When I try to export in pdf a R Markdown file I get the following mistake:
! Missing { inserted. <to be read again>
The concerned line is this one:
$$
AIC = ln \hat{\sigma}^{2}_\hat{u_t} + \frac{2n_k}{T}
$$
I do not get what is wrong with the way I structure the formula. FYI when I export in .doc it works fine, so all the problems start when I try no knit on pdf!
Anyone has suggestions??
It's having trouble with your complicated subscript,
\hat{u_t}-- try enclosing that entire term in{ }.