Statistical Functions Available in STATA

 
STATA V7 Distribution Functions (STATA V7 [U] 16.3.2 pp. 113-119)
Distribution Cumulative
F(x) = P(X<=x)
Density f(x) Inverse cumulative
F-1(p)={x|P(X<=x)=p}
Random generator
Uniform uniform()
Normal (0, 1] norm(z)

normden(z)
normden(x,m,s)

invnorm(p)
t ttail(df,t) tden(df,t) invttail(df,p)
F F(df1,df2,F) fden(df1,df2,f) invF(df1,df2,p)
Chi-square chi2(df,x)
chi2tail(df,x)
invchi2(df,p)
invchi2tail(df,p)
Chi-square (non-central)1 nchi2(df,l,x) invnchi2(df,l,p)
Gamma gammap(a,x) gammaden(a,b,g,x) invgamma(a,p)
Beta betaden(a,b,x)
Exponential (0,1)
Logistic (0,1)
Studentized
Weibull
Binomial binomial(n,k,p)4 invbinomial(n,k,p)5
Poisson 1-gamma(k+1,x)

NOTES: Functions in red with 'tail' suffix are are reversed cumulative functions so that ftail(x)=1-F(x)
1. Not available in SYSTAT.
2. binomial(n,k,p) is the probability of "k or more successes in n trials when the probability of success on a single trial is p"