A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis
Generalized additive models provide a flexible and easily-interpretable method for uncovering a nonlinear relationship between response and covariates. In many situations, the effect of a continuous covariate on the response varies across groups defined by the levels of a categorical variable. When...
Main Authors: | , , |
---|---|
Format: | Article |
Language: | English |
Published: |
AIMS Press
2022-04-01
|
Series: | Mathematical Biosciences and Engineering |
Subjects: | |
Online Access: | https://www.aimspress.com/article/doi/10.3934/mbe.2022302?viewType=HTML |
_version_ | 1818204231913439232 |
---|---|
author | Javier Roca-Pardiñas Celestino Ordóñez Luís Meira Machado |
author_facet | Javier Roca-Pardiñas Celestino Ordóñez Luís Meira Machado |
author_sort | Javier Roca-Pardiñas |
collection | DOAJ |
description | Generalized additive models provide a flexible and easily-interpretable method for uncovering a nonlinear relationship between response and covariates. In many situations, the effect of a continuous covariate on the response varies across groups defined by the levels of a categorical variable. When confronted with a considerable number of groups defined by the levels of the categorical variable and a factor‐by‐curve interaction is detected in the model, it then becomes important to compare these regression curves. When the null hypothesis of equality of curves is rejected, leading to the clear conclusion that at least one curve is different, we may assume that individuals can be grouped into a number of classes whose members all share the same regression function. We propose a method that allows determining such groups with an automatic selection of their number by means of bootstrapping. The validity and behavior of the proposed method were evaluated through simulation studies. The applicability of the proposed method is illustrated using real data from an experimental study in neurology. |
first_indexed | 2024-12-12T03:37:57Z |
format | Article |
id | doaj.art-77aab71562154004ab4a375c81235512 |
institution | Directory Open Access Journal |
issn | 1551-0018 |
language | English |
last_indexed | 2024-12-12T03:37:57Z |
publishDate | 2022-04-01 |
publisher | AIMS Press |
record_format | Article |
series | Mathematical Biosciences and Engineering |
spelling | doaj.art-77aab71562154004ab4a375c812355122022-12-22T00:39:45ZengAIMS PressMathematical Biosciences and Engineering1551-00182022-04-011976435645410.3934/mbe.2022302A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysisJavier Roca-Pardiñas0Celestino Ordóñez1Luís Meira Machado21. Department of Statistics and Operational Research, Vigo University, Vigo 36310, Spain2. Department of Mining Exploitation and Prospecting, Geomatics and Computer Graphics Lab, Oviedo University, Mieres 33600, Spain3. Center of Mathematics, Minho University, Braga 4704-553, PortugalGeneralized additive models provide a flexible and easily-interpretable method for uncovering a nonlinear relationship between response and covariates. In many situations, the effect of a continuous covariate on the response varies across groups defined by the levels of a categorical variable. When confronted with a considerable number of groups defined by the levels of the categorical variable and a factor‐by‐curve interaction is detected in the model, it then becomes important to compare these regression curves. When the null hypothesis of equality of curves is rejected, leading to the clear conclusion that at least one curve is different, we may assume that individuals can be grouped into a number of classes whose members all share the same regression function. We propose a method that allows determining such groups with an automatic selection of their number by means of bootstrapping. The validity and behavior of the proposed method were evaluated through simulation studies. The applicability of the proposed method is illustrated using real data from an experimental study in neurology.https://www.aimspress.com/article/doi/10.3934/mbe.2022302?viewType=HTMLclustering of regression curvesfactor-by-curve interactiongeneralized additive modelmultiple regression curvesnonlinear regressionnumber of groups |
spellingShingle | Javier Roca-Pardiñas Celestino Ordóñez Luís Meira Machado A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis Mathematical Biosciences and Engineering clustering of regression curves factor-by-curve interaction generalized additive model multiple regression curves nonlinear regression number of groups |
title | A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis |
title_full | A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis |
title_fullStr | A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis |
title_full_unstemmed | A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis |
title_short | A method for determining groups in nonparametric regression curves: Application to prefrontal cortex neural activity analysis |
title_sort | method for determining groups in nonparametric regression curves application to prefrontal cortex neural activity analysis |
topic | clustering of regression curves factor-by-curve interaction generalized additive model multiple regression curves nonlinear regression number of groups |
url | https://www.aimspress.com/article/doi/10.3934/mbe.2022302?viewType=HTML |
work_keys_str_mv | AT javierrocapardinas amethodfordetermininggroupsinnonparametricregressioncurvesapplicationtoprefrontalcortexneuralactivityanalysis AT celestinoordonez amethodfordetermininggroupsinnonparametricregressioncurvesapplicationtoprefrontalcortexneuralactivityanalysis AT luismeiramachado amethodfordetermininggroupsinnonparametricregressioncurvesapplicationtoprefrontalcortexneuralactivityanalysis AT javierrocapardinas methodfordetermininggroupsinnonparametricregressioncurvesapplicationtoprefrontalcortexneuralactivityanalysis AT celestinoordonez methodfordetermininggroupsinnonparametricregressioncurvesapplicationtoprefrontalcortexneuralactivityanalysis AT luismeiramachado methodfordetermininggroupsinnonparametricregressioncurvesapplicationtoprefrontalcortexneuralactivityanalysis |