a life | explicit: yes | epoch: 0.90]
Accepted ontology entry
significance level
Significance level (alpha) is a human-made threshold in statistical hypothesis testing — the maximum acceptable probability of a Type I error (rejecting a true null hypothesis). Standard values are 0.05 and 0.01, chosen by convention to ba…
Definition
Why it is in scope
A human-made threshold in statistical hypothesis testing — the maximum acceptable probability of a Type I error (rejecting a true null hypothesis), typically set at 0.05 or 0.01. Built to persist through standardized α notation and decision protocols that determine whether observed evidence constitutes sufficient grounds to reject the null hypothesis.
Names and aliases
- significance levelen · CANONICAL
Relations from this entry
- cmrxj3acr03cmsoacx73fal1oDERIVED_FROM →
which-came-first test: statistics as a mathematical discipline (dating to the 17th century with Bernoulli, Huygens) predates significance level as a formal concept (Neyman-Pearson framework, 1928-1933). Significance level was built on top of the prior concept of statistics. DERIVED_FROM direction is correct.
- cmrxj3acr03cmsoacx73fal1oDEPENDS_ON →
Significance level as a procedure requires statistical methods to operate now — computing p-values, setting alpha thresholds, comparing test statistics against distributions. Remove statistics and the significance level procedure ceases to function. Complements the accepted DERIVED_FROM by capturing the operational dependency.
Relations to this entry
No accepted relations in this direction.
Record identity
- Created
- Aug 9, 2026, 10:12 PM UTC
- Content hash
- 76ac10dd2b7a52e26551a6b1b6c7035160bbbd4db3a7c4ec4db8410d1553bb46