when targeted variables contain trend compo-
nents.
(b) The impact of social and economical issues can-
not be reflected.
2. The LM has the next problems.
(a) There are big errors forecasted traffic demands
with the LM, because a correlation between the
traffic demand and the Real GDP has a non linear
correlation.
(b) Forecasting with the LM must be computed over
the available section, then a forecasted traffic de-
mand has no reliability.
Whereas, our new methodology can be reflected the
impact of social and economical events, and will have
smaller errors even if traffic demands contain trend
components.
3 PRESENT OUR MODEL FOR
THE DEMAND FORECAST
This section describes our new model of forecasting
communication traffic demands.
Our model for the demand forecast is defined as the
next equations.
x(i) = x(i − 1) + K(i)Z(i) (1)
K(i) =
X
j
G(e
ij
) (2)
i = 1, 2, . . . , n (3)
The above equation (1) is differential equation.
x(i) is a future value of x, x(i − 1) is a 1 order
past values of x(i), and K(i) means the liveliness of
the society, and is reflected the impact of social and
economical events. In the equation(2), the function
G(e
ij
) evaluates social and economical events e
ij
shown every events e
j
on every periods i. Also in the
equation(1), K(i) is called “K parameter”, because
the society in English means “syakai“ in Japanese,
then we get “K” in spelling of “syakai“. And, by the
same reason, this new model shown as the equation(1)
and equation(2) is called “K model”. Also, Z(i) is the
growth of the Real GDP.
In this K model, a future value x(i) is computed with
a 1 order past traffic x(i − 1) and a K parameter K(i)
and an economical growth Z(i). Also, K(i) is com-
puted with the equation(2), and the function G(e
ij
)
evaluates social and economical events. The function
G(e
ij
) is defined as the next formulas.
G(e
ij
) =
X
k
a
k
g
k
(e
ij
) (4)
The g
k
(e
ij
) means evaluating some aspects
1
k of
e
ij
with the content analysis(Janis, 1965)(Krippen-
dorf, 1980) and the text data mining(Hearst, 1999).
Also a
k
means weighted coefficients. The value of
K(i) increases and decreases by happening social and
economical events e
ij
with the equation(2) and the
equation(4). For example, K decrease by happening
fear events (eg.. the terrorism, the remarkable rise of
the crude oil), and increase by happening relief events
(eg..Olympic Games, the stabilization of the society).
4 EVALUATION
This section describes evaluating the above men-
tioned K model. This evaluation is used the telephone
switching traffic data and GDP data in the USA, be-
cause these data can be gotten easily. Such traffic data
is opened on the Internet during past 20 years.
Thus, we analyse a Dial Equipment Minutes
(DEM) of the Incumbent Local Exchange Carriers
(ILEC)(FCC, ) and the Real GDP chosen from the
National Economic Accounts(BEA, ) in the United
States of America (USA), from 1980 to 2002. Also
targeted K model is built on the R(TheR, 2004).(see
the next section)
4.1 Simulation
This section describes a simulation for the equation(1)
of the above mentioned K model on the R(TheR,
2004) shown as the next paragraph. At this simula-
tion, this K model is simulated from 1980 to 2001.
And a K parameter (shown as Fig.1) is computed and
assumed with a Real GDP and a DEM. By using this
K parameter, simulated DEM (shown as Fig.2)with
the R program (shown as the next paragraph) is good
matched to the real DEM. In this figure, the line is
simulated DEM, and the “x“ is the real DEM. Thus
we can describe past trends with this K parameter. It
is important to study relations among this K parame-
ter and events.
> Kmodel < − function(n){
+ for (i in 2:n){
+ Y [i] < − Y [i − 1] + K.ts[i] ∗ dGDP.ts[i]
+ }
+ return(Y )
+ }
4.2 Survey
This section describes surveying relations between
the K parameter and events which contain social and
1
eg..how widespread on the map, how deep impact on
the psychology
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