Confidence interval (CI) and error bar

Descriptive stats

Standard deviation: one SD -> 68% of data in CI

Box plot and whisker: Interquartile Range (IQR)

IQR

Inferential stats

Standard error of sampling mean (SEM): one SD -> 68% CI

Z distribution: ~1.96 -> 95% CI (normal(z) distribution)

T distribution: depends on degree of freedom n-1 and %CI (need to correct for bias using n-1)

qnorm(.025,0,sd = 1) # 1 - 0.95 = 0.05; 0.05/2 = 0.025
# -1.959964
qt(0.025,10000)
# -1.960201

Bootstrap 95% CI

standard deviation and percentage

t distribution table