Black Swan Wrote:
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>
> Pylon, aren’t you east coast and employed? What
> are you doing up?
Yes. I am employed and on the East coast (and I am grateful for both as well, actually).
I have developed a really unhealthy study habit of falling asleep with my son room after reading him a book (around 8 PM). I’m just usually so exhausted after work, I can’t help it. Then I wake up in the middle of the night, refreshed and ready to study. So tonight I slept from 8:30 PM to about 12:30 AM, and have now been up for 2 1/2 hours hitting the books. But soon to bed, as my alarm clock will go off at 5:30AM.
Anyway… here are the answers (which I think suck, but more on that tomorrow):
QUESTION 1
Regarding the practical application of value at risk (VAR) for portfolio managers, which of the following statements is FALSE? VAR can:
A)
be used to set risk limits on an absolute level.
B) be used to identify the macroeconomic factors that have the greatest impact on overall portfolio performance.
C) not be used to set risk limits relative to a benchmark.
The correct answer was C) not be used to set risk limits relative to a benchmark.
VAR can be used to set risk limits for a portfolio – either on an absolute level or on a relative basis versus a benchmark.
QUESTION 2
Which of the following factors is the common weakness in historical and Monte Carlo Simulation approach to VAR estimation?
A) Both assume that historical variance-covariance matrix is stable.
B) For some assets you may face model risk.
C) A lot of data is needed for time period of interest.
Your answer: A was incorrect. The correct answer was B) For some assets you may face model risk.
The historical method uses actual returns for the position in question. An advantage of the historical method is not having to assume any particular distribution. A disadvantage is that it assumes past performance is representative of what can occur in the future, which may not be the case. The Monte Carlo simulation method for calculating VAR usually involves generating random numbers with a computer. The generated numbers represent possible returns of the asset or portfolio. An advantage is that Monte Carlo simulation does not require the normality assumption and can accommodate the required assumptions for complex relationships. A disadvantage is the requirement for many managerial assumptions and a great deal of computer time and calculations. The historical method and Monte Carlo Simulation both suffer from modeling risk.
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OK… here’s why I disagree with Schweser…. for question 1 I don’t really know how you would use VAR to set risk limits relative to a benchmark. Would you calculate the VAR of the benchmark and then set a limit as a percetage of that? If so, I don’t remember that being covered in the curriculum. So I went with B. I certainly don’t see how VAR identifies macro-economic risk factors… I thought that was for factor push analysis (or whatever they call it now).
For question 2, I think A is a good answer (actually, I think it’s the best answer). Even though the historical approach does not assume normality, the results it gives are still dependent upon a variance / covariance matrix – just one that isn’t calculated and may not even be calculable. It doesn’t matter – the returns are still dependent upon that matirx and it’s stability over time (I’m assuming we all agree that the Monte Carlo results also depend on matrix stability).
Anyway, I’ll be curious to read your thoughts when I get to work in four hours. Good night for now.