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Format: VoseExpon(b, U)
The Expon(b) is a right-skewed distribution bounded at zero with a mean of b. It only has the one shape. Examples of the Exponential distribution are given below:
If risk events are assumed to occur randomly in time (i.e. follow a Poisson process) and the average time between events equals β, then the time between each consecutive event will be distributed according to Expon(β). So, for example, if an insurer sees that some particular type of natural disaster occurs on average once every 5.5 years, the time between such consecutive disasters can be modeled as Expon(1/5.5) years.
The memoryless property of the Exponential distribution also means that the time until the next event (even though it may have been some time since the last such event occurred) also follows an Expon distribution. This implies a rather aesthetically pleasing property: the right tail of an Exponential distribution takes the same shape as its whole.
The Exponential and Geometric distributions are the only distributions that allow for independence between additional waiting time and elapsed waiting time (sometimes described as a process that has no memory). When a Poisson distribution is a good approximation to a Binomial, an Exponential distribution is also a good approximation to a Geometric.
The Exponential distribution is sometimes called the Negative Exponential. The Exponential distribution is a special case of the Weibull distribution: Weibull(1, b) = Expon(b).
VoseExponential generates values from this distribution or calculates a percentile.
VoseExponentialObject constructs a distribution object for this distribution.
VoseExponentialProb returns the probability density or cumulative distribution function for this distribution.
VoseExponentialProb10 returns the log10 of the probability density or cumulative distribution function.
VoseExponentialFit generates values from this distribution fitted to data, or calculates a percentile from the fitted distribution.
VoseExponantialFitObject constructs a distribution object of this distribution fitted to data.
VoseExponentialFitP returns the parameters of this distribution fitted to data.
