Questions tagged [negative-binomial-distribution]
A discrete, univariate distribution modelling the number of ${\rm Bernoulli}(p)$ trial successes until a specified number of failures occur.
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Standard negative binomial regression when counts are mainly zeros?
This question must have been asked many times before but I can't find an answer.
I'm getting very confused about when to use a zero-inflated negative binomial regression vs standard negative binomial ...
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When to choose GAM over GLMM and how to include random effect into GAM
This is a follow-up question to this question.
Here is a description of the dataset: the outcome variable is the number of contacts per participant for two periods before lockdown and under lockdown. ...
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Covariance of multivariate negative binomial with random effects
I am fitting a negative binomial-2 regression model where there is a multivariate normal random effects term. I would like to find an equation for the covariance of two outcomes. In "the ...
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$\min\{X,Y\}$; where $X,Y$ are geometric random variables
Does $\min\{X,Y\}$ follow a geometric distribution? $X \sim BN(1,p); Y \sim BN(1,q)$ independent
$$P(\min\{X,Y \}=k)=P( \min\{X,Y\} \geq k)-P(\min\{X,Y \} \geq k+1)=\sum_{n=k}^{\infty}(1-p)^{n-1}p\...
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Relating animal sightings with land cover - poisson, negative binomial, zero inflated and then LOST
I have a number of sightings of animals in a location (an island). The sightings are opportunistic (corpses people stumble upon) and happen in different land covers. I am supposed to investigate if ...
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Am I using the right method to model my zero-inflated data?
I have a dataset of workplace permits, sample size n=3000. The data is collected between 2012-2020, so if a permit was active some time between 2012-2020, I included it in my analyses. My exposure of ...
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Underdispersion handled with negative binomial distribution? [duplicate]
To get a more flexible model than Poisson regression, one can choose the negative binomial distribution instead for modeling with $E[y] = \mu$ and $Var(y) = \mu + \frac{1}{ \theta} \mu^2$. As a ...
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Calculate combined confidence interval of two variables in a negative binomial model (in R) [closed]
I have a multivariable negative binomial model in R for which I want to combine two variables:
Variable 1: binary variable (no/yes)
Variable 2: continuous variable (0-3)
I want to calculate ...
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Negative Binomial Regression for repeated measures ,daily for one week
I have a dataset of 2,000 subjects, each providing daily social contact data for one week (14,000 observations = 2000 subjects * 7 days). I aim to describe the number of contacts using variables such ...
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Construction of Dirichlet multinomial from independent negative binomials
I have a dataset with ISO3 country code, Year (from 2010 to 2019), Causes of death category (24 categories in total) and number of deaths. The sum of deaths across causes is fixed. My goal is to ...
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biased MLEs in negative binomial models
I found the maximum likelihood parameters of negative binomial models are biased. An example code is provided below. Is this normal? Are there ways to obtain unbiased estimates?
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Visualizing restricted cubic splines in glm.nb
I am trying to visualize the relationship between a continuous variable ("marker") and a count variable ("count") using a negative binomial regression with a restricted cubic ...
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Low VIF in conditional model but high in zero-inflated model
I am using glm ZINB to make models that predict abundance of frogs based on observations from 57 sites. I used the check_model function from the performance package and it shows that the best model ...
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Are there known bounds for the median of a negative binomial distribution based on its parameters?
This seems like an innocent enough question to me, but I could not find a satisfactory answer when I did some digging. The binomial distribution has a closed form median and the Poisson distribution ...
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Am I Doing Things Right? / negative binomial test
I have a dataset consisting of social media comments about a particular context from 1999 to 2024.The topic titles of the comments were annotated into two categorial variables = 0 and 1.
I am aiming ...
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