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Lazarus K Mramba1, Xiang Liu2, Kristian F Lynch2

  • 1Health Informatics Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA. Lazarus.Mramba@epi.usf.edu.

概括

使用四分位数范围 (IQR) 算法识别访问级异常值对于纵向研究中的数据质量控制至关重要. 极端的维生素B12值显著影响了考克斯回归模型,改变了与小岛自身免疫 (IA) 风险的关联.

相关概念视频

Outliers and Influential Points01:08

Outliers and Influential Points

An outlier is an observation of data that does not fit the rest of the data. It is sometimes called an extreme value. When you graph an outlier, it will appear not to fit the pattern of the graph. Some outliers are due to mistakes (for example, writing down 50 instead of 500), while others may indicate that something unusual is happening. Outliers are present far from the least squares line in the vertical direction. They have large "errors," where the "error" or residual is the...
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Survival Tree01:19

Survival Tree

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 Building a Survival Tree
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Longitudinal Research02:20

Longitudinal Research

Sometimes we want to see how people change over time, as in studies of human development and lifespan. When we test the same group of individuals repeatedly over an extended period of time, we are conducting longitudinal research. Longitudinal research is a research design in which data-gathering is administered repeatedly over an extended period of time. For example, we may survey a group of individuals about their dietary habits at age 20, retest them a decade later at age 30, and then again...
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What Are Outliers?01:12

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Comparing the Survival Analysis of Two or More Groups01:20

Comparing the Survival Analysis of Two or More Groups

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Quantifying and Rejecting Outliers: The Grubbs Test01:02

Quantifying and Rejecting Outliers: The Grubbs Test

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