Adaptive Sequencing of Information for Lifelong Learners - E-Infrastructures and Technologies for Lifelong Learning - page 274

efficient communication mechanisms, adaptation
of mobile communication devices for everytime-
everywhere learning (Brown, 2005; Shudong &
Higgins, 2006), or use of informal resources like
blogs (Klamma et al., 2007), to mention but a few.
There is a significant amount of courses on the
internet, appropriate for all levels from secondary
school to professional training. Initiatives that aim
at complementing traditional classes with online
material or new channels of communication (from
email to voIP) are becoming widespread.
This chapter focuses on the problem of combin-
ing and sequencing learning resources: modularity,
reuse, and recombination are the main goals. Com-
bination and reordering of information define —in
essence— the challenging problem of adaptive
sequencing of learning material. Informally, the
problem of adaptive sequencing can be illustrated
by the process of reading a technical topic (i.e.
not a novel). Technical topics are usually not read
linearly, start-to-end; on the contrary, the readers
rather tend to jump back and forth, according to
their needs and previous knowledge; in many
cases, pages from other topics will also be read
in between. Two different readers will thus fol-
low two different paths, tailored to their needs
and goals. In other words, the original sequence
of the topic is changed into another sequence
adapted to the reader.
The chapter presents an approach to define
adaptive sequencings based on graphs. This ap-
proach has several advantages: it is simple to
understand, and this results in authoring tools that
are easy to use; it is designed for scalability by
using hierarchical structures; it is flexible to allow
cycles in the sequencing to be defined easily; and
it relies on hierarchy and compartmentalization
to facilitate reuse. With respect to this last point,
the chapter will explore the possibility of using
IMS Learning Design as a medium to interchange
adaptive sequencings. The main challenges
involved will be explained, as well as the main
lessons learnt in the process about the limits of
IMS Learning Design.

In other words, the main goal of this chapter
is presenting a viable approach to the problem
of adaptive sequencing definition. The solution
presented is especially appropriate for lifelong
learning scenarios due to its flexibility, simplicity,
and reusability.
The structure of the chapter is as follows. The
next section will present the necessary background
showing the importance of reusability and adap-
tivity for lifelong learning scenarios, as well as
explaining what are the main goals when designing
adaptive sequencing techniques for systems for
lifelong learners. Then, the sequencing graphs
are presented, showing how they fulfill the four
goals presented before. Afterwards, the expres-
sion of sequencing graphs using IMS Learning
Design semantics is discussed, drawing important
conclusions about the limits of this specification.
Finally, the chapter draws the main conclusions
and lines for future work.

BACKGROUND

The Importance of Reuse in LLL

Maybe the strongest force for change in education
has been the massive push that digital technolo-
gies provide for sharing and reusing educational
material. In a digital world, where perfect dupli-
cates are free to generate, educational pieces of
content can be shared with very little to lose and
a lot to gain. Teachers and lecturers all around the
world have started to share educational content:
presentation slides, on-line exercises and tutorials,
or even whole courses (Vest, 2004). This process
has evolved into the concept of Reusable Learning
Objects, or RLO (Wiley & Edwards, 2002; LTSC,
2002), which —in a way— aims at adapting the
object-oriented programming paradigm to the
world of educational material. The concept has
roots in the instructional practice and research
led by the American security forces, which saw
a great development in the middle of the XX