Head First Statistics

Appendix B. Statistics Tables: Looking Things Up

Where would you be without your trusty probability tables?

Understanding your probability distributions isn’t quite enough. For some of them, you need to be able to look up your probabilities in standard probability tables. In this appendix, you’ll find tables for the normal, t, and χ² distributions, so you can look up probabilities to your heart’s content.

#1. Standard normal probabilities

This table gives you the probability of finding P(Z < z) where Z ~ N(0, 1). To find the P(Z < z), look up your value of z to 2 decimal places, then read off the probability.

z Note Look up the value of z using the first column and first row...	.00	.01	.02	.03	.04	.05	.06	.07	.08	.09
–3.4	.0003	.0003	.0003	.0003	.0003	.0003	.0003 Note ...then read off the probability from the table.	.0003	.0003	.0002
–3.3	.0005	.0005	.0005	.0004	.0004	.0004	.0004	.0004	.0004	.0003
–3.2	.0007	.0007	.0006	.0006	.0006	.0006	.0006	.0005	.0005	.0005 Note These are the probabilities for P(Z > z) where z is negative.
–3.1	.0010	.0009	.0009	.0009	.0008	.0008	.0008	.0008	.0007	.0007
–3.0	.0013	.0013	.0013	.0012	.0012	.0011	.0011	.0011	.0010	.0010
–2.9	.0019	.0018	.0018	.0017	.0016	.0016	.0015	.0015	.0014	.0014
–2.8	.0026	.0025	.0024	.0023	.0023	.0022	.0021	.0021	.0020	.0019
–2.7	.0035	.0034	.0033	.0032	.0031	.0030	.0029	.0028	.0027	.0026
–2.6	.0047	.0045	.0044	.0043	.0041	.0040	.0039