e-Business
An Online Shop in the Area of Technical and Scientific Publications
José António S. Pereira, Paulo Pita, Élsio Santos and Joaquim Filipe
Superior School of Technology, Polithecnical Institute of Setúbal, Rua Vale de Chaves, Setúbal, Portugal
Keywords: e-Commerce, User Profiling, Context-based Software, Machine Learning, Data Mining, Recommender
Systems, Intelligent Systems.
Abstract: The explosive growth of the world-wide-web and the emergence of e-commerce enabled the development
of recommender systems that became to an independent emerged research area in the mid-1990s. The
recommender systems are used to solve the prediction problem or the top-N recommendation problem.
However, recommendation systems feel ever more the pressure related to a change on users habits. In order
to capture users interests it is necessary a representation of information about an individual user. Our Online
Shop in the Area of Technical and Scientific Publications intends to add the best of the user-based
collaborative filtering and content-based collaborative filtering methodologies into a single hybrid
methodology in order to answer some issues raised about new users and new items added to the
recommender system. And also try to combine inference and prediction to assist the user in finding content
that is of personal interest or even combine data mining techniques to provide recommendations.
1 INTRODUCTION
The RS (Recommender systems) became to an
independent emerged research area in the mid-
1990s. And their foundations are based on work
done in the fields of cognitive science, information
retrieval, approximation theory, forecasting theories,
consumer choice modelling in marketing and also
have links to management science (Adomavicius,
G., Tuzhilin, A., 2005).
According to (Deshpande and Karypis, 2004) ,
the recommender systems are personalized
information filtering technology used to either
predict whether a particular user will like a
particular item (prediction problem) or to identify a
set of N items that will be of interest to a certain user
(top-N recommendation problem).
The problem of prediction and recommendation
is increased, because users have their own culture,
expectations, commitments and beliefs, behaving
differently when they act alone or in an organized
way.
In order to capture user’s interests, knowledge,
background, skills, goals, behaviour interaction
preferences, individual characteristics and the user’s
context it is necessary a representation of
information about an individual user (i.e. user
profile) that is essential for the (intelligent)
application we are considering (Schiaffino and
Amandi, 2009).
Another pressure that recommendation systems
feel is related to a change in habits of users, now
more than ever they use e-commerce to make their
purchases, express their views (e.g. commenting,
rating) on collaboration environments and
maintaining links with friends and family; or simply
users with the same preferences.
2 MAIN RS APPROACHES
Most of the researchers agree in the existence of two
main approaches for recommendation systems
item-based analysis and user-based analysis the
first approach determines items that are related to a
specific item (e.g. when a user likes a particular
item, all of which are related are recommended), the
second approach uses personal user information to
suggest the best recommendations (e.g. based on
profile information, user actions, and lists of the
contacts or user's friends) (Patel and Balakrishnan,
2009).
In order to overcome some disadvantages of
approaches exclusively item-based or content-based
289
António S. Pereira J., Pita P., Santos É. and Filipe J..
e-Business - An Online Shop in the Area of Technical and Scientific Publications.
DOI: 10.5220/0004163402890293
In Proceedings of the International Conference on Data Communication Networking, e-Business and Optical Communication Systems (ICE-B-2012),
pages 289-293
ISBN: 978-989-8565-23-5
Copyright
c
2012 SCITEPRESS (Science and Technology Publications, Lda.)
and pure user-based methods of recommendation,
hybrid methods have been created based upon
collaborative filtering and content-based, which
maintains user profiles based on content analysis,
and directly compares these profiles to determine
similar users for collaborative recommendation
(Balabanovic and Shoham, Y., 1997).
To capture the context in which
recommendations are made the multidimensional
approach to recommendations extended to support
additional dimensions capturing the context in which
recommendations are made (Adomavicius and
Tuzhilin, 2001).
All of the work is not only focused on
recommending items to users and users to items, but
takes into consideration additional contextual
information such as time, place, the company of
other people, and other factors affecting
recommendation experiences (Adomavicius et al.,
2005).
Although these different approaches there are
three main recommendation methods, as can be seen
in Figure 1, for finding similar items and similar
users, and can be applied to each of them, techniques
based on heuristics or on models for the rating
estimation (Adomavicius and Tuzhilin, 2005).
Figure 1: Methods used in recommendation systems -
Adapted from: (Adomavicius and Tuzhilin, 2005).
The RS now have the capability to capture
context, through several methods of
recommendation and use of techniques based on
models or heuristics.
To unify user-based and item-based collaborative
filtering approaches (Wang et al., 2006) uses the
similarity fusion. This unification allows the
estimation of final rating by fusing predictions from
three sources: i) predictions based on ratings of the
same item by other users; ii) predictions based on
different item ratings made by the same user; iii)
ratings predicted based on data from other but
similar users rating other but similar items.
The user-based collaborative filtering has been
proven to be the most successful technology for
building recommender systems so far, and is
extensively used in many commercial recommender
systems, although content-based collaborative
recommendation system solves many of the
problems (Patel and Balakrishnan, 2009).
3 OBJECTIVES
The main objective is to develop a website for
electronic commerce oriented to the publication of:
(Scientific Magazines, Books, E-books and
Articles).
Although the existence of several online e-
commerce systems, the purpose is to develop a
flexible website, better than most of the already
existing systems giving each user a different
experience with the online store based on his profile.
The focus is on RS, and should be considered the
several approaches previously mentioned by
focusing on user-based collaborative approach by
applying filtering techniques based on models and
heuristics, putting an emphasis on the user profile.
The differentiating aspect of this system is that it
must be sufficiently intelligent to take the initiative
and proactively recommending the user, content that
we believe is of interest to him.
The user profile must contain essential
information about an individual user and the
motivation of building user profiles is that users
differ in their interest, preferences, backgrounds and
goals when using software applications, discovering
these differences is essential to provide customized
services (Schiaffino and Amandi, 2009).
For the content of the user profile this project
will not only consider the content provided by the
user explicitly, but must infer unobservable
information about users from observable information
about them (Zukerman and Albrecht, 2001).
Figure 2: Predicted observations strategy - Source: (Oard
and Kim, 1998).
It should be combined inference and prediction
to assist the user finding content that is of personal
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interest. This combination helps using implicit
feedback, because it is based on previous
observations, which are used to predict user
behaviour in response to new information, and then
the inference phase seeks in order to estimate the
value of information based on the predicted
behaviour, as Figure 2, shows (Oard and Kim,
1998).
4 DISCOVERY OF THE
FUNCTIONALITIES
To achieve the desired objectives it is necessary to
study the e-commerce competitors and see what kind
of recommendation technology they use.
A comparative study was conducted to analyze
the market and see what other e-commerce sites
have to offer. This comparative study was based on
the direct experience of use.
High-level functionalities have been defined in
order to compare these functionalities between some
of the most popular e-commerce sites. The sites
selected for this study were Amazon.com, FNAC,
Pixmania and Barnes & Noble. Figure 3 shows the
results of the comparison of the functionalities.
Figure 3: Functionalities comparative study.
The results show that Amazon.com has all the
features that our website is intended to have.
In addition to the results, and due to the study by
(Schafer et al., 1999), when he established a
comparison of six e-commerce sites for business,
has allowed a nice overview on the types of
applications used, the interface of recommendation,
recommendation technology and how to find the
recommendations.
As our focus is on Amazon.com as a model to
follow, we show in Figure 4 some of the
applications used to interface recommendation,
recommendation technology and how to find
recommendations.
Figure 4: Amazon.com Recommender System - adapted
from: (Schafer et al., 1999).
This research shows some of the applications
used by Amazon.com.
These applications support the recommendation
of books frequently purchased by customers who
purchased the selected book, recommend authors
whose books are frequently purchased by customers
who buy books by the author of the book selected.
Such applications also do the notification of new
books added to the catalog requests and provide
recommendations based on research performed and
persistent data.
They also offer the possibility of registered users
receive text with recommendations based on the
opinion of other registered users.
Beyond the implementation of these
functionalities mentioned, our website will apply the
implicit feedback techniques to avoid the effort of
cognitive load in assigning precise ratings to large
user populations and thus contributing to avoid the
dispersion of data within these populations. These
techniques seek to avoid this bottleneck inferred
from observations that are available to the system,
something similar to the ratings assigned by a user.
According to (Oard and Kim, 1998) in addition
to explicit ratings were identified three major
categories of potentially useful behavior
observations: examination, retention and reference.
As Figure 5 shows, the category Examination
extends beyond a single interaction between the user
and the system it is characterized by repetition of the
previous user behavior. The category of Retention
aims to group these behaviors that suggest some
future intention to use an object. Finally, the
e-Business - An Online Shop in the Area of Technical and Scientific Publications
291
Reference category is distinguished by the
opportunity to direct observation of negative
evaluations.
Figure 5: Observable behaviour for implicit feedback-
source: (Oard and Kim, 1998).
For the contents of the user profile our website
should have all the information cited above in
Section 1.
Finally our website should not just allow the user
to provide the content about their profile, but also
should be able to infer the information which is not
observable about their profile by using techniques
based on Machine Learning. The user or customer
profile is used to make personalized offers and to
suggest or recommend products the user is supposed
to like (Schiaffino and Amandi, 2009).
5 ISSUES
Taking into account the several approaches and the
main recommendation methods as well as based
techniques, the objectives defined in Section 3 and
the functionalities mentioned in Section 4, many
issues arise.
The companies that use Recommender Systems
in their e-commerce are facing some issues such as:
i) the need to have large amounts of data; ii) based
on the preferences and previous behavior of the user;
iii) the need for a large number of variables.
The first issue is related to the amount of data
and the time required to provide effective
recommendations by RS. It is necessary to save the
data about the items, as well as all user behavior and
profile. The lack of data could become a problem.
This problem is related to the occurrence of a
new user, because it has to rate a sufficient number
of items before a content-based RS can really
understand the user’s preferences and present the
user with reliable recommendations. Therefore, a
new user, having very few ratings, would not be able
to get accurate recommendations (Adomavicius and
Tuzhilin, 2005).
The lack of data is also related to a new item
added to RS, because it relies solely on users
preferences to make recommendations. Therefore,
until the new item is rated by a substantial number
of users, the recommender system would not be able
to recommend it (Adomavicius et al, 2005).
The second issue takes into account trends and
user intentions. Trends are based on past behavior,
and the user can change their tendencies; about the
intentions of the user, it does not always have the
same intentions when browsing a site. The problem
is related to changes in data and user preferences.
The last issue is related to the need of adding
contextual information, and will raise the problem of
complexity because there are a larger number of
variables.
This complexity problem can also be related to a
large retailer that might have huge amounts of data,
tens of millions of customers and millions of distinct
catalog items, and can also be related to old
customers who may have an excess of information
based on thousands of purchases and ratings (Linden
et al., 2003)
6 CONCLUSIONS AND FUTURE
WORK
Although some major issues that have been
mentioned, obviously our web site is by its nature
limited by the peculiarities of the data and the
recommendation domain.
We hope to achieve with this web site an
improvement over existing approaches from the use
of user profiles that contain information about user’s
tastes, preferences, actions and needs.
The profiling information can be elicited from
users explicitly, e.g., through questionnaires, or
implicitly (e.g. learned from their transactional
behavior over time).
We intend to use techniques for content-based
recommendation such as Bayesian classifiers, and
various machine learning techniques, including
clustering, decision trees, and artificial neural
networks.
The methods that we intend to use for searching
similar items and similar users, should apply,
techniques based on heuristics or on models for the
rating estimation.
Even though is no more than an idea, our future
work shall be to find some way of aggregating the
best of the user-based collaborative filtering and
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content-based collaborative filtering methodologies
into a single hybrid methodology.
If the peculiarities of the site allow, this could be
considered an approach based on multidimensional
data model used for data warehousing and OLAP
(Online Analytical Processing) applications in
databases on hierarchical aggregation capabilities,
and on user, item and other profiles defined for each
of these dimensions (Adomavicius et al, 2005).
ACKNOWLEDGEMENTS
We would like to thank the Polytechnic Institute of
Setubal, School of Technology of Setubal, for
supporting the research work reflected in this paper,
presented at ICE-B 2012.
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