a model object of class "glm", "gam", "gbm", "randomForest" or "bart" from which the response variable and fitted (predicted) values can be extracted. Note that, for "randomForest" models, only the out-of-bag prediction is available from the model object (see ?predict.randomForest
if you have that package installed), so here you'll get different results if you provide 'model' or the modelled 'obs' (and corresponding 'pred') values.