statistics-skewed data

参考文献:

http://www.statisticshowto.com/skewed-distribution/



left/negatively-skewed distributions :

  • boxplot:The left whisker will also be longer than the right whisker.

right/positively-skewed distributions

  • the right whisker will be longer.

注意:median未必一定在mean和mode之间

对于too skewed的数据,如果需要进行参数检验(比如ANOVA),就需要用log变换,让它没那么skewed。

何时这么做??

  • Your data is highly skewed to the right (i.e. in the positive direction).
  • The residual’s standard deviation is proportional to your fitted values
  • The data’s relationship is close to exponential.
  • You think the residuals reflect multiplicative errors that have accumulated during each step of the computation.
时间: 2024-11-03 05:29:53

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