115k views

### Does an unbalanced sample matter when doing logistic regression?

Okay, so I think I have a decent enough sample, taking into account the 20:1 rule of thumb: a fairly large sample (N=374) for a total of 7 candidate predictor variables. My problem is the following: ...
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### What is a "saturated" model?

What is meant when we say we have a saturated model?
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### Logistic regression in R resulted in perfect separation (Hauck-Donner phenomenon). Now what? [duplicate]

I'm trying to predict a binary outcome using 50 continuous explanatory variables (the range of most of the variables is $-\infty$ to $\infty$). My data set has almost 24,000 rows. When I run ...
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### Can I fit logistic regression over a dataset with only categorical data?

I have a dataset which contains only categorical data i.e.A,B,C,D (like factors) for each predictor. There are 10 predictors and the dependent variable is binary, <...
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### Rare Events Logistic Regression

Suppose the event of interest occurs in approximately $10 \%$ of the cases where the number of cases is around $5,000$. Should you use a penalized logistic regression for this or is regular logistic ...
78 views

### Is there a way to increase the number of predictor in a logistic regression when sample size is small?

One of the dependent variables in my dataset is a binomial variable indicating whether an invasive species has been eradicated (with $n_{1}$ = 23) or not (with $n_{0}$ = 75) after the use of a certain ...
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470 views

### Logistic regression with small number of cases

The project I'm working on attempts to explain why an NGO is present (1=present,0=not present) in some countries (15) but not others. As I'm working with country-level data, my sample size is ...
426 views

### Feature selection and PCA in logistic regression with rare events data

I am working on a census-related project where I am interested in assigning to everyone a score that estimates the probability they will have a demographic characteristic of interest. In this case, ...
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1 vote
4k views

### R - Model selection in Glmer

Having troubles to perform a model selection for glmer in R. I'm using the package lme4 with the following structure: ...
1 vote
84 views

### Logistic regression with rare events [duplicate]

Could somebody provide some references on the application of logistic regression for modelling rare events? So far I've come across three methods with the main references below: Exact logistic ...
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