Standard deviation
Confidence intervals · Method and input reference
Independent observations. Mean and difference use t intervals (Welch for two groups); proportion uses Wilson; difference in proportions uses Newcombe; SD uses normal-population chi-square; correlation uses Fisher z. Synthetic example: 120 baseline systolic blood pressures (mmHg), with between-person variation. Illustrative data, not clinical evidence.
Open calculator · Compare methods in the decision matrix
Required inputs
- Observations — Numeric observations; preserve the row and column structure described above.
- Confidence level — Enter the method parameter described above.
Review missing values and data coding before running. Sample inputs are synthetic teaching examples.
Implementation
Lifescio implements the method-specific formula using the listed SciPy distribution functions and NumPy array arithmetic. See method help for assumptions.
- scipy 1.15.3: scipy.stats.chi2.ppf
These are pinned library versions; saved results record the versions actually used at runtime.