The first is a quartile plot from page 125. The data file has entries

x minimum lower-quartile median upper-quartile maximum

A quartile plot combines two vectors plots for the lower and upper quartile and a point plot:

#!/usr/bin/gnuplot
set term svg
set output "tufte.svg"
unset border
set noxtics
set noytics
plot [0:11] [0:10] "./tufte.dat" using 1:2:(0):($3-$2) with vectors nohead ls -1 notitle,\
                   "" using 1:5:(0):($6-$5) with vectors nohead ls -1 notitle,\
                   "" using 1:4 with points pt 7 ps 0.75 lt -1 notitle

The result is