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arXiv · 2305.03634

On the use of ordered factors as explanatory variables

Adelchi Azzalini
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Abstract

Consider a regression or some regression-type model for a certain response variable where the linear predictor includes an ordered factor among the explanatory variables. The inclusion of a factor of this type can take place is a few different ways, discussed in the pertaining literature. The present contribution proposes a different way of tackling this problem, by constructing a numeric variable in an alternative way with respect to the current methodology. The proposed techniques appears to retain the data fitting capability of the existing methodology, but with a simpler interpretation of the model components.

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Adelchi Azzalini. 2023-05-05. On the use of ordered factors as explanatory variables. https://doi.org/10.1002/sta4.624

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