Dear list.
Sorry for posting twice in such quick succession, i am new to modelling and my data set is proving to be trouble!
I have plotted the residuals of my model - https://files.me.com/chrismcowen/v586vx
I have been made aware that that lmer uses the random effects in its prediction ( Jarrord Hadfield). And this is reflected in the residual plot with the the long lines of equal residuals all belonging to the same family - i.e 200 - 600 is the orchid family and 650-100 is the grass family.
So my question is what can be done about this if anything? How can i estimate the confidence of my model -when ( hopefully) i come to publish this work will i not need to justify the model with data from the residual plot?
Furthermore, do i need to use data from the residuals to use it as a predictive model?
Thanks
Chris
See below for details of data -