Difficulty of CS2A

Considering the exam has now been moved online and “open book” would you imagine examiners creating a more difficult paper since they would “expect’ students to make use of the open book? This is also because , usually the first 3-4 questions of each paper are theory based and “easy’ but this time around they will not be included.

Lastly what are your thoughts about first writing down the computation on a piece of paper (where we are more familiar with) and then quickly copying it onto word. Do you think that would waste too much time?

 

Thank you Andy. I imagine most of the questions which include large computations will be the multiple choice ones whereas the smaller computations will be included which shouldn’t be too hard on Word.

Considering we are going to be the “guinea pigs”, without any official sample papers might I add, I sincerely do hope the examiners take this into consideration when deciding how complicated to make the exam.

we have come a looonggg way from the original CT4 and CT6 with now one exam for both of them, online, with the inclusion of R.

 

Very difficult...

 

I agree. Only "CT" exam I wasn't able to fully finish. Not sure if it was due to word format, lack of focus while doing it at home or it's me not being prepared enough.

 

yes and the R paper was a another story. I thought the R paper was going to be easy after doing past papers.

 

Anybody able to shed light on how they answered Q3 iv on the the Time Series question?

 

After differencing I got model in form dY(t)=0.5*dY(t-1) + e(t) +0.7*e(t-1).
Then from part iii) I got answer A, i.e. Cov(e(t),dY(t))=sigma^2 and Cov(e(t-1),dY(t))=(0.5 + 0 + 0.7)*sigma^2=1.2 sigma^2
For part iv) I've written gamma_0 as
gamma_0=Cov(dY(t),dY(t))= Cov(0.5*dY(t-1) + e(t) +0.7*e(t-1),dY(t))
= 0.5*gamma_1 + Cov(e(t),dY(t)) + 0.7*Cov(e(t-1),dY(t))
using result from part iii):
=0.5*gamma_1 + sigma^2 + 0.7*1.2 * sigma^2= 0.5*gamma_1 + 1.84*sigma^2.
I took similar approach for gamma_1.
Hope it will be readable.

 

Thats perfect Michal. Makes sense.
Really appreciate the response and hope the exam went well for you.

 

I'm glad other people are saying it was difficult. I found paper A really tough - definitely the hardest exam I've sat so far. There seemed to be quite a few questions on areas which aren't commonly examined, and despite thinking I had fully grasped differencing I couldn't get to the answer on Q3.

And then, yeah I thought I was very ready for paper B but that was a disaster. Seemed like a quarter of the marks available weren't possible if you couldn't append an extra column to some data (which granted seems like a basic I should perhaps have been able to do!)

 

I am appearing for IAI exam in 2 wks time. So I am practicing UK papers , too. I did not find CS2A that difficult, only Q7 I could not do and some 2 marks ones like Q3 iv) and Q8 vi) I am unable to get the answers given.

But as u said, CS2B is way too difficult. Q3 is a total disaster, as like u, i have no clue how to proceed from i) itself, forget about the later parts. For Q1, I can do only upto iv). and the fact that each sub-section carries so heavy marks, its scary even if u cant do one sub-section.

India usually have tougher question papers, so i am dreadful about CS2B.

PS. If u could send me your solution to Q7, I would be grateful.