All Questions
6 questions
25
votes
3
answers
9k
views
Can a model for non-negative data with clumping at zeros (Tweedie GLM, zero-inflated GLM, etc.) predict exact zeros?
A Tweedie distribution can model skewed data with a point mass at zero when the parameter $p$ (exponent in the mean-variance relationship) is between 1 and 2.
Similarly a zero-inflated (whether ...
- 1,781
9
votes
2
answers
24k
views
SE of fit versus SE of prediction
I would like to get the standard error on a prediction. Using R glm, I can get the SE of the fit for a specific prediction:
...
- 435
7
votes
0
answers
9k
views
Prediction with CI - predict.glm doesn't have interval option [closed]
I have a model and a graph:
n1 = glm(formula = cbind(ml, ad) ~ x1, family = "quasibinomial")
plot(x1, ml/(ml+ad))
And I would like to plot a predicted line with ...
- 6,187
6
votes
3
answers
7k
views
How to specify/restrict the sign of coefficients in a GLM or similar model in R
The situation: I'm struggling with a predictive analysis of food sales prices using a generalized linear model. My dataset contains different kinds of food (cheeses, vegetables, meats, spices etc.) ...
- 603
5
votes
1
answer
6k
views
How to use a GAM to predict the probability in binomial data as a function of predictors
I'd like to predict the probability of success as an unknown function of predictor variables. For example, consider the following fake data
...
- 516
1
vote
2
answers
735
views
Logistic regression and prediction
I'm following this tutorial to fit a logistic regression model on to my data which has a binary response. I've understood the reasoning behind each step, apart from why the author checks the first 5 ...
- 209