关于在棒球投球和替代分析方法中进行子组分析的连续数据的离散
Kevin A Giordano1, Kyle W Wasserberger2
1Departments of Orthopedics and Physical Therapy, Holy Cross Orthopedics Institute, Fort Lauderdale, FL, USA.
Sports biomechanics
|July 10, 2024
概括
分析棒球投手的数据显示,将投球速度分成几组会扭曲结果. 将速度视为连续变量,可以更准确地了解投者对肘扭矩的理解.
科学领域:
- 体育 生物力学 运动 生物力学
- 棒球分析 棒球分析
- 伤害预防 预防伤害
背景情况:
- 投球速度通常通过创建高和低速度子组来分析.
- 这种方法在检查生物机械因素时可能会导致分析差异,例如肘部扭矩.
- 斜率速度自然存在于连续的光谱中,而不是离散的类别.
研究的目的:
- 为了比较分组音速与将其视为连续变量之间的分析差异.
- 通过使用不同的分析方法,检查球速对肘部形扭矩的影响.
- 为体育生物力学研究人员提供有关连续变量数据分析的建议.
主要方法:
- 追溯分析了来自1315个积极竞争的投手的运动捕捉数据.
- 三种分析方法的比较:线性回归,中位数分割t试验和四分位数分割t试验.
- 检查球速与肘部扭矩之间的关系.
主要成果:
- 线性回归显示,球的速度显著影响了肘部扭矩 (R2=0.280).
- 中位分裂速度小组降低了可预测性 (R2=0.180),而极端分裂小组的人工膨胀效应大小 (R2=0.347).
- 区分一个连续变量,比如速,会扭曲与依赖变量的关系,比如肘部扭矩.
结论:
- 研究人员应该避免将连续变量 (如投球速度) 分为分析子组.
- 将转速视为连续变量,可以更准确地表示其与生物力学结果的关系.
- 回归分析允许精确估计独立变量的整个范围内的依赖变量.
相关概念视频
01:02Quantifying and Rejecting Outliers: The Grubbs Test
1.5K
Sometimes, a data set can have a recorded numerical observation that greatly deviates from the rest of the data. Assuming that the data is normally distributed, a statistical method called the Grubbs test can be used to determine whether the observation is truly an outlier. To perform a two-tailed Grubbs test, first, calculate the absolute difference between the outlier and the mean. Then, calculate the ratio between this difference and the standard deviation of the sample. This...
1.5K
01:21Friedman Two-way Analysis of Variance by Ranks
180
Friedman's Two-Way Analysis of Variance by Ranks is a nonparametric test designed to identify differences across multiple test attempts when traditional assumptions of normality and equal variances do not apply. Unlike conventional ANOVA, which requires normally distributed data with equal variances, Friedman's test is ideal for ordinal or non-normally distributed data, making it particularly useful for analyzing dependent samples, such as matched subjects over time or repeated measures...
180
01:16Stratified Sampling Method
11.9K
Sampling is a technique to select a portion (or subset) of the larger population and study that portion (the sample) to gain information about the population. The sampling method ensures 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 stratified sample, divide the population into groups called strata and then take a...
To choose a stratified sample, divide the population into groups called strata and then take a...
11.9K
01:16Statistical Inference Techniques in Hypothesis Testing: Parametric Versus Nonparametric Data
120
Statistical inference techniques, paramount in hypothesis testing, differentiate into two broad categories: parametric and nonparametric statistics.
Parametric statistics, as the name suggests, assumes that data follow a specific distribution, often a normal distribution. This assumption enables robust hypothesis testing and estimation. Parametric methods, like the Student's t-test or Goodness-of-fit test, are frequently employed in biostatistics due to their robustness. For instance,...
Parametric statistics, as the name suggests, assumes that data follow a specific distribution, often a normal distribution. This assumption enables robust hypothesis testing and estimation. Parametric methods, like the Student's t-test or Goodness-of-fit test, are frequently employed in biostatistics due to their robustness. For instance,...
120
00:57Modified Boxplots
9.5K
A standard box and whisker plot informs us about the spread of the data in a given sample. One can identify the minimum value, maximum value, first quartile value, second quartile or median value, and third quartile.
However, the box plot does not tell the reader about outliers - values that lie far from the center of the data. We can modify the standard box and whisker plot to identify the outliers and visualize the actual spread of the data in a sample.
Initially, we calculate the adjusted...
However, the box plot does not tell the reader about outliers - values that lie far from the center of the data. We can modify the standard box and whisker plot to identify the outliers and visualize the actual spread of the data in a sample.
Initially, we calculate the adjusted...
9.5K
01:14Decision Making: Traditional Method
4.0K
The process of hypothesis testing based on the traditional method includes calculating the critical value, testing the value of the test statistic using the sample data, and interpreting these values.
First, a specific claim about the population parameter is decided based on the research question and is stated in a simple form. Further, an opposing statement to this claim is also stated. These statements can act as null and alternative hypotheses, out of which a null hypothesis would be a...
First, a specific claim about the population parameter is decided based on the research question and is stated in a simple form. Further, an opposing statement to this claim is also stated. These statements can act as null and alternative hypotheses, out of which a null hypothesis would be a...
4.0K