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Reference tables for common probability distributions.

Note: In practice, R computes these values much more precisely than any printed table. These tables are provided for exam reference and hand calculations.


1Standard Normal Distribution Table

The table below gives P(Zz)=Φ(z)P(Z \leq z) = \Phi(z) for the standard normal distribution ZN(0,1)Z \sim N(0, 1).

This table will be generated programmatically when the chapter on the Normal distribution (Chapter 5) is completed.

2Common Distribution Summary

DistributionPMF/PDFE(X)V(X)MGF
Binomial(n,p)(n, p)(nx)px(1p)nx\binom{n}{x}p^x(1-p)^{n-x}npnpnp(1p)np(1-p)(pet+1p)n(pe^t + 1-p)^n
Geometric(p)(p)p(1p)x1p(1-p)^{x-1}1/p1/p(1p)/p2(1-p)/p^2pet/[1(1p)et]pe^t/[1-(1-p)e^t]
Poisson(λ)(\lambda)eλλx/x!e^{-\lambda}\lambda^x/x!λ\lambdaλ\lambdaeλ(et1)e^{\lambda(e^t - 1)}
Uniform(a,b)(a,b)1/(ba)1/(b-a)(a+b)/2(a+b)/2(ba)2/12(b-a)^2/12(etbeta)/[t(ba)](e^{tb}-e^{ta})/[t(b-a)]
Normal(μ,σ2)(\mu, \sigma^2)1σ2πe(xμ)2/(2σ2)\frac{1}{\sigma\sqrt{2\pi}}e^{-(x-\mu)^2/(2\sigma^2)}μ\muσ2\sigma^2eμt+σ2t2/2e^{\mu t + \sigma^2 t^2/2}
Exponential(β)(\beta)1βex/β\frac{1}{\beta}e^{-x/\beta}β\betaβ2\beta^2(1βt)1(1-\beta t)^{-1}
Gamma(α,β)(\alpha, \beta)xα1ex/ββαΓ(α)\frac{x^{\alpha-1}e^{-x/\beta}}{\beta^\alpha\Gamma(\alpha)}αβ\alpha\betaαβ2\alpha\beta^2(1βt)α(1-\beta t)^{-\alpha}
Beta(α,β)(\alpha, \beta)xα1(1x)β1B(α,β)\frac{x^{\alpha-1}(1-x)^{\beta-1}}{B(\alpha,\beta)}αα+β\frac{\alpha}{\alpha+\beta}αβ(α+β)2(α+β+1)\frac{\alpha\beta}{(\alpha+\beta)^2(\alpha+\beta+1)}complex