Choose and choose a distribution.

Select the type of information about the distribution that you want to calculate.

- Probability density
- The probability density function helps identify regions of higher and lower probabilities for values of a random variable. For more information, go to Using the probability density function (PDF).
- Cumulative probability
- The cumulative distribution function (CDF) calculates the cumulative probability for a given x-value. Use the CDF to determine the probability that a random observation that is taken from the population is less than or equal to a certain value. You can also use this information to determine the probability that an observation is greater than a certain value, or between two values. For more information, go to Using the cumulative distribution function (CDF).
- Inverse cumulative probability
- The inverse cumulative distribution function gives the value that is associated with a specific cumulative probability. Use the inverse CDF to determine the value of the variable associated with a specific probability. For more information, go to Using the inverse cumulative distribution function (ICDF).