Can a two parameter Weibull Distribution be written as an exponential family form?

8 views (last 30 days)
Keqiao Li
Keqiao Li on 27 Mar 2017
Commented: Keqiao Li on 28 Mar 2017
Hi guys, I was wondering whether the two parameter Weibull Distribution belongs to a exponential family?

Answers (1)

John BG
John BG on 27 Mar 2017
Keqiao
makedist generates exactly the same points when the setting
Weibull a = Exponential mu
a:scale b:shape
.
pd1=makedist('Weibull','a',2,'b',2) % a:scale b:shape
nx=[0:.1:10]
y=pdf(pd1,nx)
plot(y,'r');grid on
hold all
pd2=makedist('Weibull','a',2,'b',1) % a:scale b:shape
y2=pdf(pd2,nx)
plot(y2,'b');
pd3=makedist('Exponential','mu',2) % a:scale b:shape
y3=pdf(pd3,nx)
plot(y3,'k')
.
.
y2 blue and y3 black are completely overlapped.
isequal(y2,y3)
ans =
1
if you find these lines useful would you please mark my answer as Accepted Answer?
To any other reader, if you find this answer of any help would you please click on the thumbs-up vote link,
thanks in advance for time and attention
John BG
  1 Comment
Keqiao Li
Keqiao Li on 28 Mar 2017
Hi John, thank you for your answer. Your answer is quite useful. But since Weibull distribution can be reduced to exponential distribution, this is because the shape parameter is "1" and a = mu? Is this the only condition when Weibull distribution can be considered as a exponential family (not just exponential distribution)?

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by