Ok so a basic quant question. The question gives you a table with annual returns on ABC Mutual Fund from 1991-2000 (10 data points)
Question is : If the risk-free rate was 4.0%, during the period 1991 - 2000, what is the sharpe ratio for ABC Mutual fund for the period 1991-2000?
You need to calulcate the variance first. In the answer sheet, they do (n-1) for the denominator. I would think, they would say this is a sample. Are you supposed to asssume it is, because there are only 10 years of data?
Thanks!
You shouldn’t have to guess; expect that on the real exam it will be clear.
For the given question, I’d assume that the mutual fund’s been around for more than ten years.
In this question, which of the measure of mean should one choose, geometric or arithmetic mean. I do know that geometric mean is more accurate.
The geometric mean is not “more accurate”. It is appropriate for some applications, and the arithmetic mean is appropriate for some applications. You need to know which is better for what.
The geometric mean is appropriate for estimating the long-term growth rate. If they were to ask what the expected growth would be for, say, a period of five years, using the geometric mean (and compounding it for five years) would be the proper approach.
The arithmetic mean is appropriate for estimating a single year’s growth rate. If they were to ask you what the expected growth rate is for the next year, using the arithmetic mean would be the proper approach.
Regarding the quant question: first of all it will be clear if it is a sample or population. And in case if it is not clear, then CFA institute will only give one answer which was calculated either with sample or population. So, when you will calculate lets say with sample and answer is given taking it as population. You will find that there is only one answer closest to your answer (hoping you have calculated it right 
)