符号
Sigma
Mu
Mean 平均数
样本平均和 population 平均
illustration:
Median 中位数位置
从小到大排序, location: 0.5(n+1)
Mode
most frequently category
in chart call modal?
Skewness 偏态
skewed to the left/right
symmetric - 对称
unimodal - 只有一个高点
bimodal - 有两个高点
illustration:
Mean vs. Median
symmetric are same
skewed are diff - mean 相比 median 向低处偏移
Trimmed Means 修剪
Categorical Data
True proportion = p (真实比例)
sample proportion =