# Re: st: Has the time trend resulted in a 2/3 reduction between year?? and year ??, can Stata tell you yes or no. (fwd)

 From Daniel Wilde <[email protected]> To [email protected] Subject Re: st: Has the time trend resulted in a 2/3 reduction between year?? and year ??, can Stata tell you yes or no. (fwd) Date Fri, 18 Jan 2008 18:18:22 +0000

Austin,

Thanks greatly for you help. I'll try your code out. I'd be interested to hear your reservations about my method if you have the time and inclination. They may concern something I have already considered, but then again, they may not.

Kind Regards,

Daniel Wilde

--On 18 January 2008 12:37 -0500 Austin Nichols <[email protected]> wrote:

```Daniel Wilde <[email protected]>:
Something is wrong with your mail server or client software.  Both of
these messages appear to have been sent within one second of each
other, as you can see at:
http://www.stata.com/statalist/archive/2008-01/

You can do all this within Stata, though it is not clear to me that it
is a good idea.  Try this (untested) approach for starters:

g a=.
g b=.
g p=.
levelsof country, loc(c)
foreach i of local c {
qui reg data301 time if country==`i'
replace p=2*ttail(e(df_r),abs(_b[time]/_se[time]))  if country==`i'
su time if time==1990 & e(sample), meanonly
if r(N)==0 {
replace time=1990  if country==`i'
predict A  if country==`i'
}
else g A=data301 if country==`i'
replace time=2015 if country==`i'
predict B if country==`i'
replace a=A  if country==`i'
replace b=B  if country==`i'
drop A B
}
bys country: drop if _n>1
keep country p a b
g c="no significant trend" if p>0.1
replace c="significant upward trend" if b>a & p< 0.1
replace c="significant downward trend" if b<a & p< 0.1 & b > a/3
replace c="achieved 2/3 reduction" if p<.1 & b < a/3
list, noo clean

On Jan 18, 2008 9:10 AM, Daniel Wilde <[email protected]> wrote:
```
```All,

I just thought I would repost the below message because I didn't get any
responses yesterday. Is there anything about it that's unclear? Or is it
just a boring question?

Kind Regards,

Daniel Wilde

------------ Forwarded Message ------------
Date: 16 January 2008 19:37 +0000
From: Daniel Wilde <[email protected]>
To: [email protected]
Subject: Has the time trend resulted in a 2/3 reduction between year ??
and year ??, can Stata tell you yes or no.

```
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