Link Between Discrete and Continuous Distributions
It is possible to represent certain discrete random variables as well as random variables involving both a continuous and a discrete part with a generalized probability density function, by using the Dirac delta function. For example, let us consider a binary discrete random variable taking −1 or 1 for values, with probability ½ each.
The density of probability associated with this variable is:
More generally, if a discrete variable can take n different values among real numbers, then the associated probability density function is:
where x1, …, xn are the discrete values accessible to the variable and p1, …, pn are the probabilities associated with these values.
This substantially unifies the treatment of discrete and continuous probability distributions. For instance, the above expression allows for determining statistical characteristics of such a discrete variable (such as its mean, its variance and its kurtosis), starting from the formulas given for a continuous distribution of the probability.
Read more about this topic: Probability Density Function
Famous quotes containing the words link between, link, discrete and/or continuous:
“If parents award freedom regardless of whether their children have demonstrated an ability to handle it, children never learn to see a clear link between responsible behavior and adult privileges.”
—Melinda M. Marshall (20th century)
“The secret of biography resides in finding the link between talent and achievement. A biography seems irrelevant if it doesn’t discover the overlap between what the individual did and the life that made this possible. Without discovering that, you have shapeless happenings and gossip.”
—Leon Edel (b. 1907)
“The mastery of one’s phonemes may be compared to the violinist’s mastery of fingering. The violin string lends itself to a continuous gradation of tones, but the musician learns the discrete intervals at which to stop the string in order to play the conventional notes. We sound our phonemes like poor violinists, approximating each time to a fancied norm, and we receive our neighbor’s renderings indulgently, mentally rectifying the more glaring inaccuracies.”
—W.V. Quine (b. 1908)
“If an irreducible distinction between theatre and cinema does exist, it may be this: Theatre is confined to a logical or continuous use of space. Cinema ... has access to an alogical or discontinuous use of space.”
—Susan Sontag (b. 1933)