Stem-and-leaf displays for the Arsenic data

1.    Default Systat output

SYSTAT VERSION 6.0.1
COPYRIGHT (C) 1996, SPSS INC

>IMPORT 'W:\ENVSTATS\CHAP_03\ARSENI~1.DBF' / TYPE=DBASE
IMPORT successfully completed.

Stem and Leaf Plot of variable: VALUE, N = 40
Minimum: 1.500
Lower hinge: 5.100
Median: 6.750
Upper hinge: 10.600
Maximum: 27.200

0   1
0   22223
0 H 44455555555
0 M 66667777
0   8999
1 H 011
1   223
1   5
1   67
* * * Outside Values * * *
2   47

Questions

1. What useful information was left out of this stem-and-leaf plot?  (There are several good answers.)

2.    Systat output modified using the 10*log(N) rule (10*log(40) = 16)

>STEM VALUE/ LINE=16

Stem and Leaf Plot of variable: VALUE, N = 40
Minimum: 1.500
Lower hinge: 5.100
Median: 6.750
Upper hinge: 10.600
Maximum: 27.200

 1   5
 2   1578
 3   6
 4   669
 5 H 02455688
 6 M 4778
 7   1338
 8   1
 9   123
10 H 2
11   06
12   14
13   9
14
15   3
16   0
17   0
* * * Outside Values * * *
24   7
27   2

3.    Output from sl.exe ((c) 1989 IDT)

SL.EXE is a DOS program: run it from a command line in Windows.  It is launched by typing its name.  It will prompt for the name of a data file.  The file should contain the data, one number per line, with no blank lines.  SL does not identify outlying data.  However, it does decorate its plot with depths as shown in the sample output below.

W:/envstats/chap_03>sl
Data file> arsenic.txt
Exponent:  0
  Width :  1
  Start :  1
# Lines : 27
# Places:  1

Stem-and-Leaf Diagram for File arsenic.txt
N = 40

Depth Units = 10** 0
  1  1*|5
  5  2*|1 5 7 8
  6  3*|6
  9  4*|6 6 9
 17  5*|0 2 4 5 5 6 8 8
[ 4] 6*|4 7 7 8
 19  7*|1 3 3 8
 15  8*|1
 14  9*|1 2 3
 11 10*|2
 10 11*|0 6
  8 12*|1 4
  6 13*|9
    14*|
  5 15*|3
  4 16*|0
  3 17*|0
    18*|
    19*|
    20*|
    21*|
    22*|
    23*|
  2 24*|7
    25*|
    26*|
  1 27*|2

Questions

1. Which, if any, of these plots are "better"?  In what ways?

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