Questions tagged [r]
Use this tag for any *on-topic* question that (a) involves `R` either as a critical part of the question or expected answer, & (b) is not *just* about how to use `R`.
30,436 questions
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Why is the ones trick making my hurdle model crash in jags?
I'm running a hurdle model in JAGS but if randomly crashes for reasons I cannot determine. The model describes the presence absence of a species and, when the species is present, its biomass. It uses ...
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How to estimate the impact of a continuous variable x on a continuous dependent variable y by group of increasing range of y?
From a database of about 40,000 rows, I would like to test whether the concentration of a drug x0 has an impact on the concentration of a plasma biomarker ...
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R Cox.zph vs Stata estat phtest
Looking at the GBSG2 dataset from TH.data package I did a Cox model in Stata and R on the same covariables and tested for proportional hazards using cox.zph in R and estat phtest in Stata. As far as I ...
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Fine & Gray fails due to singularity - but Cox and binomial regression do not
I'm currently performing an analysis with various survival models. I have relatively many binary covariates (up to 8) with a relatively low number of events (~80).
Using the Fine & Gray competing ...
Murster
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Why the one-sided p-value is so much smaller than two-sided for K-S test? [closed]
I am using r function ks.test(x,y) to perform a K-S test on 2 sets of data (significance of difference between distributions).
When calculating the two-sided p-...
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Logistic model giving mixed results
I am currently creating two logistic regression models (one with forward selection and one with LASSO) using R to predict whether a patient has a malignant or benign breast cancer from this dataset: ...
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Problem with fractional cointegration test result interpretation
I'm struggling to interpret result of cointegration test (fractional case (Johansen and Nielsen, 2012)).
This test suggest that in two non-stationary series could be a cointegration but in fractional ...
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Helmert contrasts in lm() or emmeans()
For context, I used to set contrasts in my model by assigning them to my variable as a matrix using contrasts().
For example, for a factor with four levels and a ...
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Writing lme mixed model as equation: equatiomatic vs LearnVizLMM - which one is right?
Suppose we have:
library(lme4)
data("sleepstudy")
model = lmer(Reaction ~ Days + (Days|Subject), data = sleepstudy)
Now we extract the equation with ...
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Plotting Boxplots with measured variable on the X-axis [closed]
I have data set on underground water mineral content measured along a river basin at three locations: Upper, Middle and Lower. The measured values are Hydrocarbonate, Chloride, Sulphate content and EC....
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Specifying a correct correlation structure in a hierarchical linear model using nlme's "correlation"-argument
I am modelling longitudinal data, using hierarchical linear modeling (HLM). There are 6 measurement points. We assume that the data between these measurement points is correlated. To account for such ...
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Sample size calculation Split Plot design
I'm currently trying to calculate the sample size for a completely randomized split-plot design. The design includes two treatments at the whole-plot level and two treatments at the sub-plot level. ...
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Handling recurring convergence issues in multiple change point detection in R
I'm trying to run a series of multiple change point models on a large number of time series variables, but I am running into occasional convergence issues that I would like advice on how to handle. I ...
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Calibration with all data: data-poor scenarios
I’m working on species distribution modeling with binary data (presence��/ absence, 1 / 0). My target species is extremely rare (prevalence ~0.014), so my dataset is almost all zeros and just a handful ...
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How to estimate Realtive Risk in GLM models with interaction term?
I want to assess if high levels of an A variable affect the impact of temperature on hospital admissions. I used a dlnm models combined with glm to estimate RR:
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