Continuous Probability Distributions

For any positive constant eqn, one function eqn is a probability density function and the function eqn is the corresponding cumulative distribution function for x > 0. (A distribution of this form is called an exponential distribution.) This applet computes probabilities for this distribution, for a specified choice of eqn.

How to use the applet

  1. In the table at the top, enter a value of eqn to specify the distribution, and enter values for a and b. All three values must be positive numbers, with eqn and eqn. Note, these cells act like a spreadsheet application; to change an entry, click on it, delete the current value, type a new one, and then press enter.
  2. Below the table, plots of the probability density function, eqn, and the cumulative distribution function, eqn, are drawn according to the equations
    eqn
    and
    eqn.
    You may choose to shade different regions of the probability density function, eqn, eqn, or eqn.
  3. You may update the region of interest by entering new values of a and b into the table at the top.

The applet

No Java Plug-in support for applet, see http://java.sun.com/products/plugin/