Margin of error
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.
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Required inputs
- Population standard deviation — Enter the method parameter described above.
- Sample size — Enter the method parameter 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.norm.isf
These are pinned library versions; saved results record the versions actually used at runtime.