Template:Lognormal distribution standard deviation: Difference between revisions

From ReliaWiki
Jump to navigation Jump to search
(Redirected page to Lognormal Distribution Functions)
 
(6 intermediate revisions by one other user not shown)
Line 1: Line 1:
===The Standard Deviation===
#REDIRECT [[Lognormal Distribution Functions]]
The standard deviation of the lognormal distribution,  <math>{{\sigma }}</math> , is given by [[Appendix: Weibull References|18]]]:
 
::<math>{{\sigma }}=\sqrt{\left( {{e}^{2{\mu }'+\sigma'{2}}} \right)\left( {{e}^{\sigma'{2}}}-1 \right)}</math>
 
 
The standard deviation of the natural logarithms of the times-to-failure,  <math>{{\sigma'}</math> , in terms of  <math>\bar{T}</math>  and  <math>{{\sigma}</math>  is given by:
 
::<math>\sigma'=\sqrt{\ln \left( \frac{\sigma^{2}}{{{{\bar{T}}}^{2}}}+1 \right)}</math>

Latest revision as of 05:15, 13 August 2012