New answers tagged interaction
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Strange interaction term estimate in a logistic regression with a large class imbalance between exposure groups. How to interpret?
My knowledge of the field pushes me to think something is wrong, as I would've expected the OR of the interaction term to be either above 1
or not statistically significant.
If the interaction effect ...
- 71.6k
5
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Strange interaction term estimate in a logistic regression with a large class imbalance between exposure groups. How to interpret?
One problem is that you are relying far too much on significance tests and not showing us all the effect sizes. You say that in separate analysis by levels of X, the X=1 test was not significant while ...
- 109k
2
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Appropriate way to configure contrasts and interactions in GLM likelihood ratio test
Sections 6 and 7 of the Bioconductor vignette on creating design matrices for gene expression experiments are helpful here, as is Section 3.3.1 of the edgeR User's Guide. A few issues stand out to me ...
- 86.6k
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Significant pairwise comparisons from emtrends but marginal means are not-significant?
As you know, the emtrends part of the output shows whether the continuous predictor's slopes for each categorical x categorical combination differ from zero and the contrast part shows whether they ...
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Using interaction terms in causal models
I mean is it ok to dig for significant interactions once my effect initially fails to show significance, given no expert / literature knowledge exists about the existence of such interaction effects.
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Synergistic effects: what statistics should I use?
Statistics cannot tell you if an interaction is synergistic!
You need to characterise the dose-response relationship of both agents and see if both together yields an effect that is greater than ...
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5
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Testing the proportional hazards assumption with a time varying covariate
I don't know the origin of the idea that Schoenfeld residuals can't be used for testing proportional hazards (PH) with time-varying covariate values. As Therneau and Grambsch say in Section 4.6:
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Difference in stratification, interaction and subsetting Cox Survival Regression
I would combine model 2 with model 1 and text the interaction. Model 2 tests for the interaction term but assumes the same baseline hazard function for men and women.
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Accepted
How to deal with interaction terms in regression that cannot have a negative product?
Multicollinearity gets a lot of undue attention. As the Wikipedia entry states:
Multicollinearity does not affect the accuracy of the model or its predictions. It is a numerical problem, not a ...
- 86.6k
1
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Accepted
How to interpret standardized simple slopes and indirect effects in R with semTools and lavaan?
I found another post that provided some insight on the topic
Please note that I just edited that 2022 response (because I am not allowed to rescind an accepted answer). Please read there about the ...
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Interaction with dummy variable: How to access std. error, t value, p value, (and others) for the opposite manifestation of dummy
Question 1.
Although you might get the same point estimates within each vs group by deleting the cases in the other vs group, ...
- 86.6k
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Estimated marginal means versus model-derived interaction effects
Interaction terms in linear models assess if group effects differ across measurements. A significant interaction suggests the group's influence on outcomes varies at different times.
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What method should be used if the clusters contains different classes?
This problem violates the so-called cluster hypothesis which states that points in the same cluster should generally belong to the same class. Here the clustering appears uninformative for determining ...
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Accepted
What method should be used if the clusters contains different classes?
The trouble with your example is that these clusters are not particularly informative about the color you aim to predict. If one cluster were mostly blue, another mostly yelllow, etc, then the cluster ...
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