[R] R-help Time Series

(Ted Harding) Ted.Harding at nessie.mcc.ac.uk
Sat Feb 26 13:06:29 CET 2005


On 26-Feb-05 Prof Brian Ripley wrote:
> I think
> 
> 1) You have the units wrong: these appear to be the figures
> quoted for KB of compressed files, and the compression is
> nothing like 1024:1.

Sorry, yes, you are correct: it is KB and not MB (a slip of the
eye on my part).

> 2) This is not `a series' unless you add a time base, e.g. via
> a call to ts().

Well, in R terms that is strictly correct; but a sequence of
data corresponding to successive regular time points is usually
described as a "time series"!

> Surely subscribers are aware that they do not get many MB/day
> and that extrapolation to that level is just speculation.

Granted (see above). But anyway, this sort of thing is not
the real point, which is that (regardless of units) this
'sequence' of data has interesting features (which prompted
me to submit my somewhat tongue-in-cheek posting).

The original (quoted below) now suitably amended.

> On Sat, 26 Feb 2005 Ted.Harding at nessie.mcc.ac.uk wrote:
> 
>> Hi Folks,
>>
>> While I was browsing in the R-help archives yesterday,
>> I got curious about the time series of the sizes of
>> the monthly archives in KB [was MB].
>>
>> This turned out to have an unexpected feature or two,
>> which I leave to readers to explore for themselves.
>>
>> I'm now wondering at what point in time we might expect
>> to be receiving 1000KB/month (30+KB/day) [was MB]. It's
>> not that far away, it seems, but there are a couple of
>> interesting modelling questions behind it.
>>
>> In particular, I wonder by what mechanism the numbers
>> grow, according to the law which the data seem to indicate.
>>
>> Over to you.
>>
>> (just my 0.001 MB worth ... excluding headers)
>>
>> Ted
>>
>> To save you the trouble, the following sets up the
>> sequence [was series; and MB]:
>>
 KB<-c(55,19,19,18,19,17,35,27,47,
 55,32,50,55,41,49,50,28,53,42,81,54,
 99,60,84,80,76,75,78,61,83,97,141,122,
 96,144,173,153,226,202,131,165,183,175,168,187,
 240,272,262,195,236,244,285,249,326,345,392,268,
 455,320,418,453,468,422,447,400,323,516,478,327,
 450,487,535,658,573,606,659,543,655,722,677,567,
 519,703,886,793,719,816,812,730,698,831,969,736,
 855)
>>
>> April 1997 -- January 2005
>>
>> --------------------------------------------------------------------
>> E-Mail: (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk>
>> Fax-to-email: +44 (0)870 094 0861
>> Date: 26-Feb-05                                       Time: 10:31:05
>> ------------------------------ XFMail ------------------------------
>>
>> ______________________________________________
>> R-help at stat.math.ethz.ch mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide!
>> http://www.R-project.org/posting-guide.html
>>
> 
> -- 
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595


--------------------------------------------------------------------
E-Mail: (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk>
Fax-to-email: +44 (0)870 094 0861
Date: 26-Feb-05                                       Time: 12:06:29
------------------------------ XFMail ------------------------------




More information about the R-help mailing list