Statistics
Confidence Interval Guide
Statistical uncertainty explained.
Range likely containing true parameter.
Formula
CI=x̄±Z×(s/√n). 95%:Z=1.96.
Factors
- Larger sample=narrower
- More variability=wider
- Higher confidence=wider
Frequently Asked Questions
95% confidence?
95% of such intervals contain true parameter.
Narrower?
Increase sample or lower confidence.
CI vs margin of error?
MoE=half CI width. CI[50,60]→MoE=5.