Actuarial Outpost June 2019 Exam STAM Thread
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#51
04-19-2019, 12:16 PM
 A Pimp Named Slickback Member Join Date: Oct 2008 Posts: 241

I'm using ASM and doing GOAL practice problems.
#52
04-22-2019, 07:40 AM
 KristinaO Member CAS Join Date: Apr 2015 Posts: 36

Can anybody who has gone through Intro to Ratemaking and Loss reserving help with something in chapter 3, specifically Example 3.1?

a, How do we get Y=4.7534 + 0.1085X I tried to do it via finding slope and then b (Y=m+bx) but was not getting the same answer.
b, Still example 3.1 in calculating loss cost corresponding to Sep. 1 2002 they get X=6.16 but I am not sure how - mostly about .16 part

Is the above example 3.1 a type of question one can expect to see on STAM exam?

Is anybody else frustrated with this book as much as I am? It is awful. I wish ASM would give an option to purchase the additional "new" material for those who have their older versions of ASM manuals.

Any help is greatly appreciated.
#53
04-22-2019, 11:03 AM
 daaaave David Revelle Join Date: Feb 2006 Posts: 3,051

As you are calling this Example 3.1, you are using the 3rd edition of the Intro to Ratemaking text, not the 4th edition, which is the one on the syllabus. There are some topics in Chapter 5 that are added in the 4th edition that aren't in the 3rd edition that might get 1-2 questions. The other main differences are Chapters 3 and 4 are swapped in the new edition, all of the examples are changed from being in terms of specific dates to being in terms of accident years (e.g., this example replaces 1996 with AY 1, 1997 with AY 2, etc.)

a. They are doing linear regression. I don't think this part of the problem is likely, as linear regression isn't explicitly on the syllabus, but you can do it on your calculator. In data mode, enter the X values (0, 1, 2, 3, 4) in L1, the Y values (4.782, etc.) in L2. Then in stats do 2-var stats with xData: L1 and yData: L2, and scroll down to a=0.1085 and b=4.7534. The output is in the form Y = aX + b.

b. The 0.16 is because we are projecting from 6/30/1996 to 9/1/2002. That is a difference of 6 years (to get from 1996 to 2002) and 2 months (all of July and all of August). 2 months is 2/12 = 1/6 = 0.16 of the year. The part of the calculation after they do the regression is reasonable to appear on the exam.
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#54
04-22-2019, 07:55 PM
 KristinaO Member CAS Join Date: Apr 2015 Posts: 36

Quote:
 Originally Posted by daaaave As you are calling this Example 3.1, you are using the 3rd edition of the Intro to Ratemaking text, not the 4th edition, which is the one on the syllabus. There are some topics in Chapter 5 that are added in the 4th edition that aren't in the 3rd edition that might get 1-2 questions. The other main differences are Chapters 3 and 4 are swapped in the new edition, all of the examples are changed from being in terms of specific dates to being in terms of accident years (e.g., this example replaces 1996 with AY 1, 1997 with AY 2, etc.) a. They are doing linear regression. I don't think this part of the problem is likely, as linear regression isn't explicitly on the syllabus, but you can do it on your calculator. In data mode, enter the X values (0, 1, 2, 3, 4) in L1, the Y values (4.782, etc.) in L2. Then in stats do 2-var stats with xData: L1 and yData: L2, and scroll down to a=0.1085 and b=4.7534. The output is in the form Y = aX + b. b. The 0.16 is because we are projecting from 6/30/1996 to 9/1/2002. That is a difference of 6 years (to get from 1996 to 2002) and 2 months (all of July and all of August). 2 months is 2/12 = 1/6 = 0.16 of the year. The part of the calculation after they do the regression is reasonable to appear on the exam.
Got it, thank you! I greatly appreciate your help. I will see if I can get 4th edition but I may just work with what I got, but I will do more research on the changes you mentioned.
#55
04-23-2019, 09:09 AM
 ToBeAnActuaryOrNotToBe Member SOA Join Date: May 2014 Favorite beer: The ones in red solo cups. Posts: 674

Am I crazy, or is the uniform distribution not on the formula sheets provided at all?
#56
04-23-2019, 10:05 AM
 Jim Daniel Member SOA Join Date: Jan 2002 Location: Davis, CA College: Wabash College B.A. 1962, Stanford Ph.D. 1965 Posts: 2,718

Quote:
 Originally Posted by ToBeAnActuaryOrNotToBe Am I crazy, or is the uniform distribution not on the formula sheets provided at all?
A Beta RV with a = b = 1 is a Uniform RV on 0 to theta.
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#57
04-23-2019, 06:16 PM
 A Pimp Named Slickback Member Join Date: Oct 2008 Posts: 241

Maybe I'm having a brain fart, shouldn't the numerator for the first term in the derivative have a negative sign?

-30e^(-1000/theta)

Since we are doing the derivative of 1-e^(-1000/theta)

Sent from my iPad using Tapatalk
#58
04-23-2019, 06:25 PM
 Jim Daniel Member SOA Join Date: Jan 2002 Location: Davis, CA College: Wabash College B.A. 1962, Stanford Ph.D. 1965 Posts: 2,718

Yes, but then the derivative of -1000/theta should have a plus sign. They just put the negative sign in an odd place.

Quote:
 Originally Posted by A Pimp Named Slickback Maybe I'm having a brain fart, shouldn't the numerator for the first term in the derivative have a negative sign? -30e^(-1000/theta) Since we are doing the derivative of 1-e^(-1000/theta) Sent from my iPad using Tapatalk
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#59
04-29-2019, 07:37 PM
 TBG214 SOA Join Date: May 2017 College: University of Florida Alum Posts: 2

I just finished all of the lessons and first pass problems on TIA. How are you guys studying after finishing the lessons? I want to start cranking out practice problems, but I legit don't remember a lot from earlier sections since there is so much material and I started way back in January.

Really want to pass on the first try for once so it would be awesome if anyone can share how they are approaching the exam at this stage in the study process.

Thanks!
#60
05-02-2019, 11:38 AM
 ryanpez Member SOA Join Date: Mar 2012 Location: Omaha, NE Studying for STAM College: Youngstown State Alumni Posts: 121

How long does it take to prepare for this exam? 2/3/4 months?
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