Questions tagged [linearity]
The linearity tag has no usage guidance.
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A few paths in path analysis violated linearity assumption, but other paths met the linearity assumption
I'm running a path analysis of serial mediation. Upon checking the linearity assumption, I found that a few paths do NOT have linear relationships, as indicated by rainbow tests and crPlots. However, ...
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Cubic splines for Cox models
I have a question about cubic splines. I want to be sure that I understood correctly. When I perform a Cox model with proportional hazards, if I insert continous variables in the model I have to check ...
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Cubic splines in Cox model
I have a question about the cubic splines used in the Cox model to test the linearity for the continuous variables. I read that usually the knots chosen are the quantiles. Can you find different ...
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Non-indicator variable
In OLS regression, do the control variables need to have linear relationship to the dependent variable (linearity assumption) or just the independent/explanatory variables? Thank you.
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Calculating Expectation using the Linearity of Expectation law and sum of indicator random variables
I'm attempting to complete the problem sets for the Stanford CS109 Statistics course from 2021 as I follow along with the lectures.
I'm stuck on a particular problem in one of these problem sets. I ...
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Checking the linearity assumption in multiple regression
If I wanted to check the mentioned assumption, it is quite easy for only 1 predictor, but what if I have several?
I read online that I can plot the residuals vs predicted and see there is no pattern, ...
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An example of a random variable $y\in L^\dagger_2$ having more than one linear combination, $y = \Sigma_{i}\alpha_i x_i = \Sigma_{i}\beta_i x_i$
In the answer for the following exercise:
Let $\{x_1,...,x_n\}$ be a finite collection of random variables with $E(x_i^2) \lt \infty$ ($i = 1,..., n$). Show that the set of all linear combinations $\...
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Doubt on checking linearity assumption in a mixed-ANCOVA design
I am a PhD student and I have to run a mixed-ANCOVA on some questionnaire scores (my dependent variable) according to the following model. Factors of ANCOVA are (a) Timepoint (pre-intervention, post-...
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Test Linearity Assumption - Hayes PROCESS
Before running the Hayes PROCESS for my moderated mediation, I would like to ensure first, that the linearity assumption is fulfilled.
However, at this point, I am not sure which variables need to be ...
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How to Check Linearity Assumption in Logistic Regression with a Large Dataset?
I am working with a very large dataset that essentially covers the entire population of interest. I want to assess the linearity assumption between an independent variable and the log(odds) of the ...
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Upward trend in Residuals vs. Fitted - Violation of linearity?
I am currently working with longitudinal data using a linear mixed model (lme4 R package).
The linearity plot (fit with ...
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Provide an intuitive example of the linearity of expectation
Can anyone explain the linearity of expectation in an intuitive way? I have been trying to understand this for far too long now. Please don't use any equations and such, try to use real world examples ...
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How to interpret scatterplot to test linearity b/w covariate and DV?
I'm doing an ANCOVA on a fictitious dataset of math test results (DV) by group (n1 = 50 online training; n2 = 50 no training) with previous math ability as a (covariate) to see if there is a ...
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Continuous predictor variable has non-linear association with log odds of response
I'd like to know if a continuous predictor variable (sal) predicts a binary response (empty) in a logistic mixed effect model, but discovered there is a non-linear relationship between the predictor ...
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Testing the linearity assumptions for categorical predictors
Me and my friend are currently writing our final essay but we are having some problems with our analysis…
We are doing an hierarchical multiple regression, and we has some categorical predictors (like ...
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