Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: st: calculating the difference in logs
From
Nick Cox <[email protected]>
To
"[email protected]" <[email protected]>
Subject
Re: st: calculating the difference in logs
Date
Thu, 12 Jul 2012 14:00:08 +0100
Time series operators work on variables, not expressions in general,
so I don't think there is a short-cut of the kind you seek.
Nick
On 12 Jul 2012, at 13:47, "Data Analytics Corp." <[email protected]
> wrote:
Hi,
Suppose I have a time series on annual sales. I'd like to calculate
the year-over-year percent change using the difference in the
natural logs. I tried
g pct = d.ln(sales)
but I got an error message "unknown function d.ln()"
Then I tried
g logg = ln(sales)
g pct = d.logg
and I got the right answer. I'd like to use just the one line
statement as in the first example. Can this be done?
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/