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Stats help - Linear Model fitting in R

  1. Apr 26, 2010 #1
    I have this residual vs fitted values plot in R, and it should show a scatter of points with constant variance and mean 0. The mean 0 part seems to hold, but there is quite a clear diamond shape for the variance...

    I have tried raising the response variable to a power <1 and a log transformation, along with transforming all of the parameter types but all to no avail.

    Any help would be greatly appreciated. Anyone have any tips as how to try and improve this...

    Thanks

    QpY3Z.png
     
  2. jcsd
  3. May 2, 2010 #2
    How many explanatory variables do you have? What are you trying to model? Are you restricting your intercept to a value of zero? From the clear linear trend in your residual plot, a response transformation will not help your situation. What is the R code that you are using?
     
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