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Section A.1 Common Critical Values

(a) Two-Tailed
(b) One-Tailed
Figure A.1.1. Normal Distribution Critical Values
\((1-\alpha)\) \(\alpha\) \(z_{\alpha/2}\) \(z_\alpha\)
90% \(0.10\) \(1.645\) \(1.28\)
95% \(0.05\) \(1.96\) \(1.645\)
98% \(0.02\) \(2.33\) \(2.05\)
99% \(0.01\) \(2.575\) \(2.33\)
Table A.1.2. Common Normal Distribution Critical Values