# All Questions

194,248 questions
Filter by
Sorted by
Tagged with
8 views

78 views
+100

### Optimize classification rule in multinomial logistic regression

We know that in the case of logistic regression, a classification threshold p=0.5 is generally not an optimal choice when seeking to optimise sensitivity and specificity. This is generally due to the ...
4 views

### SUR regression gets error "LU computationally singular: ratio of extreme...": can work around but still concerned about error margins

I originally posted this to stackoverflow, and was advised by I_O that the question would be appreciated more here. I am not sure how to reformat this to be appropriate here, so I am copying it over ...
6 views

### How can the power of a clinical trial be estimated mid-recruitment?

For my PhD I started a three-arm, clinical trial which due to the pandemic I have to stop after having recruited 69 participants instead of 150 originally calculated to give a power of 80%. The trial ...
9 views

### Adding independent variables to mixed effects model and controlling for interaction

I have formed 2 separate mixed effects models to see how these variables affect "chance" (this is risk taking behavior): ...
4 views

### Why do permutation importances for my model all zeros?

I really am at a loss here. I have several tree-based binary classification models trained on a balanced dataset of ~300 samples and ~15000 features. The models have AUROC around 0.8. I want to ...
1 vote
27 views

1 vote
9 views

### Selecting a test to prove that the observed changes in the performance of two machine learning models are statistically significant

I have developed two machine learning models which I evaluated with two different datasets. My initial hypothesis was that their performance would be higher in dataset 2 as compared to dataset 1. ...
12 views

### Autocorrelation of residuals

I am working with R and I got the following residuals in time series. But I have problem determine if the are autocorrelated or not. Any help?
2k views

### How to do likelihood ratio test to compare two panel models (plm) in R

I have a problem to run a likelihood ratio test to compare two panel regression models in order to find whether one model is significantly better than the another one. However, neither lrtest nor ...
9 views

### Learning Algorithm Time & Sample Complexity

Let $X=R^{2}$. Let $u=\left(\frac{\sqrt{3}}{2},-\frac{1}{2}\right),\ w=\left(-\frac{\sqrt{3}}{2},-\frac{1}{2}\right),\ v=\left(0,1\right)$ and \$C=H=\left\{h\left(r\right)=\left\{\left(x_{1},x_{2\ }\...