A random variable whose values are not countable is called a continuous random variable. A continuous random variable is a random variable that can assume any value contained in one or more intervals. Because the number of values contained in any interval is infinite, the possible number of values that a continuous random variable can assume is also infinite (Mann 2012) .

There exist many more continuous probability distributions than we may discuss here. However, be aware that by now a large variety of different discrete and continuous probability distributions are implemented in R (see here). In R probability functions are accessible by generic prefixes, such as r, d, p and q. The r is the generic prefix for random variable generator such as runif(), for the uniform distribution, or rnorm(), for the normal distribution. The d is the generic prefix for the probability density function such as dunif() and dnorm(). The p is the generic prefix for the cumulative density function such as punif() and pnorm(). The q is the generic prefix for the quantile function such as qunif() and qnorm(). Keep that in mind, while we further explore the capacities in R.

The following functions and R-packages are used in this section (in alphabetical order):

R-packages

• latex2exp

Functions

• curve()
• dchisq()
• df()
• dunif()
• length()
• mean()
• pchisq()
• pf()
• pnorm()
• pt()
• punif()
• qchisq()
• qf()
• qnorm()
• qt()
• qunif()
• rchisq()
• rt()
• runif()
• sd()
• seq()
• subset()
• sum()

Plotting Functions

• hist()
• qqnorm()
• qqline()

Citation

The E-Learning project SOGA-R was developed at the Department of Earth Sciences by Kai Hartmann, Joachim Krois and Annette Rudolph. You can reach us via mail by soga[at]zedat.fu-berlin.de.

You may use this project freely under the Creative Commons Attribution-ShareAlike 4.0 International License.

Please cite as follow: Hartmann, K., Krois, J., Rudolph, A. (2023): Statistics and Geodata Analysis using R (SOGA-R). Department of Earth Sciences, Freie Universitaet Berlin.