An averaged model based on Quartile and Mean of Quartiles

On May 21, 2016, at 7:41 AM, ch.elahe via R-help <r-help at r-project.org> wrote:

Hi all,

Here is my df and I want to make an averaged model of my variables based on Time like the following:


  $ Protocol   : Factor w/ 48 levels "DP FS QTSE SAG",..: 2 3 43 42 
  $ Time       : num  182 185 189 234 186 ... 

  $ Systemtype   : Factor w/ 2 levels "Aera XJ","AERA XQ": 1 1 1 
  $ ADJ        : Factor w/ 2 levels "auto","manu": 1 1 
  $ BR         : int  384 384 384 384 512 384
  $ TF         : int  10 10 13 7 7 5 5 
I split my df into quartiles for time,


  df$quant=findInterval(df$Time, quantile(df$Time), rightmost.closed=TRUE)
by the column df$quant I see quartiles 1 to 4 for time, next I want to create a new column for example for BR and if df$quant==1 then put mean of first quartile of BR in that,if df$quant==2 put mean of second quartile of BR in that and so on. I do the same for every numeric variable. Does anyone know how to that?

On May 21, 2016, at 7:41 AM, ch.elahe via R-help <r-help at r-project.org>

wrote:

Hi all,

Here is my df and I want to make an averaged model of my variables based

on Time like the following:

  $ Protocol   : Factor w/ 48 levels "DP FS QTSE SAG",..: 2 3 43 42
  $ Time       : num  182 185 189 234 186 ...

  $ Systemtype   : Factor w/ 2 levels "Aera XJ","AERA XQ": 1 1 1
  $ ADJ        : Factor w/ 2 levels "auto","manu": 1 1
  $ BR         : int  384 384 384 384 512 384
  $ TF         : int  10 10 13 7 7 5 5
I split my df into quartiles for time,


  df$quant=findInterval(df$Time, quantile(df$Time),

rightmost.closed=TRUE)

by the column df$quant I see quartiles 1 to 4 for time, next I want to

create a new column for example for BR and if df$quant==1 then put mean of
first quartile of BR in that,if df$quant==2 put mean of second quartile of
BR in that and so on. I do the same for every numeric variable. Does anyone
know how to that?

Perhaps, but untested in the absence of a reproducible example and
choosing to instead use a name for the dataframe which is not also a
function name:

aggregate( dfrm[ , sapply( dfrm, inherits, "numeric")],   # logical
indexing for `[, j]`
           dfrm['quant']      # using "[" keeps it a list
           mean)

--

David Winsemius
Alameda, CA, USA