Figure 3 shows that recommender engine has the
same importance of searching engines. Both engines
get data from KMS which has the same architecture
as before. We also see that recommender engine
uses the index of searching engines to increase
systemic efficiently.
3.3 User’s Interested Data Collection
It is believe that the more the recommender engine
understands the users the more accurate it can
recommend. So first of all, we adopt recommender
engine in KMS which collects users’ interesting.
There are two methods to collect the data. The first
is explicit method which collects interesting data by
asking the user directly. Sometimes the user gives
his rating to special items or content. The second is
implicit method which collects interesting data by
tracing user’s activities or behavior. This process is
completed automatically, but the implicit data must
be filtered before used to predict because the
behavior can’t reflect the interesting of users.
However, all the users of the KMS have the duty
to contribute their knowledge to KMS. So we can
make some regulations to require users to submit all
the interesting data to the engines. It can not only
increase the accurate of recommender but also
record the collection intelligence in the KMS.
3.4 Security and Privacy
The problem of security of items is also existent in
the recommender engine. To protect the security of
data, a secure architecture is needed to filter the
recommender information. In addition,
recommender engine knows the interests and
behaviors of the users. Most of these data is privacy
and the engine needs to protect those data.
4 RECOMMENDER
TECHNIQUES
The techniques used by recommender engine can be
classified based on the information they use.
According to the features of the academic degree
and postgraduate education, this paper pays more
attention to these recommender techniques as
follows: Rule-based Recommender, Non
personalized-based Recommender, Content-based
Recommender and Collaborative Filtering-based
Recommender.
4.1 Non-personalized Recommender
Non-personalized Recommender is simple because it
uses any information of the users to compute the
recommender items. It recommends items just base
on the importance or popularity of items. The
knowledge management can use these techniques to
push new contents, popular contents and important
contents to each user. All the users are categorized
by department, and the users in same department
may have the same interest. So the engine can
recommend items based on the department.
4.2 Content-based Recommender
Methods use the information about item features and
the ratings a user has given to items (Thomas Hess,
2009).When user searches information in KMS, his
or her behavior is recorded by the Recommender
Engine. The engine uses the individual information
to predict items which have the similar attribute to
the ones preferred in the past. The underlying
assumption of the Content-based Recommender is
that those who interest in the past tend to interest the
similar in the future.
4.3 Collaborative Filtering-based
Recommender
Obviously, both recommender technique discussed
above ignore the contribution from others. And the
collection intelligence is not considered.
Collaborative Filtering-based recommender is used
wildly in most of the e-commerce web sites.
Collaborative filtering is a method of making
automatic predictions about the interests of a user by
collecting taste information from many users. There
are three main techniques can be distinguished: user-
based, item-based, and model-based approaches. But
these approaches can be reduced to two steps:
1. Look for users who share the same rating
patterns with the active user whom the prediction is
for.
2. Use the ratings from those like-minded users
found in step 1 to calculate a prediction for the
active user. The following example of CF explains
how recommender engine works.
If user A likes item A and item B, and user b like
item A and item B, we can discover that user A and
user b have same interest. So if user c likes item c,
we can recommend item c to user A.
In the real recommender engine, all the above
and other approaches are combined together to
provide recommender service. There is an open
APPLICATION OF RECOMMENDER ENGINE IN ACADEMIC DEGREE AND POSTGRADUATE EDUCATION
KNOWLEDGE MANAGEMENT SYSTEM
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