|Author||Topic: Std deviation and Std error|
|I' having issues with reading 9 question 11, in level one. The question stipulates as below -
"Basing your estimate of future-period monthly return parameters on the sample mean and standard deviation for the period January 1994 to December 1996, construct a 90 percent confidence interval for the monthly return on a large-cap blend fund. Assume fund returns are normally distributed."
There is a table that proceeds this with the relevant data. The solution uses the standard deviation instead of the standard error in the calculating the confidence interval - Despite this being a sample! I would, really, really appreciate if someone could elaborate on why they use standard deviation instead of standard error.
As far as I can tell this is the opposite logic, compared to answers shown in later readings such as practice problem 3b, reading 10. Please help, thanks in advance.