respectively, and the total PC purchase amount is
300,152,151. In <Figure 4>, variables were selected
using a stepwise method as the result of multiple
regression analysis, and the significance level was set
to 0.3 when selecting and removing variables. Finally,
69 independent variables were selected, and the F-
value of the entire regression model and the t-value
for each regression coefficient were also significant
within a given level. At 0.91 and 0.85, the explanatory
power of the variables selected in the regression model
was relatively high. The formula of the finally
constructed model is shown in is the residual analysis
result for the multiple regression model. The
standardized residual chart in <Figure4>(a) shows the
difference between the actual value and the predicted
value, and although some are out of the range, the
difference between the actual value and the predicted
value is mostly included within ±2 range. Therefore, it
can be seen that the predicted values are relatively
accurate. Even in the leverage chart of <Figure
6>(b), which can determine the degree of extreme
bias of explanatory variables, only some occupy a
high influence of 0.9 or higher, but most are evenly
distributed (McClave and Benson, 1985; Neter et al. ,
1985). Calculating the manufacturing PC demand
with the formula for demand forecasting by multiple
regression analysis yields 21.5 billion won.
According to the domestic market demand report of
Gartner, a market research firm released in 2014, the
manufacturing PC demand in 2015 was 21 billion
won. Comparing with the regression analysis results,
it is relatively similar at 98% (Gartner, 2014). The
contribution of this thesis to research from a practical
point of view and an academic point of view can be
divided into two major categories. First, in practice,
new standards and directions to consider when
forecasting demand were presented to B2B marketing
and sales managers. The technique by use considers
four factors that should be looked at from the point of
view of a buyer rather than a seller when forecasting
demand for individual companies, and the multiple
regression analysis method considers the region and
the industry and size of the company when
macroscopically analyzing the B2B commercial area.
Therefore, it was used as an independent variable in
the predictive model. The result of demand
forecasting can be used as an indicator to allocate and
use marketing and sales resources more efficiently for
suppliers, and above all, it can be an objective
standard for regional performance analysis of an
organization (Park et al., 2010). Second,
academically, it is meaningful that the qualitative and
quantitative B2C demand forecasting techniques
presented in various literatures were reflected in the
B2B demand forecasting to derive meaningful results.
As suggested by the Delphi method, the qualitative
method sought expert advice, verified its validity
through sample surveys, and attempted to analyze
demand forecasting in the B2B commercial area
using quantitative methods such as multiple
regression analysis (Ryu, 2013). However, although
there are many manufacturers in Korea, there are
some limitations to the generalization of the proposed
model because only 139 companies were targeted for
the validity of the demand forecasting technique by
use, and multiple regression analysis was performed
using only 2014 data. have it Therefore, we would like
to leave as future tasks the task of improving the
objectivity of the model by securing more data and
the task of constructing a model for various industries
other than manufacturing and other electronic
products other than PC.
5 CONCLUSIONS
In this paper, among the B2B electronic products
market, PC demand forecasting methods were studied
for the private market, where demand forecasting is
relatively difficult compared to the public market. For
this purpose, a qualitative- based demand forecasting
technique for each usage and a quantitative multiple
regression analysis were presented. In the demand
forecasting technique for each use, the demand
calculation formula was derived by dividing the use
into four categories: personal work, common work,
promotion, and welfare, reflecting the opinions of
field experts, and verified for 139 companies. In
addition, multiple regression analysis was performed
by collecting PC purchase amount data by region,
industry, company, and company size, and the
significance of the model was tested through F-value
and t- value tests and residual analysis. Each had
different characteristics, and when it was necessary to
calculate the demand of individual companies, the
demand forecasting technique for each usage was
suggested, and the use of multiple regression analysis
was suggested to predict the size of the entire
domestic PC market. As a result of the demand
forecasting, the standard deviation of the demand
forecasting technique according to the usage was
rather large, but the forecasting rate was found to be
high between 97% and 102%. However, there is a
difference in the forecasting rate for each demand
section, which suggests that it should be applied to
large and small businesses. The result of the demand
forecasting technique by multiple regression analysis
also predicted the PC demand to be 21.5 billion won