Actuarial Outpost
 
Go Back   Actuarial Outpost > Exams - Please Limit Discussion to Exam-Related Topics > SoA/CAS Preliminary Exams > MAS-I
FlashChat Actuarial Discussion Preliminary Exams CAS/SOA Exams Cyberchat Around the World Suggestions

DW Simpson
Actuarial Jobs

Visit our site for the most up to date jobs for actuaries.

Actuarial Salary Surveys
Property & Casualty, Health, Life, Pension and Non-Tradtional Jobs.

Actuarial Meeting Schedule
Browse this year's meetings and which recruiters will attend.

Contact DW Simpson
Have a question?
Let's talk.
You'll be glad you did.


MAS-I Old Exam S Forum

Reply
 
Thread Tools Search this Thread Display Modes
  #21  
Old 06-06-2019, 04:39 PM
DovidB DovidB is offline
CAS
 
Join Date: Nov 2015
Studying for MAS1
Favorite beer: Beer Hugs
Posts: 25
Default

Try looking for a section hazard rate
Reply With Quote
  #22  
Old 06-06-2019, 05:20 PM
MathDoctorG MathDoctorG is offline
Member
Non-Actuary
 
Join Date: Nov 2010
Location: The 'ville
College: Cornell
Posts: 654
Default

Quote:
Originally Posted by The Disreputable Dog View Post
Is anyone bumping into material or questions about increasing failure rates (IFR) or increasing failure rates on the average (IFRA) in their study material?

I searched for "IFR" and "IFRA" and "increasing failure rate" in the TIA forums, but didn't come up with any results. IDK if that means that they don't cover it, or that I'm searching for it wrong. Has anyone seen it covered in Coaching Actuaries or Mahler?
I don't cover it, other than to mention that failure rate and hazard rate are the same.

Nothing from there has been asked on an exam since that content joined the Exam S syllabus.

They could certainly cherry pick a question from there, but there is already a ton of content for that section, and they've only been asking 2-4 questions from that entire section of material per exam, usually one from my first 2-4 lessons in B.2, and one or two from the later lessons in B.2. I think that even if they eventually get around to asking about this topic it is likely to be 1 question every couple of years.
__________________

MAS-I Course, SRM Course,
TIA Apps
Reply With Quote
  #23  
Old 06-10-2019, 05:02 PM
The Disreputable Dog's Avatar
The Disreputable Dog The Disreputable Dog is offline
Member
CAS
 
Join Date: Dec 2011
Studying for MAS-1
College: Somersby School
Favorite beer: Bulldog Root Beer
Posts: 1,041
Default

Quote:
Originally Posted by MathDoctorG View Post
I don't cover it, other than to mention that failure rate and hazard rate are the same.

Nothing from there has been asked on an exam since that content joined the Exam S syllabus.

They could certainly cherry pick a question from there, but there is already a ton of content for that section, and they've only been asking 2-4 questions from that entire section of material per exam, usually one from my first 2-4 lessons in B.2, and one or two from the later lessons in B.2. I think that even if they eventually get around to asking about this topic it is likely to be 1 question every couple of years.
Thanks! I hadn't hunted through too many past exams, and I was curious if they'd ever snuck a question in there. It seemed unlikely.
Reply With Quote
  #24  
Old 06-10-2019, 11:33 PM
Colymbosathon ecplecticos's Avatar
Colymbosathon ecplecticos Colymbosathon ecplecticos is offline
Member
 
Join Date: Dec 2003
Posts: 6,134
Default

Think about the probability distribution of surviving from age 0 to age x.

If the hazard rate is constant, then the distribution is memoryless and is an exponential distribution. This is often how true accidents are modelled.

If the hazard rate is increasing, the older you get, the more likely you are to die soon. This is how human mortality looks after very early ages.


If the hazard rate is decreasing, the older you get, the more likely it is that you will live much longer. These distributions are useful, for example, for modelling disability claims --- if you are out of work for a week, you might (on average) miss another week --- but if you've been out for two months, we might expect you to be out for four more months (on average).

Exponential distributions are often used as the demarcation between thin-tailed (increasing hazard rate) and fat-tailed (decreasing hazard rate) distributions.
__________________
"What do you mean I don't have the prerequisites for this class? I've failed it twice before!"


"I think that probably clarifies things pretty good by itself."

"I understand health care now especially very well."
Reply With Quote
  #25  
Old 06-11-2019, 12:10 PM
The Disreputable Dog's Avatar
The Disreputable Dog The Disreputable Dog is offline
Member
CAS
 
Join Date: Dec 2011
Studying for MAS-1
College: Somersby School
Favorite beer: Bulldog Root Beer
Posts: 1,041
Default

One of the things that I'm noticing is that ASM focuses most of its reliability material directly on the content in Ross, and Ross focuses very little on lives and mortality. It's all structure functions, minimal cuts and paths, and system survival/expected survival time. I've watched most of the videos in TIA for reliability, and they seem (especially at first) to take a more lives-and-mortality approach. I've spent a lot of time on the former viewpoint, and I love it. Give me some systems with multiple paths and cuts. But I'm looking forward to spending more time on the lives and mortality application in the next go-round.

Having not spent much time with IFRs and IFRAs, I'd also add that I'm pretty sure that I read something about decreasing failure rates and parallel systems with non-identical exponential distributions. If you have a parallel system, then over time you're more likely to be functioning by virtue of the component with the lower hazard rate. So the system will have a decreasing rate due to that. I'm sure I described that poorly, but hopefully the gist was correct.
Reply With Quote
  #26  
Old 06-11-2019, 02:22 PM
Colymbosathon ecplecticos's Avatar
Colymbosathon ecplecticos Colymbosathon ecplecticos is offline
Member
 
Join Date: Dec 2003
Posts: 6,134
Default

Quote:
Originally Posted by The Disreputable Dog View Post
Having not spent much time with IFRs and IFRAs, I'd also add that I'm pretty sure that I read something about decreasing failure rates and parallel systems with non-identical exponential distributions. If you have a parallel system, then over time you're more likely to be functioning by virtue of the component with the lower hazard rate. So the system will have a decreasing rate due to that. I'm sure I described that poorly, but hopefully the gist was correct.
Sure, you start with 1000 exponential RVs with mean 1 and 1000 exponential RVs with mean 9. The average time to failure is 5.

After a while, say 2 time periods, most of the mean 1 guys are gone, but most of the mean 9 guys are still there. Since the exponential is memoryless, you again have a mixture of mean 1 and mean 9 exponential RVs, but not the mixing distribution is not 50/50, but maybe 20/80 or something.
__________________
"What do you mean I don't have the prerequisites for this class? I've failed it twice before!"


"I think that probably clarifies things pretty good by itself."

"I understand health care now especially very well."
Reply With Quote
  #27  
Old 06-11-2019, 08:03 PM
The Disreputable Dog's Avatar
The Disreputable Dog The Disreputable Dog is offline
Member
CAS
 
Join Date: Dec 2011
Studying for MAS-1
College: Somersby School
Favorite beer: Bulldog Root Beer
Posts: 1,041
Default

Unrelated: as someone who's never worked with life contingencies before, I'm finding this illustrative life table a little sobering.
Reply With Quote
  #28  
Old 06-12-2019, 02:09 PM
YetAnotherCareerChanger YetAnotherCareerChanger is offline
Member
CAS
 
Join Date: Jan 2014
Posts: 3,416
Default

Quote:
Originally Posted by The Disreputable Dog View Post
Unrelated: as someone who's never worked with life contingencies before, I'm finding this illustrative life table a little sobering.
As someone who took this test and had the same level of life contingencies knowledge... don't sweat it too much. Understand some of the really basic stuff like how to do premium matching & really read the problems.

There are some low hanging fruit type questions on the life contingency section that you can get if you know a little without getting too in-depth.
Reply With Quote
  #29  
Old 06-12-2019, 06:20 PM
The Disreputable Dog's Avatar
The Disreputable Dog The Disreputable Dog is offline
Member
CAS
 
Join Date: Dec 2011
Studying for MAS-1
College: Somersby School
Favorite beer: Bulldog Root Beer
Posts: 1,041
Default

Thanks! I should have said it better, but I actually meant that I don't like the probabilities associated with my age! It seems to think that there's a chance I won't live healthy and happy to 90.

But I'm glad I'm not the only one without much background in it. ASM makes it seem imminently doable, though I've heard there were some sneaky questions on it in past sittings.
Reply With Quote
  #30  
Old 06-12-2019, 07:15 PM
The Disreputable Dog's Avatar
The Disreputable Dog The Disreputable Dog is offline
Member
CAS
 
Join Date: Dec 2011
Studying for MAS-1
College: Somersby School
Favorite beer: Bulldog Root Beer
Posts: 1,041
Default

Seems like Struppeck didn't think to do a CTRL + F for "morality" before publishing.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -4. The time now is 10:49 AM.


Powered by vBulletin®
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
*PLEASE NOTE: Posts are not checked for accuracy, and do not
represent the views of the Actuarial Outpost or its sponsors.
Page generated in 0.17821 seconds with 9 queries