Questions tagged [link-function]
A transformation of a parameter governing a response distribution that is used as a crucial part of the generalized linear model to map that parameter's range (which may be from 0 to 1, or only positive values, e.g.) to the real number line $(-\infty, +\infty)$.
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How do you visualise the conditional esperance of your outcome variable depending on the predictor?
I've read several posts regarding the choice of distributions and link functions for GLMs. Although I'm far from understanding it all, what I've gathered is that the purpose of the link function is to ...
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Handling Non-normality of Reaction Time Data in Mixed Models
I am examining the effect of 'Phase' on reactions time (RT) data using a mixed model in lme4.
However, as is common with RT data, the residuals are non-normal.
This is the first model, which is a ...
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GLM link function, variance Function, and dispersion for linear regression
we were recently introduced in class to GLM's and I am still trying to wrap my head around link functions, variance functions and dispersion paramters. In particular we were asked re-write the linear ...
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Link function for exponential regression
I have a dataset with an exponential relationship that I'm linearizing before fitting with code like this:
glm(log(y) ~ log(x), family = gaussian)
I'm trying to ...
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Custom link function for logistic regression model
I am trying to build a generalized linear model with a custom link function. This is a follow up to this question: Understand and specify a generalized logistic model in R
In this paper A Generalized ...
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Understand and specify a generalized logistic model in R
I am reading a paper in which the authors models tree survival (mortality). They go and remeasure tagged trees for decades to establish "survival functions" for the given tree species and ...
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Residuals assumptions in glmm not verified! Help
I am trying out GLMMs models to test whether two categorical variables (species and sex) and their interaction (sex + species + sex*species= fixed factors) influence certain acoustic parameters (...
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Predicted probabilities from logistic vs log-binomial model
I am giving a talk on logistic regression and I was going to mention log-binomial models to estimate risk-ratios. I understand the difference between odds and probabilities and that they only converge ...
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Is there a link function $g$ which is a monotonic function with $g(0) = 0$? [closed]
I am working on a machine learning project (similar to this paper https://arxiv.org/abs/1912.04136). For this I need to make an assumption that a link function is monotonic and takes value $0$ at $0$. ...
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Can expected variance of GLM be expressed through gradients under non-cannonical link functions?
In GLMs (generalized linear models), one can typically obtain an estimate of the expected variance of the response variable given the predictors as a transformation of the same parameter that defines ...
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How to model suspected piecewise-linear data with a lasso GLM
My data consist ~130 observations. Each observation has several thousand features (including many collinear or otherwise useless features) and a position along a single spatial dimension. Some sets of ...
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meaning of this GLM defintion
The answer key says "Different link functions have different shapes and can therefore fit to different nonlinear relationships between the predictors and the target variable."
Shouldn't we ...
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Extremely small confidence intervals and standard deviations in a clmm-model
I have a data set with an effort rating (varying in an ordinal scale from 1 to 7) as the response variable and a time point of measure (seven consecutive measures) as a fixed factor. An individual is ...
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Use a GLM/GAM model with Gamma family & identity link despite warning?
What I have tried and done so far:
I am running GLMs and GAMs on my positive, continuous response variable.
I have determined that the Gamma distribution would fit my data best by plotting various QQ ...
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Coding error? Why is the treatment not showing as a significant effect with GLM and standard error is so high?
I've been handed off some data to analyze and I'm looking for
something simple and straightforward. The main study question is
testing the efficacy of 7 herbicides, with one untreated control. The
1 ...
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