Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [polr]

polr refers to a R function in package MASS for ordered logistic or probit regression.

polr is a R function in package MASS for ordered logistic or probit regression. It fits a logistic or probit regression model to an ordered factor response. The default logistic case is proportional odds logistic regression, after which the function is named.

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How to use ordinal logistic regression with random effects?

In my study I will be measuring workload with several metrics. With heart-rate variability (HRV), electrodermal activity (EDA) and with a subjective scale (IWS). After normalization the IWS has three values: Workload lower than normal Workload is…
Robin Kramer
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Checking the proportional odds assumption holds in an ordinal logistic regression using polr function

I have used the ‘polr’ function in the MASS package to run an ordinal logistic regression for an ordinal categorical response variable with 15 continuous explanatory variables. I have used the code (shown below) to check that my model meets the…
Char_leopard
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Plot predict probabilities wiht ggplot2 and brms

I'm a PhD student in psycholinguistics and I'm having trouble in modeling some ordinal data. I have an ordinal response (completely disagree, disagree, neutral, agree, completely agree) and two categorical predictors (order: um-todo x todo-um;…
Igor de Oliveira Costa
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Interpreting interaction odds ratios in ordinal regression

I have run an ordinal regression in R using polr from the MASS package. I'm trying to interpret an interaction. Both predictors are categorical. Here is an example: Predicting success in the job market (Low, medium or high) from exam performance…
Amy
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Interpreting results of multinomial model using polr

I am trying to correctly interpret and plot the effects of a multinomial model fit in R. The data and script are here for reproducing the problem. The multinomial variable describes different outcomes of a videogame where players have to hit a…
Agus Camacho
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Is there an R package to check the proportional odds assumpion?

is there an R package/function to implement the parallel slope test given a clm (ordinal package) or polr (MASS) package?
Giorgio Spedicato
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Understanding ordered logistic regression

I have the following toy data: x <- structure(c(2L, 2L, 3L, 1L, 2L, 3L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 2L, 2L, 2L, 2L, 3L, 2L, 2L, 2L, 2L, 2L, 2L, 3L, 2L, 2L, 2L, 3L, 2L, 2L, 2L, 1L, 2L, 1L, 2L, 2L, 2L, 3L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L,…
teucer
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A couple of polr Issues for ordinal regression with ordinal independent variables

I am having trouble using polr for a ordinal regression because I also have ordinal independent variables. Looking online it looks like I should either convert them to categorical dummy variables or go the numerical continuous route. Does anyone…
Amy
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Ordinal logistic regression interpretation of polr summary in r

I am trying to interpret the coefficients for the polr model. Where each predictor has three levels, Dissatisfied, Neutral, and Satisfied. Dissatisfied is the baseline. The dependent variable has the same three levels. I need help interpreting the…
Oliver Ruan
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Ordinal logistic regression (polr in R): DV wrong level order

I am (trying) to conduct an ordinal logistic regression for the first time using the polr function in r. I seem to be encountering a problem with the order of my levels of my DV. My DV should have four ordered levels: 'no problems', 'low risk',…
nicola
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What is a good algorithm for measuring the relationship between numerical input variables and ordered categorial output?

I have a dataset with 50 numerical input variables and 1 output column. The output is categorical and ordered. I want to describe the relationship between the numerical variables and the categorial output. There are 3 leves in the categorial output.…
Sorlac
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ordered logistic regression marginal probabilities hit ceiling

I'm running an ordered logistic regression with 3 classes, and I am able to predict the probability of each observation belonging to each class. For some reason one class' probabilities (top40) never rise above a certain threshold. I am using the…
Froblinkin
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Ordered probit model prediction: why highest probabilities and not number of thresholds exceeded?

I'm running ordered probit regression models with polr in R. This question states that for prediction, polr returns the category with the highest probability for given $x$. I would have expected that the predicted category is equal to the number of…
Qaswed
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Ordered Logistic Regression GWAS

I am attempting to do an ordered logistic regression in R on SNP matrixes (presence absence matrix 1 or 0) with three outcomes (1,2,3). I am having an issue of 0 p-values when low numbers (<5%) occur for one the binary categories (one row of the…
SemiQuant
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How should I determine degrees of freedom for t-test in ordinal regression?

I consider a proportional odds (ordinal regression) model, as described in Agresti (2002) and estimated by R base package function MASS. The software reports t-values but no p-values in summary. I wonder how I should determine the degrees of freedom…
tomka
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