#  file21.txt
#
#  Reference:
#
#    John Hartigan,
#    Clustering Algorithms,
#    Wiley, 1975.
#    ISBN 0-471-35645-X
#    LC: QA278.H36
#    Dewey: 519.5'3
#
#  Six pieces of hardware were considered.
#  Every possible set of three distinct pieces of hardware was examined,
#  and a judgment was made about which two pieces were most similar.
#  The results were reported by listing the closest pair with parentheses
#  surrounding them, followed by the "odd" item.
#
#  "N" is nail, "P" Phillips head screw, "B" bolt, "T" tack, "F" finishing
#  nail, and "S" is screw.
#
"Triads based on Hardware, Hartigan page 178"
1 columns
20 rows
(PB)N
(NT)P
(NF)P
(PS)N
(NT)B
(NF)B
(BS)N
(NF)T
(NT)S
(NF)S
(PB)T
(PB)F
(PS)B
(TF)P
(PS)T
(PS)F
(TF)B
(BS)T
(BS)F
(TF)S