Template:Exponential Statistical Properties: Difference between revisions

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==Exponential Statistical Properties==
#REDIRECT [[Exponential Distribution Functions]]
===The Mean or MTTF===
The mean, <math>\overline{T},</math> or mean time to failure (MTTF) is given by:
 
 
::<math>\begin{align}
  \bar{T}= & \int_{\gamma }^{\infty }t\cdot f(t)dt \\
  = & \int_{\gamma }^{\infty }t\cdot \lambda \cdot {{e}^{-\lambda t}}dt \\
  = & \gamma +\frac{1}{\lambda }=m 
\end{align}</math>
 
 
Note that when <math>\gamma =0</math>, the MTTF is the inverse of the exponential distribution's constant failure rate. This is only true for the exponential distribution. Most other distributions do not have a constant failure rate. Consequently, the inverse relationship between failure rate and MTTF does not hold for these other distributions.
 
{{Median}}
 
 
{{Mode}}
 
 
 
{{Standard Deviation}}
 
 
 
{{Exponential Reliability Function}}
 
{{One-Parameter Exponential Reliability Function}}
{{Exponential Conditional Reliability}}
 
 
 
{{Exponential Reliable Life}}
 
 
 
{{Exponential Failure Rate Function}}

Latest revision as of 08:08, 10 August 2012