Search results
Results from the WOW.Com Content Network
In probability theory and statistics, the moment-generating function of a real-valued random variable is an alternative specification of its probability distribution.Thus, it provides the basis of an alternative route to analytical results compared with working directly with probability density functions or cumulative distribution functions.
Exponential generating functions are generally more convenient than ordinary generating functions for combinatorial enumeration problems that involve labelled objects. [3] Another benefit of exponential generating functions is that they are useful in transferring linear recurrence relations to the realm of differential equations.
In probability theory and statistics, the exponential distribution or negative exponential distribution is the probability distribution of the distance between events in a Poisson point process, i.e., a process in which events occur continuously and independently at a constant average rate; the distance parameter could be any meaningful mono-dimensional measure of the process, such as time ...
Assume is discrete random variable taking values on the non-negative integers, which is independent of the , and consider the probability generating function . If the X i {\displaystyle X_{i}} are not only independent but also identically distributed with common probability generating function G X = G X i {\displaystyle G_{X}=G_{X_{i}}} , then
we can use a variant of the positive-order derivative-based OGF transformations defined in the next sections involving the Stirling numbers of the second kind to obtain an integral formula for the generating function of the sequence, {(,) /!}, and then perform a sum over the derivatives of the formal OGF, () to obtain the result in the previous ...
Depending on the values of the parameters, the distribution may vary in shape from almost normal to almost exponential. The parameters of the distribution can be estimated from the sample data with the method of moments as follows: [ 4 ] [ 5 ]
The generator is used in evolution equations such as the Kolmogorov backward equation, which describes the evolution of statistics of the process; its L 2 Hermitian adjoint is used in evolution equations such as the Fokker–Planck equation, also known as Kolmogorov forward equation, which describes the evolution of the probability density ...
Exponential functions with bases 2 and 1/2. In mathematics, the exponential function is the unique real function which maps zero to one and has a derivative equal to its value. The exponential of a variable is denoted or , with the two notations used interchangeably.