Weighted Absolute Reports
Types of Reports
373
The following figure shows the last few lines of a Relative report:
Weighted Relative Reports
This report is the same as the Relative report, except that it also lists the weighted
geometric mean.
To define a Weighted Relative report:
s
Click
Reports > New > Compare Performance
, and then select the
Value relative to
base report
and the
Weighted by count of base report samples
options.
The weighted geometric mean differs from the geometric mean in that it takes into
account the frequency with which the different command IDs occur. Frequently used
command IDs have a greater influence on the weighted geometric mean than
infrequently used ones--in contrast to the geometric mean, where all command IDs
have equal influence.
The weight applied when calculating the weighted geometric mean for each
command ID equals the number of valid responses for that ID in each report being
compared. If the number of valid responses for a command ID differs among the
reports, the smallest nonzero count is used as its weight.
Mathematically, the weighted geometric mean of a set of values
x
1
,
x
2
, ...,
xk
with
frequencies (weights) of
f
1
,
f
2
, ...,
fk
, where
f
1
+
f
2
+ ... +
fk
=
N
, is expressed as:
x
1
f
1
x
2
f
2
...x
k
f
k
(
)
1
N
/
