Laplace Distribution for the Probability Distribution Calculator

Density Function
The Laplace (or Double Exponential) distribution has the probability density function:

f(x) = 1/(2b) * e[-(|x-a|/b)], -∞ <x<∞

where

a is the location parameter (mean)
b is the scale parameter
e is the base of the natural logarithm, sometimes called Euler's e (2.71...)
Distribution Function
The cumulative distribution function (the term was first introduced by Wilks, 1943) for the Laplace distribution is:
F(x) = 1/2 * e[-(a-x)/b], x < a
  = 1 - {1/2 * e[-(x-a)/b]}, x ³ a
L
This field displays the current variate value for the Laplace distribution. When you edit this value (either manually or with the microscrolls), Statistica computes the associated p-value for the specified parameters.
p
This field displays the p-value computed from the specified variate value and parameters or you can enter a desired p-value (either manually or edit the existing value with the microscrolls) and compute the critical value of the distribution for the specified parameters.
Location, Scale
Specify here the location and scale parameters of the distribution, a and b, respectively. If one or both of these parameters are changed, then the p-value will be recomputed based on the respective variate value.