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I have a question concerning the output of a “dredge” function of the “MuMIn” package in R. I am trying to build a model with ecological variables that best explain my species occupancy data for 41 sites in the field (which I have gathered from camera traps). For this particular run I have preselected two variables that could explain my occupancy (“Palm” and “Grassland”) and I have put in some variables that could affect detection. The output of the first 10 models of the dredge are shown below:

enter image description here Just to see if I understand my output correctly: I cannot distinguish between the top 9 models (because the delta value is <2)? Most of my top models will not include either “Grassland” or “Palm” as variables explaining my occupancy data, meaning that they are bad predictors?

What exactly do the adjR^2 and weight values mean?

Thanks a lot!

kjetil b halvorsen
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Fleur
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    This is the documentation of the output ‘model selection object’ https://www.rdocumentation.org/packages/MuMIn/versions/1.43.15/topics/model.selection.object. See more details in Johnson and Omland 2004 “model selection in ecology and evolution” https://www.sciencedirect.com/science/article/abs/pii/S0169534703003458 – David LeBauer Jan 25 '20 at 22:45
  • Please type your question as text, do not just post a photograph or screenshot (see [here](https://stats.meta.stackexchange.com/a/3176/)). – gung - Reinstate Monica Jan 26 '20 at 00:35
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    You'd do best to not do this. *Dredge*, in the name of the function, is not a complement. This is not a good way to determine which variables are relevant. It may help you to read my answer here: [Algorithms for automatic model selection](https://stats.stackexchange.com/a/20856/7290). – gung - Reinstate Monica Jan 26 '20 at 00:39

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