recordings 1191 items, the fields is listed as follows
: 1)user_id, unique identification for identifying
each user; 2)sex, representing the gender of user,M
is male and F is female; 3) age, which is calculated
based on user’s birthday; 4) gprs_stream,
representing the consumption of cellular data, it
records the total amount of cellular data user used in
April 2014, and its unit is MB; 5) screen, recording
the screen size of mobile terminal; 6) VIP Class,
there are three user ranks, Silver, Gold, Diamond,
each user belongs to one and only one rank; 7)
brand, which is a dummy variable and represents the
effects of terminal brand, main brands of terminal
equipment contain Apple, Samsung, Nokia, Xiaomi,
Huawei and so on.
According to the terminal type, we divide the
users into phone group and tablet group, and we
conducted a descriptive statistical analysis. In the
phone group, 19.86% of total users are female, and
male accounts for 80.14%. The average screen size
of user’s mobile phone is 4.2 inches, and the average
age of user is 31 year old, in addition, the average
cellular data consumption of user is 264.52 MB in
current month. In the tablets group, female accounts
for 20.74% while the proportion of male is 79.26%.
The average screen size of user’s tablet is 8.7 inches,
and the average age of user is 36 years old, which is
slightly older than the average age of phone group.
Besides, the average cellular data consumption of
user is 595.75 MB in current month. By crossing
analysis, we found that the screen size of user’s
terminal, personal characteristics and brands have an
impact on user’s cellular data consumption.
3 EMPIRICAL RESULTS
In this paper, we carry on linear regressive analysis
based on the overall sample data, mobile terminal
sample data and tablet computer sample data
respectively, and the empirical results are shown in
Table 1. This study carried on regressive analysis
from the user personal level and equipment level, as
is shown in Table 1, the first column is the
dependent variables in the model, and the first row is
the terminal equipment. From the equipment level,
we divide terminal into overall terminals (that is,
cell-phone & tablet computer), cell-phone under 3
inches, cell-phone above 3 inches and tablet
computer. We make 3 inches as a cut-off point for
the screen size of cell-phone, since the screen size of
smart-phone is all above 3 inches, and that of most
non smart-phones is less than 3 inches. Non smart-
phone can only access to the Internet in textual way
and consumes little cellular data, so the smart-phone
is the focus of our research.
The second column in Table 1 presents the
regression results for all equipment. It can be found
that for the overall terminals including cell-phone
and tablet computer, screen size, sex, age, user rank
and brand are all significant to user’s cellular data
usage at the 5% level. The effect of screen size on
cellular data usage is positive, and its standard error
is quite small. With respect to user’s personal
characteristics, the effects of two factors, sex and
age, is negative. That is to say, women’s cellular
data usages are less than men, and the bigger user’s
age is, the more cellular data he consumed. User
rank also affects the cellular data usage significantly,
and the effect is positive, but the standard error is
large (65.647 for the SE of Diamond rank). There is
a significantly positive correlation between terminal
brand and cellular data usage.
The third column in Table 1 presents the
regression results for cell-phone under 3 inches
which is non smart-phone. Because there is no
Diamond rank user among users who use cell-phone
under 3 inches, so the corresponding term is vacant.
As is shown in the table, for non-smart phone,
screen size, age and user rank of Silver are
significant to user’s cellular data usage at the 5%
level, but the effects of user’s sex, brand and user
rank of Gold are not significant. The effect of screen
size on cellular data usage is negative significantly,
which means that for non smart-phone users, the
bigger the screen size of mobile phone is, the less
the cellular data they consume. There is also a
significantly negative correlation between user’s age
and cellular data usage, as users grow older, their
cellular data usage have reduced. The effect of
Silver rank on cellular data usage is significantly
positive, but the error is large.The fourth column in
Table 1 presents the regression results for cell-phone
more 3 inches which is smart-phone. Because there
is no Gold and Silver rank user among users who
use cell-phone above 3 inches, so the corresponding
terms are vacant. As is shown in the table, for smart-
phone, screen size, age, brand and user rank of
Diamond are significant to user’s cellular data usage
at the 5% level, but the effect of sex is not
significant. The effect of screen size on cellular data
usage is significantly positive, and its error is quite
small, which means for smart-phone users, the
bigger the screen size of mobile phone is, the more
the cellular data they consume. There is a
significantly negative correlation between user’s age
and cellular data usage, as users grow older, their
cellular data usage have reduced. The effects of
Relationship between Screen Features of User’s Mobile Terminals and Cellular Data Usage
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