




















PROBABILITY DISTRIBUTION CHARTS 



Select Distribution 

3 
LN 
REJECT 




Lognormal 








PDF, Reliability, Unreliability, Hazard Rate,
Cumulative Hazard Rate 











































































































































































































































































































































































































GROUP DATA 















Average 
3.7197 















Sample Standard Deviation 
2.1078337 















Optimal Number of Groups [Sturges' Rule] 
7.6438562 















Number of Groups 
8 















Total Number of Observations 
100 















RESIDUAL
LIFETIME 















Residual Lifetime Percentile 
50.0% 















Median Residual Lifetime 
3.4230769 















Standard Error of Median Residual Lifetime 
0.1923077 















GOOGNESS
OF FIT 















Probability Distribution Function 
LN 
P 














Mean μ 
1.1953169 
P 














Standard Deviation σ 
0.6696591 















Number of Parameters Estimated m [m ≤ n] 
2 















Total Number of Parameters n 
2 















ChiSquare Σ(OiEi)2/Ei 
11.267153 















Degrees of Freedom df 
5 















Test χ2 
11.070498 















Accept / Reject 
REJECT 















ChiSquare Rank 
7 


































































The marker P identifies the probability
distribution's parameters. 










































































































































































































































































































































































Legend 






































SYMBOL 
VARIABLE 












T1=T 
Start of Interval [Age at Start of Mission] 












T2=T+t 
End of Interval 












t=T2T1 
Duration of Interval [Mission Time] 












τ=(T1+T2)/2 
Interval Midpoint 












i 
Group 












H 
Histogram 












f(τ) 
Probability Density Function at Midpoint 












R(T) 
Reliability [Survival or Cumulative Proportion
Surviving] at T 












R(T+t) 
Reliability [Survival or Cumulative Proportion
Surviving] at T+t 












Q(T) 
Unreliability [Failure or Cumulative Proportion
Terminating] at T 












Q(T+t) 
Unreliability [Failure or Cumulative Proportion
Terminating] at T+t 












λ(τ) 
Hazard Rate at Midpoint 












Mi 
Median Residual Lifetime 












Copyright © 2010 by Macroknow Inc. All Rights
Reserved. 





















































