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Both rankings are listed in Table
3.1
. The attributes are given in decreasing order
with respect to their importance as perceived by the two algorithms, that is staring
with these variables which are considered more important, then with gradually lower
and lower significance expressed by scores they were assigned. For comparison
purposes also both reversed orderings of variables were tested in the second stage of
experiments, presented in the next section.
When the two rankings of features are compared against each other we can observe
some similarities, after all both algorithms operate on the same input set. However,
there are also significant differences. They both consider “and” attribute as the most
important and “as” takes the same place, but the rest of variables is put in a different
order. “But” and “that”, placed among lowest ranking for DRSA order, are among
the highest ranking features for Relief. “Of”, the last on Relief list, is in the upper half
for DRSA ranking, and so on. Different focus of both ranking algorithms resulted in
different weights being assigned to majority of attributes.
Table 3.1
Rankings of
features obtained in the first
stage of experiments
Nr
Ranking by
Relief algorithm
Embedded DRSA processing
1
and
and
2
that
not
3
but
by
4
from
.
5
:
on
6
not
from
7
?
in
8
for
;
9
by
if
10
-
of
11
what
,
12
at
!
13
!
:
14
with
at
15
if
-
16
on
to
17
as
as
18
to
this
19
this
with
20
in
?
21
(
what
22
.
(
23
,
that
24
;
for
25
of
but
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