Understanding The New Statistics

4

Confidence Intervals, ErrorBars, and p Values

This chapter presents more about CIs, including some beautiful pictures and two further approaches to CI interpretation. The main issues are

• Error bars, and how they can show various types of information in figures
• Cat's-eye pictures that show the beautiful shape of a CI
• The fourth approach to interpreting CIs—in terms of their shape
• The relation between CIs and p values
• The fifth approach to interpreting CIs—with reference to p values
• One-sided CIs, which correspond to one-tailed NHST

The Error ...