Template:Characteristics of the exponential distribution alta: Difference between revisions

From ReliaWiki
Jump to navigation Jump to search
(Created page with '===Characteristics=== The characteristics of the 1-parameter exponential distribution can be exemplified by examining its parameter, lambda, <math>\lambda ,</math> and the effe…')
 
Line 18: Line 18:
:• The 1-parameter exponential reliability function starts at the value of 1 at  <math>T=0</math> . It decreases thereafter monotonically and is convex.
:• The 1-parameter exponential reliability function starts at the value of 1 at  <math>T=0</math> . It decreases thereafter monotonically and is convex.
:• As  <math>T\to \infty </math> ,  <math>R(T\to \infty )\to 0</math>.
:• As  <math>T\to \infty </math> ,  <math>R(T\to \infty )\to 0</math>.
Effects of  <math>\lambda </math>  on the Failure Rate Function
====Effects of  <math>\lambda </math>  on the Failure Rate Function====


The failure rate function for the exponential distribution is constant and it is equal to the parameter  <math>\lambda </math> .
The failure rate function for the exponential distribution is constant and it is equal to the parameter  <math>\lambda </math> .

Revision as of 23:43, 6 February 2012

Characteristics

The characteristics of the 1-parameter exponential distribution can be exemplified by examining its parameter, lambda, [math]\displaystyle{ \lambda , }[/math] and the effect lambda has on the [math]\displaystyle{ pdf }[/math] , reliability and failure rate functions.

Effects of [math]\displaystyle{ \lambda }[/math] on the pdf

Pdf plot of the exponential distribution.


• The scale parameter is [math]\displaystyle{ \tfrac{1}{\lambda } }[/math] .
• As [math]\displaystyle{ \lambda }[/math] is decreased in value, the distribution is stretched out to the right, and as [math]\displaystyle{ \lambda }[/math] is increased, the distribution is pushed toward the origin.
• This distribution has no shape parameter as it has only one shape, i.e. the exponential. The only parameter it has is the failure rate, [math]\displaystyle{ \lambda }[/math] .
• The distribution starts at [math]\displaystyle{ T=0 }[/math] at the level of [math]\displaystyle{ f(T=0)=\lambda }[/math] and decreases thereafter exponentially and monotonically as [math]\displaystyle{ T }[/math] increases, and is convex.
• As [math]\displaystyle{ T\to \infty }[/math] , [math]\displaystyle{ f(T)\to 0 }[/math].
• This [math]\displaystyle{ pdf }[/math] can be thought of as a special case of the Weibull [math]\displaystyle{ pdf }[/math] with [math]\displaystyle{ \beta =1 }[/math] .


Reliability plot of the exponential distribution.


Effects of [math]\displaystyle{ \lambda }[/math] on the Reliability Function

• The 1-parameter exponential reliability function starts at the value of 1 at [math]\displaystyle{ T=0 }[/math] . It decreases thereafter monotonically and is convex.
• As [math]\displaystyle{ T\to \infty }[/math] , [math]\displaystyle{ R(T\to \infty )\to 0 }[/math].

Effects of [math]\displaystyle{ \lambda }[/math] on the Failure Rate Function

The failure rate function for the exponential distribution is constant and it is equal to the parameter [math]\displaystyle{ \lambda }[/math] .

Failure Rate plot of the exponential distribution.