Hi,

I need to calculate stock volatility using CRSP daily stock returns. According to the article, it is calculated using the square root of the sum of squared daily returns over the year. To adjust for differences in the number of trading days, the raw sum is multiplied by 252 and divided by the number of trading days. I have the variable "returns". Does anyone which code to use for this?

Another thing: the CRSP data was too big to download at once, so I need to merge. However, when I try to merge, it gives the error: factor-variable and time-series operators not allowed. What should I do?

Thanks in advance!