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Scalar-on-function regression for predicting distal outcomes from intensively gathered longitudinal data:
John J Dziak1, Donna L Coffman2, Matthew Reimherr3
1The Methodology Center, The Pennsylvania State University, University Park, PA.
Statistics Surveys
|November 21, 2019
Summary
Predicting health outcomes like smoking cessation from longitudinal data requires careful interpretation of scalar-on-function regression models. This study offers practical guidelines for understanding the joint relationship between time-varying data and outcomes.
Area of Science:
- Statistics
- Biostatistics
- Longitudinal Data Analysis
Background:
- Predicting distal outcomes from longitudinal data is crucial in health research.
- Scalar-on-function regression is a method for analyzing such relationships.
- Interpreting the fitted coefficient function in these models presents unique challenges.
Purpose of the Study:
- To provide practical guidelines for interpreting scalar-on-function regression coefficients.
- To clarify the distinction between joint and marginal relationships in longitudinal analysis.
- To illustrate interpretation methods using a smoking cessation study.
Main Methods:
- Semiparametric scalar-on-function regression was employed.
- The study focused on the interpretation of the fitted coefficient regression function.
- Data from a smoking cessation study was used for illustration.
Main Results:
- The fitted coefficient function represents a joint relationship between time points and the outcome.
- Misinterpretation can arise if treated as a marginal or cross-sectional relationship.
- Guidelines were developed to aid practitioners in correct interpretation.
Conclusions:
- Accurate interpretation of scalar-on-function regression is essential for valid scientific conclusions.
- The provided guidelines facilitate understanding the complex temporal relationships in longitudinal data.
- This work enhances the application of functional data analysis in health-related research.
Keywords:
Distal outcomesfunctional regressionintensive longitudinal datascalar-on-function regressiontrajectoriesMore Related Videos
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