标题: sample or population [打印本页] 作者: busprof 时间: 2011-7-13 16:14 标题: sample or population
in 5 year period the annual return on an investment are 5%,-3%,-4%,2% and 6% the standard deviation on this investment closest to
A.4.0%
B.4.5%
C.20.7%
If i consider it is sample --> Sd (sample) =4.5%
If i consider it is population -->Sd(population)=4%
Which one is correct answer
I think in 5 year period of annual return is population
could you please clarify it for me作者: ishfaque 时间: 2011-7-13 16:14
It's always population unless otherwise stated..作者: koba 时间: 2011-7-13 16:14
Question #4 page 163 book 4 Schweser --> correct answer is B calculate as sample
it make me confused作者: dmar 时间: 2011-7-13 16:14
Well I think I misunderstood the question. Here it says "in 5 year period the annual return on an investment" which implies that return is not only for 5 years, it could be for more years. However, if it is mentioned like "annual returns on 5 years investment" and 5 observations are given, then that is a population.
Previous comment was very general with respect to sample and population that if only data sets are given then that's a population unless otherwise stated.作者: Finalnub 时间: 2011-7-13 16:14
I guess since we only have data of 5 years of return, it's more reasonable to presume this is a sample from a population of historical return.
Still, I agree that this question is sort of misleading
