In this case n = 4.
i
W
:
/
n
ii i
i
WM M
(7)
In this case n = 4.
A is comprehensive judgment matrix. Each
number in the number i line in A multiplied by each
number of the corresponding values in the
i
W
column, and the summation of all products is
()
i
W
.
The calculation of the maximum eigenvalue:
max
/
i
i
AW n W
(8)
In this case, the maximum eigenvalue is equal to
1.3782411.
(4) Consistency Test. Because the matrix structure
made by the experts do not necessarily meets the
matrix consistency. Judge the matrix consistency
test in order to limit this kind of error. Take the
largest eigenvalue and n's relative error as the
consistency indicator of matrix. Denoted by:
max
1
n
CI
n
(9)
( n equals to the order of matrix, also the number of
indexes in matrix.)
If
2n
,the matrix is always exactly the same, it
means
0CI
。
And when
2n
,the ratio of the
matrix's consistency index and the average random
consistency index is random consistency ratio which
is denoted as
CR
.
If
R<0.1C
, the judgment matrix has satisfactory
consistency and the calculated feature vector is
reliable. Otherwise the matrix the experts
constructed has larger error and is out of range. The
matrix needs to be re-adjusted until it gets the
satisfactory consistency.
After calculation, all comparison matrixes are
consistent, and the results are credible.
(5) Calculation of the total weight. The index system
is composed of the first-level indicators and
secondary indicators. Each first-level indicator
contains numbers of secondary-level indexes. As
described above, we calculate four first-level
indicators' weights, and analyze the consistency of
its matrix. And it is the same to the secondary-level
indexes.
Supposing that the indicator
i 's weight is equal
to
i
a ,its j secondary-level indicator's relative
weight is
b .Then this secondary-level indicator's
total weight is
ij
ab
.
In order to verify whether the total weight also
has the satisfaction of consistency, we need to
calculate the total random consistency index, the
indicator is calculated as:
1
1
n
ii
i
n
ii
i
aCI
CR
aRI
(10)
While:
i
a : the number i first-level indicator's weight.
i
CI : the number i first-level indicator's
consistency index value.
i
RI
:
the number i first-level indicator's average
random consistency index values.
The final overall consistency test result is
0.028312 which is far less than 0.1.So it is consistent
with consistency. Evaluation indexes’ weights are in
Table 6, the unadjusted weights.
3.4 Existing Problems in Weights
According to the analysis of the system above, the
following questions are found:
1) There are nine scales 1 to 9 which bring heavy
interference to define the actual level of importance.
According to the statistics, in the valid
questionnaires, 89.93 percent of the scores are
between 1 and 4, and this is not accord with the
actual. And a few high points such as score nine or
eight will cause big effect to the result of the data.
The reason lies in that nine scales range too wide,
and in the economic model evaluation system, the
differences of importance between indexes of the
same layer do not need so big a range. At the same
time, because the differences between the graders
own subjective thoughts, the specific meanings of 1
to 9 are difficult to be defined.
2) Traditional AHP method is applicable to the
systems with fewer indexes, and when they are used
to the economic model evaluation system, the big
workload will make raters be confused with the
concepts of indexes gradually.
3) Due to current mindset, in 90.1% of the
recovered questionnaires, the top right corner data of
judgment matrix are greater than 1. When some
experts do the rating, they default that the front
index is more important than the afterward indexes.
This kind of mindset leads to an obvious weight
stressed phenomenon in the same layer indexes,
namely the index Content’s weight is greater than
80%, which causes the weight of index Application
APPLICATION OF ANALYTIC HIERARCHY PROCESS ON CALCULATING THE WEIGHTS OF ECONOMIC
MODEL EVALUATION
111