stamp: Data on Thickness of Stamps

In bootstrap: Functions for the Book "An Introduction to the Bootstrap"

Description

Thickness in millimeters of 485 postal stamps, printed in 1872. The stamp issue of that year was thought to be a "philatelic mixture", that is, printed on more than one type of paper. It is of historical interest to determine how many different types of paper were used.

Usage

data(stamp)

Format

A data frame with 485 observations on the following variable.

Thickness

Thickness in millimeters, a numeric vector

Details

In the book, this is used to exemplify determination of number of modes. It is also used for kernel density estimation.

Note

The main example in the book is on page 227. See also the CRAN package diptest for an alternative method.

Source

Efron, B. and Tibshirani, R. (1993) An Introduction to the Bootstrap. Chapman and Hall, New York, London.

Examples

summary(stamp)
with(stamp, {hist(Thickness);
             plot(density(Thickness), add=TRUE)})

Example output

   Thickness      
 Min.   :0.06000  
 1st Qu.:0.07500  
 Median :0.08000  
 Mean   :0.08602  
 3rd Qu.:0.09800  
 Max.   :0.13100  
Warning messages:
1: In plot.window(...) : "add" is not a graphical parameter
2: In plot.xy(xy, type, ...) : "add" is not a graphical parameter
3: In axis(side = side, at = at, labels = labels, ...) :
  "add" is not a graphical parameter
4: In axis(side = side, at = at, labels = labels, ...) :
  "add" is not a graphical parameter
5: In box(...) : "add" is not a graphical parameter
6: In title(...) : "add" is not a graphical parameter

bootstrap documentation built on June 17, 2019, 5:04 p.m.