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Eugenijus Kurilovas et al.<br />

Evaluation of quality of LS alternatives is a typical case where the criteria are conflicting, i.e., LS could<br />

be very qualitative against several criteria, and not qualitative against the other ones, and vice versa.<br />

Therefore, the authors propose to use multiple criteria decision analysis (MCDA) approach for<br />

creation of LS quality evaluation model. In order to construct a proper comprehensive scientific quality<br />

criteria system (model), the authors use the well known principles of identification of quality criteria<br />

that have been proposed by Belton and Stewart (2002) in multiple criteria decision analysis (MCDA)<br />

theory related research work. Practical application of these principles will be described below while<br />

analysing LS quality criteria system (tree).<br />

LS multiple criteria evaluation method used by the authors is referred here as the experts’ additive<br />

utility function represented by formula (1) below including LS evaluation criteria, their ratings (values)<br />

and weights. According to (Kurilovas and Serikoviene 2010b), this method is well-known in the theory<br />

of optimisation methods and is named “scalarisation method”. A possible decision here could be to<br />

transform multi-criteria task into one-criterion task obtained by adding all criteria together with their<br />

weights. Therefore, here we have the experts’ additive utility function:<br />

m<br />

∑<br />

i=<br />

1<br />

f ( X ) = a f ( X ) , a = 1,<br />

a > 0 .<br />

i<br />

i<br />

m<br />

∑<br />

i=<br />

1<br />

i<br />

i<br />

where f i (X j) is the rating (i.e., non-fuzzy value) of the criterion i for the each of the examined LS<br />

alternatives X j. The weights here should be ‘normalised’ according to the ‘normalisation’ requirement<br />

m<br />

∑<br />

i=<br />

1<br />

a = 1,<br />

a > 0 .<br />

i<br />

i<br />

According to (Zavadskas and Turskis 2010), the normalisation aims at obtaining comparable scales of<br />

criteria values. The major is the meaning of the utility function (1) the better LS meets the quality<br />

requirements in comparison with the ideal (i.e., 100%) quality (Kurilovas and Dagiene 2009ab).<br />

The complexity of the analysed problem influences the application of more complex methods for<br />

evaluating the quality of LS from the point of view of different learner groups. In this paper, a novel<br />

method of consecutive triple application of Analytic Hierarchy Process (AHP) is used to establish<br />

proper weights of LS quality criteria in the case when there are several experts evaluators. Triangular<br />

and trapezoidal fuzzy numbers methods are used to establish proper values of LS quality criteria.<br />

After that, formula (1) is used to calculate the values of additive utility functions for each of the<br />

explored LS alternatives.<br />

3. Literature analysis and research results<br />

This section is aimed to apply the aforementioned scientific approaches in order:<br />

To propose a suitable scientific model for evaluation of quality of LS paying especial attention to<br />

their suitability to particular learners’ profiles (i.e., activist learners in our case);<br />

To propose suitable scientific methods for evaluation of quality of LOs paying especial attention to<br />

the use of novel method of consecutive triple application of AHP for establishing quality criteria<br />

weights, and different fuzzy numbers methods to establish the values (ratings) of LS quality<br />

criteria; and<br />

To present the experimental evaluation results using proposed evaluation model and methods.<br />

3.1 Learning scenarios quality model<br />

Belton and Stewart (2002) have identified the following principles of identification of quality criteria<br />

that are relevant to all MCDA approaches: (1) Value relevance; (2) Understandability; (3)<br />

Measurability; (4) Non-redundancy; (5) Judgmental independence; (6) Balancing completeness and<br />

conciseness; (7) Operationality; and (8) Simplicity versus complexity.<br />

LS quality model based on these MCDA criteria identification principles is presented in the Fig. 2. The<br />

model consists of three groups of quality criteria (i.e., components of LS), namely <strong>learning</strong> objects<br />

383<br />

(1)<br />

(2)

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