title: Scale back linear regression coefficients in R from scaled and centered data
body: <p>I'm fitting a linear model using OLS and have scaled my regressors with the function scale in R because of the different units of measure between variables. Then, I fit the model using the lm command and get the coefficients of the fitted model. As far as I know the coefficients of the fitted model are not in the same units of the original regressors variables and therefore must be scaled back before they can be interpreted. I have been searching for a direct way to do it by couldn't find anything. Does anyone know how to do that?</p>
  
  <p>Please have a look to the code, could you please help me implementing what you proposed?</p>
  
  <pre><code>library(zoo)
  filename="DataReg4.csv"
  filepath=paste("C:/Reg/",filename, sep="")
  separator=";"
  readfile=read.zoo(filepath, sep=separator, header=T, format = "%m/%d/%Y", dec=".")
  readfile=as.data.frame(readfile)
  str(readfile)
  DF=readfile
  DF=as.data.frame(scale(DF)) 
  fm=lm(USD_EUR~diff_int+GDP_US+Net.exports.Eur,data=DF)
  summary(fm)
  plot(fm)
  </code></pre>
  
  <p>I'm sorry this is the data.</p>
  
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