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Exponential Distribution

Exponential Distribution

Exponential distribution is used for describing time till next event e.g. failure/success etc.

It has two parameters:

  • scale- inverse of rate ( see lam in poisson distribution ) defaults to 1.0.
  • size- The shape of the returned array.

Example

Draw out a sample for exponential distribution with 2.0 scale with 2x3 size:

from numpy import random

x = random.exponential(scale=2, size=(2, 3))

print(x)

Visualization of Exponential Distribution

Example

from numpy import random
import matplotlib.pyplot as plt
import seaborn as sns

sns.distplot(random.exponential(size=1000), kind="kde")

plt.show()

Result:

exponential distribution

Relation Between Poisson and Exponential Distribution

Poisson distribution deals with number of occurrences of an event in a time period whereas exponential distribution deals with the time between these events.