Block 96: Confidence Intervals

Concepts

• Confidence interval formula: x̄ ± z*(σ/√n)
• scipy.stats.t.interval() for t-based CIs
• Interpreting CIs: what 95% really means
• Bootstrapping for non-parametric CIs

Code Examples

See exercise below.

Exercise

Compute 95% CI for the mean of a column in a real dataset. Bootstrap: resample 1000 times, compute mean each time. Plot distribution. Extract 2.5th and 97.5th percentiles.

Homework

What does '95% confidence interval' actually mean? Write the statistically correct interpretation. Thursday