Questions tagged [poisson-regression]
Poisson regression is one of a number of regression models for dependent variables that are counts (non-negative integers). A more general model is negative binomial regression. Both have numerous variants.
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Python: Nonlinear Poisson Regression with two independent variables, or something similar like a Random Network? [closed]
I'm looking for a algorithm to use Nonlinear Regression with Poisson for predictive purposes in Python or something similar anyway. I would need something similar to Poisson regression, but with some ...
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What type of regression to use when outcome is integers from 0 to 10
I have an outcome variable that measures "community perception," with responses ranging from $0$ to $10$. For instance, the outcome variable might represent answers to the question: "In ...
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How can I use a variable as a covariate which exists only for specific range for some clusters/groups?
I want to know how to use Poisson GLMMs when we have unequal samples available for different groups/clusters/participants in data.
Imagine a study where each of the 60 participants are given 1000 ...
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Why do the standardized beta values and CIs of a glm poisson regression model not differ from the unstandardized ones (using report function)?
For a specific research question i fitted a generalized linear mixed model using a poisson link function due to the characteristics of my data.
For reporting purposes i used the report package and the ...
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Mixture of two Poisson distributions
I would like to determine the mixing between two Poisson distribution means. I have $N$ observations that are drawn from two Poisson distributions. Each observation is drawn from one of the two ...
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Comparing Age-Adjusted Mortality Rate between 2 groups
Context: I am using national mortality database to compare the mortality of X disease by demographic factors. I divided the county based on social vulnerability scoring into 4 groups (1,2,3,4 based on ...
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GLM (Poisson regression) and Linearity
I understand that an assumption of Poisson regression is a linear relationship between the transformed expected response in terms of the link function and the explanatory variables. Therefore you ...
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Is it possible to estimate the cumulative effect without using distributed lag model?
I am fitting the temperature and mortality data by using conditional Poisson regression. The following formula and data are used:
https://bmcmedresmethodol.biomedcentral.com/articles/10.1186/1471-2288-...
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Predictive Modeling of Overseas Filipino Workers' Average Length of Stay: A Comparison of Linear and Poisson Regression Models
i want to find our average length of stay in months with a discrete values however the number of months in the dataset is up to 60 that we can treat as continuous. I would like to determine when is ...
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Is there a way to set an exposure for a Poisson loss in Catboost?
I'd like to use Catboost for actuarial models (eg claims frequency). Although I see that Poisson loss is an option, I don't see that exposures are directly supported. How do people deal with this?
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Do all GLM models not require equal variance?
I am trying to learn about generalized linear models (GLMs). For example, in a Poisson GLM:
$\text{g}(\mu_i) = \text{log}(\mu_i) = \beta_0 + \beta_1*X1_i$
$E[Y_i|X_i] = \mu_i = \text{exp}(\beta_0 + \...
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How can I perform a comparison of poisson and linear modelling using one dataset?
my y is average length of stay in months however the number of months in dataset is up to 60 so I can treat it as continuous but my main objective is to identify when can i determine it's better to ...
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Is there another model for every model that has it's assumptions invalidated? [duplicate]
For example, I have a scenario where the independence assumption of Poisson regression is invalid. Is there a solution to this? Can I still use the model if I am interested in using it to look at the ...
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Alternative to Poisson regression if independence assumption invalid
does anyone know a suitable alternative to Poisson regression if the independence assumption is invalid? Thanks
A hypothetical example - if two cars crash into each other and they go to the same ...
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Poisson regression to find the busiest hour at an ice cream shop
If I wanted to find the busiest hour at an ice cream shop and I had the counts of the type of ice cream sold per hour per day. Could I use Poisson regression to find the busiest hour and month etc for ...
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In subgroup analysis, some coefficients of predictors are insignificant, if full analysis is preformed, the coefficients of predictors are significant
I have a set of data including information of age groups, education level, and meteorological data from 2000 to 2006.
The dataset was spilt by age groups(65-74,75-84,85+),education level(university or ...
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Solution for Overdispersion in Poisson Regression
I have run poisson regression in SPSS (Generalized Linear Model), where BMI is my IV and length of stay (LOS) in hospital for certain disease is my DV (and it's a count variable).
When I run poisson, ...
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Mixed-Effect Poisson Regression Model without count data
I have gone in circles reading about this for days and still not quite understanding.
I have aggregated data at the state level and by year estimating breast cancer incidence rate per 100 k, mortality ...
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Regression of Purchase Count using Offset Term to Carry Information About Package Size/Count
Hello: I am interested in modelling the purchase rate over time (an integer number of purchases, observed daily, for a number of shoppers) for a collection of 3 different products.
The data look a ...
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Comparing a paired count data
I have a group of patients who are subjected to treatment A. I wish to compare the number of events/patient before and after the treatment. The duration of follow up of before and after therapy is ...
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Comparison of regression coefficients, same y but two different X versions
I've seen versions of this question but not specifically answering the question of a statistical test to compare the beta coefficients for two independent variables (x1, x2) but the same dependent ...
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Interpretation of absolute value of ADE in mediatoin analysis
I'm quite new to mediation analysis and try to understand the results I get. I have a new online shop feature I tested in a randomized field experiment. The treated group sees the new feature and the ...
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Poisson or Negative Binomial regression when within-cluster data follow different distributions
I have count data by group for which I would like to to model the outcome using a random effect for group. I was initially planning on using Poisson regression, but checked if the data are ...
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Between steps for fisher information matrix element using Poisson regression?
I am currently working through some math related to my work, and trying to understand how the individual pieces of the following equations come together for the Fisher information matrix expression (...
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Poisson regression with random effect using pre-post data
I have data on outcomes collected across several clinics. The outcome is an integer indicating days until treatment initiation. Outcome data were collected at baseline and follow up, and are collected ...
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Marginal Effect for Poisson Model
I am using package marginaleffects for calculating the AME of an exposure variable on a count dependent variable. I am hence using Poisson (and Negative Binomial as robustness). The dependent variable ...
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How to calculate the log marginal distribution in Tweedie's formula?
2018 Bayes, oracle Bayes, and empirical Bayes
2021 Empirical Bayes: Concepts and methods
Two modeling strategies for empirical Bayes estimation
2013 Empirical Bayes modeling, computation, and ...
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Need guidance in missing value imputation in count variables
I have a few count variables that are part of a larger dataset (the rest of the variables are either numerical or ordinal). Their distributions can be seen below.
My goal is to impute the missing ...
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How to calculate the sample size when compare rate using Poisson regression?
I have a question regarding the sample size calculation if I want to compare rates using Poisson regression. I want to compare the rate of book A to the rate of book B. The rate of book A is defined ...
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Bayesian Modeling of Pre-Post Study with Counts Including Zeros in Baseline
I'm working with data from a pre-post study examining colony-forming unit (CFU) counts before and after the application of a disinfectant. My primary goal is to model whether there's a negative trend ...
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Which statistical model should I use? Poisson regression with multilevel?
I have a study like this: firstly, select several counties within the U.S., and then select bunches of stores within each country. Based on the stores that selected within each country, I need to ...
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Is it valid to predict excess deaths on data used to fit a Poisson regression model?
I skimmed through a study: Excess Death Rates for Republican and Democratic Registered Voters in Florida and Ohio During the COVID-19 Pandemic that estimates excess death rates of Democrats and ...
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Model diagnostic in GLM
If there is no duplicated observations in each level of covariates, then we cannot use Pearson or deviance residuals. An alternative is to use DARMA residuals in R (where we generate the Ys using the ...
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z-values vs t-values in (generalized) linear models [duplicate]
Why does logistic/poisson regression in R give z-values while linear regression gives t-values in the summary output? In general, z-test is used when the population variance is known, but I am finding ...
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Likelihood ratio test vs p value for Poisson regression
I have a Poisson regression model, from its summary table, I could see the p-value for a certain variable, e.g. gender. Since the p-value is testing the hypothesis whether the coefficient of gender ...
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sklearn PoissonRegressor giving all coefficients zero
I'm doing a random exercise of comparing statsmodels and sklearn regression tools, specifically Poisson Regression (unregularised GLM).
I am trying different libraries on the Insurance dataset from ...
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Poisson fixed effects model in pglm estimating time-invariant predictor
I am analyzing panel data on various municipalities (id_mun) over several years using the pglm package in R. My dataset contains a variable "treatment" which is continuous but is time-...
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How to make predictions with parameters obtained from a zero-inflated Poisson model with Bayesian approach?
I have a dataset with one response variable and one explanatory variable. Here is my zero-inflated Poisson model with a Bayesian approach.
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Poisson regression with small denominators/counts
I have daily data on surgery cancellations for about six months and would like to examine the bivariate associations of several factors and surgery cancellations.
Each day there are variable number of ...
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What type of regression analysis should be used for this combination of count data?
What type of regression would be best suited to do a multiple regression analysis with $E$ as the dependent variable? Is using a binomial regression okay? Thanks for any suggestion.
For each of my ...
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Can we use Poisson regression model to predict the effect of misinformation on user engagement on social media posts
Our research question is what is the effect of misinformation on user engagement on social media posts. The unit of analysis is a social media post. Misinformation is an indicator variable and the ...
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Longitudinal RCT modeling of continuous time
I have data from an intervention study (10 clinics, 5 control, 5 treatment). The outcome is counts, and we have monthly data at baseline, treatment active phase, and post treatment phase. The number ...
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Replicate univariable poisson regression results from a single-row-per-patient dataset on a multiple-row-per-patient dataset
I performed univariable Poisson regression on a dataset of individuals where each individual had one row of data. The variable Sex, for example, had the incidence rate ratio 2.11 (95% CI 1.73-2.56, p&...
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interpreting coefficient of Poisson regression, when dependent variable is a count variable [duplicate]
I have a question about the economic interpretation of Poisson regression.
What is the economic interpretation of the coefficient when the dependent variable is a count variable?
For example, for &...
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How to interpret zero degrees of freedom on residual deviance
I'm wondering how to interpret residual deviance from a Poisson regression on 0 degrees of freedom?
I have a dataframe with count data on events and number of people at risk for the disease, with ten ...
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Recovering hazard rate for interacted Poisson model in R
I am implementing the Wooldridge Two Way Mundlak regression and have an interacted model like so:
...
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ZIGP-Regression for count data/with AR features
assume I have time series count data that come from a zero inflated poisson distribution (ZIGP).
My idea was to estimate a ZIGP-Regression with including AR-features (lagged values) among other ...
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What is the adequate regression model for bounded, continuous but poisson-like data?
I am trying to compare the lodging resistance scores of different wheat cultivars in an agronomic trial. Lodging is the phenomenon in which wheat plant can bend and lean closer to the ground as a ...
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Nb/Poisson regression with weighted survey data resulting in counts with decimals
I am analysing suicide counts and thus it seems appropriate to use Nb/Poisson regression. However, my counts come from survey data and are only whole numbers when unweighted. Once I realise the ...
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Effects of right-censoring on Poisson IRR estimates
I have some time-to-event data with right-censoring.
Details Added: Each subject is followed up until first event (no recurrent events) or loss to follow-up. Let's assume there are no competing risks.
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