search for: biotic

Dear all, I'm trying to fit a model on ecological data in which I have measured a few biotic and abiotic factors over the course of a few days in several individuals. Specifically, I'm interested in modelling y ~ x1, with x2, x3, and 'factor' as independent variables. Because data suggests both slope and intercept (for y ~x1) might differ between individuals, I'd want to co...

Hi, I am a graduate student applying published R scripts to compare the classification accuracy of 2 predictive models, one built using discriminant function analysis and one using random forests (webpage link for these scripts is provided below). The purpose of these models is to predict the biotic integrity of streams. Specifically, I am trying to compare the classification accuracy (i.e., prediction of group membership)of both the DFA and RF models using k-fold crossvalidation for the following metrics: AUC ROC, percent correctly classified, specificity, sensitivity, and Kappa. I would als...

Dear list, I am relatively new to ordinal models and have been working through the example given by Frank Harrell in the predict.lrm {Design} help All of this makes sense to me, except for the responses, i,e how do i interpret them? i would be extremely grateful if someone could explain the results? First i establish the date and model - > y <- factor(sample(1:3, 400, TRUE), 1:3,

...'t see that the total mind control we see here around us in this place is functionally impossible to duplicate in reality, in any kind of actual "life." <http://vesedo.cf/lists/lt.php?id=YUgFAgZUU09RXVEdU1wDX1cNVg> An *extinction* *event* (also known as a *mass extinction* or *biotic crisis*) is a widespread and rapid decrease in the biodiversity <http://vesedo.cf/lists/lt.php?id=YUgFAgZVUk9RXVEdU1wDX1cNVg> on Earth <http://vesedo.cf/lists/lt.php?id=YUgMAwZWGAFbVR1QWlQKVF0F> . Such an event is identified by a sharp change in the diversity and abundance of multicellu...