Information Technology Reference
In-Depth Information
3
2
1
0
A
B
C
D
E
F
G
H
I
J
−1
−2
−3
F
IGURE
2.
Average score in each category.There were 75responses overall.
The proportion of responses in each category,forthe possible scores of
−
3
,
−
1
,
0
,
1
,
2
, and
3
,isshown as avertical histogram.Thesolidbaristhe
mean in each case.
2
,
−
0.025
Combination of methods
Overcoding method
Best guess method
Hamming method
0.020
0.015
0.010
0.005
0.000
0
5
10
Depth examined
F
IGURE
9.
Range of scores with eachmethod, ateach depth.Theprincipal
mark in each rangeisthe average score. As can be seen,eachmethod returns
results withinareasonablynarrow band, buttheyare surprisingly different
from each other. Combination is highly effectivein this case.
Fig. 11.6
Further bargraphs. The
upper
graph shows an approach to comparing distributions across
a set of related statistics. The
lower
graph has error bars to show range and scale; however, while
it is a reasonable initial presentation of this data, it could easily be improved
a landscape of
F
values. Such graphs can be powerful explanatory tools, but should
not be used merely because they are dramatic or eye-catching. Another approach
is to experimentally plot
D
against
F
for several fixed values of
E
, and use these
results to choose an
E
value that yields a representative graph; and similarly vary
E
for several fixed
D
, to choose a representative
D
.
