标记基于使用加权和自我校准预测器的线性混合模型的不寻常集群
Charles E McCulloch1, John M Neuhaus1, Ross D Boylan1
1Division of Biostatistics, Department of Epidemiology and Biostatistics, University of California, San Francisco 94158, United States.
Biometrics
|April 2, 2024
概括
新的统计方法准确地识别层次数据中的极端集群,改进了现有的方法. 这些自我校准的方法提供更高的正确标记率,同时控制错误,这对于医疗保健质量评估至关重要.
科学领域:
- 生物统计学 生物统计学
- 医疗保健服务研究 医疗服务研究
- 统计建模 统计建模
背景情况:
- 层次统计模型通常使用集群特定的拦截来分析集群数据 (例如,医院内的患者).
- 预测拦截通常用于识别极端或边缘集群,例如表现不佳的医院或严重健康变化的患者.
- 基于最好的线性无偏预测器 (BLUP) 和固定效应预测器的现有标志极端集群的方法表现不佳.
研究的目的:
- 在等级模型中评估极端集群的各种标记规则的性能.
- 开发和评估用于准确标记极端集群的新方法,并控制错误率.
- 为了比较新的标记方法与以前提出的方法的有效性.
主要方法:
- 使用理论计算和全面的数值评估来评估标记规则的性能.
- 该研究考虑了不同的预测因素和准确度指标,以确定极端集群.
- 开发了新的"自我校准"标记方法来控制不正确的标记率.
主要成果:
- 以前提出的基于BLUP和固定效应预测器的标记规则显示出不可接受的高错误标记率或过于保守.
- 新开发的方法有效控制不正确的标记率.
- 与现有方法相比,新方法显示的正确标记率要高得多.
结论:
- 在等级模型中标记极端集群的现有方法是不够的.
- 提出的自我校准方法为识别极端集群提供了统计学上合理和实用的方法.
- 这些改进的方法有实际应用,例如分析喘患者住院时间的儿科医院长度.
更多相关视频
相关概念视频
Cluster Sampling Method
11.9K
Appropriate sampling methods ensure that samples are drawn without bias and accurately represent the population. Because measuring the entire population in a study is not practical, researchers use samples to represent the population of interest.
To choose a cluster sample, divide the population into clusters (groups) and then randomly select some of the clusters. All the members from these clusters are in the cluster sample. For example, if you randomly sample four departments from your...
To choose a cluster sample, divide the population into clusters (groups) and then randomly select some of the clusters. All the members from these clusters are in the cluster sample. For example, if you randomly sample four departments from your...
11.9K
Calibration Curves: Linear Least Squares
1.3K
A calibration curve is a plot of the instrument's response against a series of known concentrations of a substance. This curve is used to set the instrument response levels, using the substance and its concentrations as standards. Alternatively, or additionally, an equation is fitted to the calibration curve plot and subsequently used to calculate the unknown concentrations of other samples reliably.
For data that follow a straight line, the standard method for fitting is the linear...
For data that follow a straight line, the standard method for fitting is the linear...
1.3K
Mechanistic Models: Compartment Models in Algorithms for Numerical Problem Solving
53
Mechanistic models play a crucial role in algorithms for numerical problem-solving, particularly in nonlinear mixed effects modeling (NMEM). These models aim to minimize specific objective functions by evaluating various parameter estimates, leading to the development of systematic algorithms. In some cases, linearization techniques approximate the model using linear equations.
In individual population analyses, different algorithms are employed, such as Cauchy's method, which uses a...
In individual population analyses, different algorithms are employed, such as Cauchy's method, which uses a...
53
Mechanistic Models: Compartment Models in Individual and Population Analysis
39
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...
39
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
Expected Frequencies in Goodness-of-Fit Tests
2.5K
A goodness-of-fit test is conducted to determine whether the observed frequency values are statistically similar to the frequencies expected for the dataset. Suppose the expected frequencies for a dataset are equal such as when predicting the frequency of any number appearing when casting a die. In that case, the expected frequency is the ratio of the total number of observations (n) to the number of categories (k).
2.5K


