Some people call such problems "spell" problems.
Others might talk of runs.
Either way, discussions and tools exist. -tsspell- from SSC
and the discussion in
SJ-7-2 dm0029 . . . . . . . . . . . . . . Speaking Stata: Identifying
spells
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . N.
J. Cox
Q2/07 SJ 7(2):249--265 (no
commands)
shows how to handle spells with complete control over
spell specification
apply. See the help file for -tsspell- which includes several examples.
Nick
[email protected]
BW Wheeler
I'm having trouble figuring out a solution to this data management
problem, and have exhausted all books and findit (partly as it's hard to
know what to search for)!
I have time series data captured from accelerometers, with an
observation of 'activity counts' logged every 10 seconds for several
days for each individual. If the number of counts is zero continuously
for any period of 10 minutes or more (i.e. 60+ observations), we need to
assume that the accelerometer was not being worn, and to treat these
zeros as missing.
So, my data look something like this:
Observation Date Time Activity
1 13/05/2006 15:20:00 230
2 13/05/2006 15:20:10 215
3 13/05/2006 15:20:20 0
4 13/05/2006 15:20:30 0
5 13/05/2006 15:20:40 0
...
Does anyone have any ideas of how I can replace the 'Activity' value
with missing, if that value is a zero in the midst of a continuous
series of 60+ zeros?
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
