Example applications Bootstrapping (statistics)







smoothed bootstrap

in 1878, simon newcomb took observations on speed of light. data set contains 2 outliers, influence sample mean. (note sample mean need not consistent estimator population mean, because no mean need exist heavy-tailed distribution.) well-defined , robust statistic central tendency sample median, consistent , median-unbiased population median.


the bootstrap distribution newcomb s data appears below. convolution method of regularization reduces discreteness of bootstrap distribution adding small amount of n(0, σ) random noise each bootstrap sample. conventional choice



σ
=
1

/



n




{\displaystyle \sigma =1/{\sqrt {n}}}

sample size n.


histograms of bootstrap distribution , smooth bootstrap distribution appear below. bootstrap distribution of sample-median has small number of values. smoothed bootstrap distribution has richer support.



in example, bootstrapped 95% (percentile) confidence-interval population median (26, 28.5), close interval (25.98, 28.46) smoothed bootstrap.








Comments

Popular posts from this blog

Prosodic bootstrapping Bootstrapping (linguistics)

Principal leitmotifs Music of The Lord of the Rings film series

List of masters Devon and Somerset Staghounds