Stands for Generalized Estimating Equations which is an approach to estimating regression coefficients. GEE can be used on clustered / longitudinal data and has the attractive property that it provides consistent estimators of regression coefficients and unbiased inference even when the association ...

learn more… | top users | synonyms

0
votes
0answers
5 views

General question about generating data, using GEE and testing the results

I am new to GEE and try to understand it by using it. Now I have troubles to understand how the "gee" package in R works. I start by explaining what I intended to generate and what my questions are. ...
0
votes
0answers
8 views

Investigation of X on time 1 has an influence on the change of Y between time 1 and time 2

I would like to investigate if X on time 1 has an influence on the change of Y (= absenteeism) between time 1 and time 2: does X on time 1 increases or decreases Y on time 2 controlled for Y on time ...
1
vote
0answers
14 views

How does GEE (Generalized Estimating Equation) treat different cluster size?

I have a population of 200, 000+ patients and their hospital visit information. I'm trying to see if having a certain disease would have an effect on whether they will have readmission or not (this is ...
2
votes
0answers
9 views

GEE Logistic Model with Subject Specific Predictions?

I have fit a marginal logistic model or GEE Logistic Regression model using SAS' proc genmod to obtain estimated parameters associated with mortality (death). Using SAS, I am able to obtain ...
0
votes
0answers
10 views

GEE model with more x time points than y?

I have a dataset that measures a bunch of variables on mothers starting before the baby is born (two time points), and continues to measure them once the baby is born (3 time points). Once the baby is ...
2
votes
1answer
79 views

What does id (cluster) mean in gee?

I wanted to use poisson glm model which would take serial correlation (AR-1) and overdispersion into account. I was directed to use gee, but ...
0
votes
0answers
19 views

Using QIC in glm (geeglm) when there is a warning of glm.fit: fitted probabilities numerically 0 or 1 occurred

I am using geepack in R to look for the best model for my data. I run the gee function with family=binomial(link="logit"). From the results I use QIC to find the ...
0
votes
0answers
15 views

Use clustered S.E. or FE/RE for binary data in an experimental within-subject design?

I am analyzing a 2x2 experimental within-subjects-design, i.e. I have data from all subjects for all four possible treatment combinations. Lets say treatment X has states X1 and X2 and treatment Y ...
0
votes
0answers
14 views

longitudinal data with changing skew over time

I want to examine a group by time interaction in a pre-post treatment study. Initially, symptoms are high so the skew is positive. But at the end of treatment the symptoms are low, so the distribution ...
0
votes
0answers
30 views

Large samples and the p-values almost zero in GEE models

I’m trying to find correlations between some environmental variables and a binary variable, berried/not berried females (rock lobster). I have 20 years of data that were sampled on a daily basis, ...
0
votes
1answer
56 views

General estimating equation with zero-inflated continuous data in R

I'm running a General Estimating Equation using the geepack package in R. I'm wondering what distribution family would be appropriate for my data, which are zero-inflated and continuous. I would have ...
1
vote
0answers
21 views

What is the appropriate link fucntion in GEE for longitudinal data where distribution changes in time?

I'm modeling treatment outcome data in a GEE with Group, Time, and their interaction. At baseline everyone is highly symptomatic, thus the distribution is negatively skewed. At follow up most people ...
0
votes
0answers
20 views

Generalized Estimating Equations with independance correlations structure versus quasi-approach versus negative binomial glm

I would like to know when it is appropriate to use a GEE with an independence working correlation structure, particularly in regard to a data set I am analysing. I have data on pollinator visits, ...
2
votes
0answers
33 views

Specifying distribution in generalized estimating equation GEE

GEE allows you to identify the distribution of the outcome variable and appropriate link function. How do you make this selection in a longitudinal model where the distribution changes in time. An ...
1
vote
0answers
19 views

Modeling change over time when response variable has different range and variance?

Some background: I am working with data from a large cohort study. My outcome is a measure of fine motor skills, and was adapted from a psychometrically validated instrument (the short version ...
0
votes
0answers
30 views

How to analyze nested, repeated and unbalanced questionnaires where the outcome is binary?

Background: My data was collected once a year for 6 years using the same questionnaire. All responses have a person-specific ID. 18 554 responses from 5 654 unique persons were collected from 7 ...
0
votes
0answers
47 views

Score test or tests based on empirical standard error estimates in Logistic Marginal Model?

I am trying to figure out whether to use a score test the other test (I think it's a test based on empirical standard error estimates?) when looking for the effect of a continuous variable in a ...
1
vote
0answers
29 views

How are complex sample analysis and GEE different from each other?

I am currently analyzing a national survey data. The survey design is complex: 1) strata 2) cluster 3) 2-stage, 4) sampling weight. There are strata; PSUs(agencies) were selected randomly and ...
0
votes
0answers
25 views

Generalized Estimating Equations- How many predictor variables are too many based on sample size?

I am conducting analyses on wild animals, on how diet of an individual changes based on environmental changes. I will list the setup of my dataset below. Until now, I have been running independent ...
1
vote
1answer
47 views

GEE/Mixed model can i use time as a factor variable?

I have data on a compound measured on 1) 0 min, 2) 10min, 3) 60min, 4) 1day and 5) 2months. i have coded these time points as 1,2,3,4 and 5, the compound has a cubic function in time when modeled on ...
0
votes
0answers
29 views

geeglm not recognizing clusters

I am fitting a geeglm model and it is not recognizing the clustering. my model is ...
1
vote
0answers
77 views

GEE as alternative for Linear Mixed Models

A linear mixed model requires the residuals to be normal. In the case of a simple linear mixed model with a random intercept only, a colleague of mine was arguiing that I could just use a GEE with an ...
0
votes
0answers
44 views

Graphing GEE Models in R?

I am currently working on a biological dataset where I am attempting to fit a detection function (Detection probability as a function of distance). I have been using the package geepack (in R-studio) ...
0
votes
1answer
38 views

covariance matrix of residuals from a fitted model to decorrelate residuals

I fit a geeglm model with clustered data and now I would like to decorrelate the residuals of the model in order to run model diagnostics. I read that if I can obtain the covariance matrix of the ...
0
votes
0answers
44 views

geeglm Model matrix is rank deficient after scaling the predictors?

Trying to run a linear regression with repeated measure using geeglm. Here is my original model: ...
0
votes
0answers
91 views

What to use when chi-square independence assumption is violated

I'm trying to describe the characteristics of the sexual partners of each participant. There are multiple partners per participant. All of the variables in my analysis are categorical, so originally I ...
0
votes
0answers
74 views

GEE and post hoc comparisons

I am trying to analyze a dataset using the GEE. This is what I have so far ...
0
votes
0answers
84 views

GEE with exchangeable working covariance vs. GLM and using Clustered Robust standard errors?

I'm analysing a dataset including 100 individuals. These 100 individuals provided self-reported depression sores on equally spaced 4 occasions (every three months). The main independent outcome is ...
0
votes
1answer
110 views

Can someone look at my method for fitting a GEE to my data?

I’ve been doing some statistical analyses in R on some data. It’s for use in a manuscript I’m hoping to get published in a biological journal. Unfortunately, the tests I ended up having to run are ...
0
votes
0answers
29 views

Contradictory results in GEE with or without a covariate

Three independent variables, one is between-group with 2 levels, the other two are within-group with 2 and 4 levels respectively. Another continuous variable (IQ) is controlled as a covariate. The ...
1
vote
0answers
65 views

GEE model for repeated skewed outcome and group mean centered time varying covariates

I have used GEE approach (log link with gamma distribution) to explore factors that are associated with outcomes of interest. My primary outcome of interest is highly skewed costs associated with an ...
0
votes
0answers
153 views

GEE in SPSS: the case of ever-decreasing QICc values

I've been using GEEs in SPSS 22 to analyze my dissertation data and have discovered an interesting problem: when trying to figure out which subset of model factors have the lowest QICc, and therefore ...
1
vote
0answers
109 views

geepack: parameter estimates change sign depending on correlation structure

I'm working on a dataset with the following variables: ...
0
votes
0answers
30 views

GEE Repeated Measurements: Specifying Measurement ID

Say I have 10 subjects, coming from three groups. In each subject I make two measurements (one on the left, one on the right). ...
2
votes
3answers
82 views

How to analyze this messy design?

I need to analyze a data-set, with a very messy design, I am not sure how. I will try to make it simple. A new kind of stitches was invented, and is tested vs. 2 old kind of stitches. I will call ...
1
vote
1answer
90 views

Cluster size in generalized estimation equation (GEE)

I'm using the gee() function from the gee package in R. The problem I'm having is that the 'Maximum cluster size' that I get ...
0
votes
0answers
25 views

How to do and interpret a generalized estimating equation

My study is looking at the effects of enclosure type (1 IV (penned v not penned)) on the stereotypical behaviours and interactions (2 DV's (counts)) of elephants, however using rain (yes/no) and high ...
0
votes
2answers
313 views

Multinomial logistic regression with geepack in R

I am working on fitting a GEE model to a multinomial logistic outcome using the R package geepack. My understanding is that the package uses ...
0
votes
0answers
84 views

Can use an interaction between time and Time-varying-covariate in mixed model or GEE?

I have a data like this: Subjects Y Day X ID1 30 0 0 ID1 40 1 0 ID1 60 2 1 ID1 70 3 0 ID2 20 0 0 ID2 40 1 1 ID2 50 ...
2
votes
1answer
638 views

How can I estimate model predicted means (a.k.a. marginal means, lsmeans, or EM means) from a GEE model fitted in R?

I am trying to obtain model-predicted means and CI's for a categorical predictor in a GEE model fitted with the geeglm function (geepack package). The model is fitted with no problem, but where I am ...
0
votes
0answers
69 views

Naive vs. robust variance in GEE

I'm analyzing a data set including 40 participants. Each participant played a decision-making game 80 times. I am using a GEE analysis clustered by participant, with an exchangeable working matrix. ...
1
vote
0answers
205 views

fitting an exponential decay onto a regression line

I have data for adherence to medicines which follows a downward linear trend for about 6 months (from 100%) and then plateaus at about 50%. Another way of describing it is by saying that adherence ...
2
votes
1answer
241 views

Statistical Power of ROC/AUC Test with non-IID Samples :: To how many IID Samples are my non-IID Samples Equivalent?

I've been assigned to solve the following problem as part of a serious, biological research project. I think I have a tentative solution, but I'm wondering whether the approach I've picked is the ...
2
votes
1answer
256 views

What are the Mild Regularity Conditions in the context of GEEs?

I was reading the Wikipedia Article on Generalized Estimating Equations, where I came across the following sentence: Parameter estimates from the GEE are consistent even when the covariance ...
1
vote
0answers
124 views

Is this longitudinal data too complicated for GLMM or GEE?

After writing this post, I've realized that I am running around in circles, chasing my tail. Any help approaching this problem would be greatly appreciated, as I think I just need to bounce ideas ...
0
votes
1answer
35 views

Repeated measures design with measurements from different groups of animals

In a repeated measured design we measure a particular variable at different time points from the same subjects. In animal experiments, if animals are sacrificed at every time point to measure a ...
4
votes
1answer
227 views

Missing at Random Data in GEE

For a continuous outcome being analyzed using GEE with a linear link, you have assurance that standard errors and point estimates are consistent with a first order trend regardless of distribution of ...
0
votes
0answers
121 views

Interpret scale parameter from GEEGLM output in R

In GEE, the variance of each outcome is equal to the variance function multiplied by the scale parameter. For a continuous outcome the variance function =1. I understand that the scale parameter for ...
1
vote
1answer
148 views

Random or fixed effects in a GLM, or perhaps GEE?

I am involved in the analysis of the effect of an intervention at five different hospitals. The intervention aimed to increase the use of a particular equipement when treeating a patient, so the ...
1
vote
1answer
109 views

Weird looking binned residual plot

My binned residual plot is quite strange looking, the 95% confidence lines are so very jagged, with points between. I have colored this "inside" of the 95% confidence interval because it is really ...