Contents

cumnor()

Usage:

cumnor(x [,upper:T or lower:F]), x REAL

Keywords: probabilities

cumnor(Z) computes the probabilities that a standard normal (mean 0,
variance 1) random variable would be less than the elements of the
vector, matrix, or array Z.  The size and shape of the result is the
same as that of Z.

cumnor(Z, upper:T) and cumnor(Z, lower:F) compute upper tail
probabilities.  For large positive Z, these may preserve significant
digits lost by the mathematically equivalent 1 - cumnor(Z).

Two-tailed P values associated with an observed value of z, may be
computed as 2*cumnor(abs(z),upper:T) or 2*(1 - cumnor(abs(z))).

Example:
Two-tail normal P-value for z_obs = 1.841
  Cmd> 2*cumnor(1.841,upper:T) # or 2*(1 - cumnor(1.841))
  (1)     0.06562

See also invnor().