Learning Path Construction

If the lecturers have done an adequate job their linear content should be coherent, conclusive, and complete. Hence, if one author’s complete content is presented these requirements are fulfilled. As long as a student is satisfied with the content as presented, there is no need to traverse and find alternative fitting content. The student would expect that a given path is left untouched if there is no reason to behave differently. Additionally, it is dangerous to break the highly complex structure of linear content into pieces and should be avoided as far as possible to not irritate the learner.

Thus the pathfinding strategy is conservative – it tries to leave the linear structure as it is as far as it can in order to present the originally authored path through the content space. Therefore, as a first guess, the pathfinder uses optimistic assumptions as follows: The learner is assumed to

3.3. Implemented Concept • accept each suggested step,

• fulfil all content sections,

• not leave the path by choosing another one, and • stay within the given timeframe.

However, in any case where the expected parameters are not met, the path is adapted to the environment that is parameterised with contexts. Table 4 summarises reasons to alter the original linear structure:

Impact Implication

content section rejected alternative content section content sections omitted shorter

another path chosen prefer another author’s path

duration too long omit content sections

duration too short add content sections

context changed rating changed, maybe context not fulfilled

context not fulfilled alternative path Table 4: Some reasons to alter the original path

It should be remarked that any impacts listed in the table above might also change the contexts and therefore may have a stronger influence on the path creation than the listed implications might indicate. It should also be realised that changing the path rating does not change the created paths themselves, but may push another path into the position of the most preferred path. This changes the path implicitly, because the suggested path has changed. If this is seen in the context of the already presented content sections, this behaviour is put on a level with forking from the initial path.

the repeats: They normally reflect the same structure as the linear source and just uses nested repeats instead of chapters, sections, and so forth. Hence, the repeats describe coherent sequences of content sections. The repeats’ margins are also the margins of these sequences and therefore the preferred positions to branch off.

The following sections give more details on the pathfinding algorithms that create the content sequence. It starts with general determining factors that all the specialised pathfinders have to take into consideration. These specialised pathfinders can be found right after those general factors. Each of them subserve one aspect of the whole pathfinding process. The last section describes the preparations before the paths are presented to the user.

Determining Factors

To avoid repetitions, content sections can be part of the path once at the most. Each content section that has already been presented is stored in a history that enables the learner to rollback. Also content types with at least one fulfilled content section are removed from the path, except of content sections that must be presented and if a content section is needed to fulfil a needed context.

Find Content Sections That Must be Presented

Within a content, structure might be content sections that must be presented. These are either content sections that are weighted with 1, or at least one content section of content types weighted with 1. To create valid paths, all these content sections must be found and incorporated into the paths on the right position, if they are not already included or have already been presented.

Including new content sections may disturb the flow of the original linear structure, because they have not been planned to be integrated. Hence, they should be included as inconspicuously as possible. Good inserting positions are any margins: The beginning or the end of the content or of any repeats. In this case, the content

3.3. Implemented Concept sections to be added are not possible alternatives, but they must be presented. Therefore they should be presented as early as possible, to have a good chance of reacting to any bad impact these insertions might have. Hence, all found content sections that are related should be clustered and added group wise at the beginning of the corresponding sequence. This corresponding sequence is a child of the same repeat or any parent repeat as the subsequently to be added content sections. Create Paths Based on Authors

This is the linear part of the path creation. Beginning with the user’s position, all content sections of content types that have no fulfilled content sections are sorted corresponding to their linear source. Normally, this is each author’s linear content without the already presented parts. The valid paths are sorted and presented to the learner. All invalid paths are handled by the following steps.

Adjust Path duration

If the path’s duration does not fit into the Coherence’s time limits, the path’s length is adjusted. Too long paths are shortened by deleting the worst rated content sections until the duration is less than the maximum. If the path is too short, best rated content sections are added until the duration is more than the minimum. They are inserted like content sections that must be presented, except that they should be inserted at the end of content sequences, because they are alternatives to the linear content.

Solve Impossible Paths

Because of the optimistic path creation strategy, impossible paths might occur. Impossible paths have one or more needed contexts that are not fulfilled. They can be solved with content sections that set (and therefore resolve) the needed contexts.

The best rated of those should be chosen, the following steps are chosen according to the sequencing strategy used:

In case of change and stay, the path should be recreated beginning with the first of them, to keep the structure as linear as possible. It might be needed to repeat this process until all impossible sections are solved.

If change and fall back is used, only the chosen content sections and all additionally required ones should be added to the path. Behind those, the path should be completed with the original selected lecturer’s content, to diverge as little as possible from his content that might be needed to, for example, pass the exams or use the laboratory equipment.

Rate and Sort Paths

To make valuable suggestions to the learner, the paths are sorted regarding their suitability to the history and the current context. The algorithm itself is not the focus of this work, but has been realised for testing and evaluating purposes. As a first possibility, all the parameters that have to be taken into account are averaged using the arithmetic mean. Further details can be found in section 5.3.6 Pathfinder on page 142.

3.4

Summary

Based on the research question and the difficulties of authoring as described in the previous chapter, initially a reason was looked for to explain why authors refuse to accept adaptive concepts and tools, and why they reject thinking in layers and exchangeable content sections as observed by De Bra et al. [20]. Storytelling has given a possible explanation, as it describes the complexity of linear content and that good content is characterised by deep interconnections between the sections of the content through several layers. Additionally, moving a part of the content to

3.5. What’s next another location of the whole content would change its purpose. It seems that it is easier for people to think in these kind of structures.

These insights have lead to a new concept for authoring of adaptive content that is based on the linear structures authors are used to. In contrast to common approaches, it uses only two mandatory layers and one optional layer: One layer that adopts one content structure as is, creating a tree structure from its chapters, sections, etc. The second layer relates content of different authors that is about the same subject by linking similar content sections. The optional layer can be used for refinement by setting weights and conditions. These layers can be completely separated during the authoring process. First, the linear content can be created that includes the content structure. Second, it can be related to another content, creating the second layer. Consequently, this also means that already existing linear content can be used for this approach.

This is followed by a description of how the content can be decomposed and recomposed. Then the components of a system realising the concept are outlined.

The main drawback in respect to multilayer approaches is the lack of detailed control. By using the approach of this research it is only possible to change to another author’s path, including all its dependencies, wording, explanations, etc. However, it would be very beneficial if the concept’s simplifying effects on creation of adaptive content structures would enable and motivate lecturers to create adaptive content.

3.5

What’s next

This chapter has laid the theoretic background of an adaptive content structure concept that is based on authoring for linear content. The following chapter outlines authoring aspects of this concept, including content preparation, import, workflows, and presents a proposal for an authoring environment that supports this concept.

Chapter 4

Authoring Aspects

Based on the concept developed in the previous chapter, the focus here is on its proposed usage by authors. First, a general look is given at adaptive authoring and therefore interactive content and its influences on the definition of authors and authorship. Secondly, an explanation is given of how an existing content structure is transferred to a Coherence structure. Then typical scenarios for collaborative authoring are presented – including how consumers become coauthors. Lastly, an outlook shows how an authoring environment can support work with Coherence structures.

This research only focuses on the concept for the creation of adaptive eLearning content. Besides an editor, no authoring environment has been realised. However, such an environment would be required to profit from the concept’s features. Thus this chapter describes methods and tools that are derived from the concept and should be used as a guideline for further development, and so this chapter describes the practical ideas behind the concept.

4.1

Consequences of Interactivity on Authorship

This section discusses general theoretical aspects of the influence of interactivity on the authorship in respect to this concept, and has been motivated by several

discussions in passing with lecturers which were neither recorded nor analysed, but have been seen to be relevant enough to be mentioned.

Most of these discussions had been partly about authorship and the loss of control of their content. The question raised was who would be the author of adaptive content if students controlled the flow of the presentation. The result of such an adaptive-presented content should be tailored to the student’s needs and can therefore be individual. Because the student influenced the presentation of the work he could be seen as coauthor.

This question is not new. For example, in 1932, Bertolt Brecht stated the following in his radio-theory [21, p 236]:

“Radio broadcasting has to be transformed from a distribution apparatus to a communication apparatus. Radio broadcasting would be the con- ceivably biggest communication apparatus of the public life, [. . . ] if it would know not only how to emit, but also how to receive, thus make the listener not only hear, but also speak and does not isolate him, but establish a relationship.”

Brecht demands that radio broadcasting not only transmit but also receive. Neverthe- less, for him the recipient does not become the producer of the radio transmission and therefore also not the author. The recipient thereby instead becomes an interaction partner of the author rather than (co-) author of the radio transmission. Although Brecht’s radio-theory probably is rather a politically motivated media theory, it already indicates what appears now – 80 years later: The dismantling of the classical mass media model and communication model television station – media – receiver and the softening of the term “author”. However, Brecht does not explain how the new term of “author” has to be defined in a networked world. Therefore, an alternative approach for a network-like structure has to be looked at.

4.1. Consequences of Interactivity on Authorship rhizome. They proclaimed ecstatically that the writing “in this open, (vectored, projective or topological) smooth space in contrast to concluded, (metrical) scalloped space is no more the monologic, linear production of sense, but the cartography of a network, where authors are involved in a variety of varying identities” [117, p 22]. The rhizome describes a network-like and non-linear structure in which a huge number of authors create these nodes. Despite this mention of the large number of authors, interestingly for Deleuze and Guattari the authorship is still indisputable and the term “act” is still valid.

This concept uses inter-textness for its presentation; it establishes references between single content sections. The traditional term act is resolved consciously, because content is no longer a creation in the traditional sense. Nevertheless, an adaptive content contains references and these can be treated as original. Regarding Deleuze’s and Guattari’s statements as to who determines the authors as network creators, the author of a non-linear content is the creator of the content’s network. This point of view is currently of topical interest due to the appearance of Web 2.0 and the shifts in eLearning towards the same changes in eLearning 2.0 [14]. This encourages students to learn by contribution, but it also means that lecturers have to give up some control over their content and how it is used. Their content gets rated, annotated, and meshed with other content. To enable these procedures lecturers have to open their content but many lecturers do not like that idea for various reasons. If this is because of losing control and the difficulties of defining the author for the content, Deleuze’s and Guattari’s definition could help them overcome their reservations and make themselves clearly more equal than the other contributors. If students act as recipients by consuming the content, including interacting with it, and therefore influencing the presentation, the lecturer would be still the author of his content while the students would be interacting partners. As soon as students contribute by meshing and editing content or structures they are authors of their changes, but not of the underlying content. In respect to the adaptive content and

structure as a whole, they should be treated as coauthors. If lecturers control the overall quality, they would be part of the editor team.