非参数预测模型用于稀疏和不规则的纵向数据
Shixuan Wang1, Seonjin Kim1, Hyunkeun Ryan Cho2
1Department of Statistics, Miami University, Oxford, OH 45056, United States.
Biometrics
|February 19, 2024
概括
这项研究引入了一种新的基于内核的方法,用于从稀疏测量中预测纵向数据趋势. 该方法有效地处理多个预测因素,减少维度,并确定改善轨迹预测的重要因素.
科学领域:
- 统计 统计 统计 统计
- 生物统计学 生物统计学
- 纵向数据分析 纵向数据分析
背景情况:
- 纵向数据分析对于理解随时间的变化至关重要.
- 稀少和不规则的测量数据在准确建模响应轨迹方面存在重大挑战.
- 现有的方法可能会在高维预测空间和识别关键影响因素方面扎.
研究的目的:
- 开发一种基于内核的新型估计器,用于在稀疏的纵向数据中预测平均响应轨迹.
- 在具有多个预测器的模型中解决维度的诅咒.
- 为了确定具有预测意义的功能共变量.
主要方法:
- 提出了一个内核估计器,根据L2度量空间相似性权重主体轨迹.
- 引入了具有多变量高斯核的乘法模型,用于维度缩小和共变量选择.
- 在温和的规律性条件下分析非参数估计器的非对称性属性.
主要成果:
- 拟议的方法在预测平均响应轨迹方面表现出强度和灵活性.
- 乘法模型有效地减少了维度,并选择了重要的功能共变量.
- 模拟研究通过稀疏和不规则的数据证实了该方法的性能.
结论:
- 基于内核的估计器为分析稀疏的纵向数据提供了一个强大的工具.
- 该方法为复杂数据集中的维度缩小和共变量选择提供了灵活的方法.
- 该方法通过模拟和对现实世界的数据的应用来验证,例如弗雷明汉心脏研究.
相关概念视频
Residuals and Least-Squares Property
7.4K
The vertical distance between the actual value of y and the estimated value of y. In other words, it measures the vertical distance between the actual data point and the predicted point on the line
If the observed data point lies above the line, the residual is positive, and the line underestimates the actual data value for y. If the observed data point lies below the line, the residual is negative, and the line overestimates the actual data value for y.
The process of fitting the best-fit...
If the observed data point lies above the line, the residual is positive, and the line underestimates the actual data value for y. If the observed data point lies below the line, the residual is negative, and the line overestimates the actual data value for y.
The process of fitting the best-fit...
7.4K
Model Approaches for Pharmacokinetic Data: Distributed Parameter Models
69
Pharmacokinetic models are mathematical constructs that represent and predict the time course of drug concentrations in the body, providing meaningful pharmacokinetic parameters. These models are categorized into compartment, physiological, and distributed parameter models.
The distributed parameter models are specifically designed to account for variations and differences in some drug classes. This model is particularly useful for assessing regional concentrations of anticancer or...
The distributed parameter models are specifically designed to account for variations and differences in some drug classes. This model is particularly useful for assessing regional concentrations of anticancer or...
69
Parametric Survival Analysis: Weibull and Exponential Methods
430
Parametric survival analysis models survival data by assuming a specific probability distribution for the time until an event occurs. The Weibull and exponential distributions are two of the most commonly used methods in this context, due to their versatility and relatively straightforward application.
Weibull Distribution
The Weibull distribution is a flexible model used in parametric survival analysis. It can handle both increasing and decreasing hazard rates, depending on its shape parameter...
Weibull Distribution
The Weibull distribution is a flexible model used in parametric survival analysis. It can handle both increasing and decreasing hazard rates, depending on its shape parameter...
430
Survival Tree
85
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a...
Building a Survival Tree
Constructing a...
85
Prediction Intervals
2.3K
The interval estimate of any variable is known as the prediction interval. It helps decide if a point estimate is dependable.
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
2.3K
Mechanistic Models: Compartment Models in Individual and Population Analysis
41
Mechanistic models are utilized in individual analysis using single-source data, but imperfections arise due to data collection errors, preventing perfect prediction of observed data. The mathematical equation involves known values (Xi), observed concentrations (Ci), measurement errors (εi), model parameters (ϕj), and the related function (ƒi) for i number of values. Different least-squares metrics quantify differences between predicted and observed values. The ordinary least...
41


