Geometric Distribution

Top  Previous  Next

Fathom Reference > Fathom Operators, Functions, and Units > Distribution Functions > Geometric Distribution

The geometric distribution can be used to explore how long you have to wait for a given event to occur, given the probability of that event. The probability, p, defaults to 0.5. We speak of X being randomly chosen with geometric probability from the set of values {min, min + scale, min + 2scale, …, } where min and scale default to 0 and 1.

 

_img130

Shows three different probabilities comparing how long, on average, you have to wait for success

 

geometricCumulative(x, p,

scale, min)

This function computes the cumulative probability, Pr(X ≤ x), where X is randomly chosen as described above and where p is the probability of success on a given trial.

geometricProbability(x, p,

scale, min)

The geometric probability function calculates the probability, P(X = x).

geometricQuantile(c, p,

scale, min)

The geometric quantile function computes the value x, such that Pr(X ≤ x) = c.