Page 1 of 1
Rolling VaR estimates
Posted: Sun Aug 11, 2013 7:51 am
by Stu
.
Re: Rolling VaR estimates
Posted: Sun Aug 11, 2013 4:16 pm
by Stu
。
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 2:30 am
by trubador
Suppose you have a return series called rt. Then, for EWMA you can try:
Code: Select all
!alpha = 0.02 'you should provide an appropriate value for this parameter
smooth(s,!alpha) rt^2 ewma
And as for GJR with t-distribution:
Finally, to obtain the lower %1 quantile of a series y:
Please note that, all these commands (and many more) are available in the users guide.
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 7:25 am
by Stu
.
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 8:34 am
by Stu
I run the programs, but it keeps showing up error messages. And have tried to adpat the codes, but couldnt figure out what the problem is!!
Could someone please help, by perhaps even giving some hints at the problems? I very much appreciate your time!
Thanks.
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 9:40 am
by Stu
。
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 9:51 am
by Stu
。
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 10:41 am
by EViews Gareth
Code: Select all
%smpl = @str(!i) + " 1250"
scalar x = @elem(ewma, %smpl)
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 11:05 am
by Stu
Gareth,
When i run it, it shows up 'Illegal date 1 1250 in “scalar x = @elem(ewma, "1 1250")"
What could be the problem here?
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 11:07 am
by EViews Gareth
Sorry, I posted without thinking.
I don't understand what you're trying to do with that line. @elem takes a single date, not a range of dates.
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 11:13 am
by Stu
。
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 12:51 pm
by Stu
。
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 1:04 pm
by EViews Gareth
Re: Rolling VaR estimates
Posted: Mon Aug 12, 2013 1:13 pm
by Stu
.
Re: Rolling VaR estimates
Posted: Tue Aug 13, 2013 1:23 am
by trubador
I tried to modify your code so as to perform what you want and to give you the idea for further adjustments. However, I suggest you to go over
An Introduction to Eviews Programming before moving forward.
Code: Select all
!window = 1250
!length = @obsrange
!alpha = 1-0.94 '1-alpha is the coefficient of estimated variance
!scale = 10000 'it might be a good idea to adjust the scale
series x 'create the output series beforehand
matrix(!window,!length) results 'you can create a matrix to store all the resulting smoothed series
' move sample !step obs at a time
for !i = 1 to !length-!window
smpl @first+!i-1 @first+!i+!window-2
smooth(s,!alpha) !scale*returns^2 ewma
stom(ewma,ewmat) 'convert series to a vector
colplace(results,ewmat,!i) 'place the vector into the matrix
x(!window+!i) = ewma(!window+!i)
next
smpl @all