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Eugenijus Kurilovas et al. Then hierarchical synthesis is used to weight the eigenvectors by the weights of the criteria and the sum is taken over all weighted eigenvector entries corresponding to those in the next lower level of the hierarchy: In order to check the correctness of calculation, having made all the pair-wise comparisons the eigenvalue λ max is calculated: The method of consecutive triple application of AHP consists of application of aforementioned AHP in three consistent stages: Establishment of comparative weights of three different groups of LS quality criteria and weights a i of all quality criteria; Establishment of comparative weights of ‘internal quality’ and ‘quality in use’ criteria groups from activist learner point of view; and Establishment of final weights of quality criteria from activist learners point of view by application of AHP once again only for ‘quality in use’ criteria. 3.2.2 Use of triangular and trapezoidal fuzzy numbers to establish values of quality criteria The widely used measurement criteria of the decision attributes’ quality are mainly qualitative and subjective. Decisions in this context are often expressed in natural language, and evaluators are unable to assign exact numerical values to the different criteria. Assessment can be often performed by linguistic variables: ‘bad’, ‘poor’, ‘fair’, ‘good’ and ‘excellent’. These values are imprecise and uncertain: they are commonly called ‘fuzzy values’. Integrating these different judgments to obtain a final evaluation is not evident (Kurilovas and Serikoviene 2010ab). Therefore, the authors have proposed to use fuzzy group decision making theory (Ounaies et. al. 2009) to obtain final assessment measures. The fuzzy numbers are: (1) triangular fuzzy numbers, (2) trapezoidal fuzzy numbers, and (3) bell-shaped fuzzy numbers (Zhang Li Li and Cheng De Yong 1992, Kurilovas et. al., 2011). In the presented paper, the authors use triangular (Fig. 3) and trapezoidal (Fig. 4) fuzzy numbers for evaluating quality of LS and their suitability to activist learner profile: Figure 3: Triangular fuzzy numbers Figure 4: Trapezoidal fuzzy numbers 386

Eugenijus Kurilovas et al. According to Kurilovas et. al. (2011), in the case of using average triangular fuzzy numbers, linguistic variables conversion into non-fuzzy values of the evaluation criteria should be as follows: ‘excellent’=0.850; ‘good‘=0.675; ‘fair’=0.500; ‘poor’=0.325; ‘bad’=0.150, and in the case of using average trapezoidal fuzzy numbers – ‘excellent’=1.000; ‘good‘=0.800; ‘fair’=0.500; ‘poor’=0.200; ‘bad’=0.000. There are three experts-evaluators (i.e., the authors of the paper) in our case, and therefore it was necessary to calculate average values for each LS quality criterion. 3.3 Practical example of evaluation of learning scenarios in iTEC project Two LS alternatives proposed by iTEC experts were chosen by the authors to demonstrate application of the aforementioned methods for evaluating LS quality and their suitability to chosen activist learner profile: LS1: “A Breath of Fresh Air” (Cycle 1 detailed scenario available at http://itec.eun.org/web/guest/scenario-library ) LS2: “Online Repositories Rock” (Cycle 1 detailed scenario online at http://itec.eun.org/web/guest/scenario-library ) The scenarios do not contain any LOs and there is no explanation of what kind of VLEs should be used to implement the scenarios. Use of particular LOs and VLEs is up to the decision of every country participating in iTEC, and the project experts propose a number of widgets for each scenario to enrich VLEs to be used while implementing scenarios at schools. Therefore, the authors decide to consider ‘good’ LOs only for the chosen LS. This means that all LOs quality criteria in the model presented in Fig. 2 should be evaluated 0.800 according to trapezoidal fuzzy numbers method, and 0.675 – according to triangle fuzzy numbers method. VLE Moodle was chosen by the authors as a proper environment to implement both LS. Since VLE Moodle was already evaluated by the experts in (Kurilovas and Dagiene 2010, 2009a), the authors use the same values to evaluate the VLE component of LS quality criteria. Application of the aforementioned method of consecutive triple application of AHP has shown the following results: Stage 1 (establishment of comparative weights of three different groups of LS quality criteria and weights a i of quality criteria) results have shown that the evaluators prefer LOs and LA components more in comparison with VLE component (LOs – 39.7%, LA – 39.7%, and VLE – 20.6%). Weights a i for all 24 LS quality criteria were also calculated in conformity with AHP. Stage 2 (establishment of comparative weights of ‘internal quality’ and ‘quality in use’ criteria groups from activist learner point of view) results have shown that the evaluators prefer ‘quality in use’ criteria in comparison with ‘internal quality’ criteria (respectively 69.4% Vs 30.6% for LOs, 72.2% Vs 27.8% for LA, and 61.1% Vs 39.8% for VLE) to analyse suitability of chosen LS to activist learners. Stage 3 (establishment of final weights of LS quality criteria from activist learners point of view by application of AHP once again only for ‘quality in use’ criteria) has re-established the weights of ‘quality in use’ criteria. Final evaluation results after using utility function (1) are as follows: In general (G) case when experts do not take into account particular learner profile: 72.7% according to trapezoidal method, or 63.8% according to triangle method for LS1 Vs 68.5% according to trapezoidal method, or 61.0% according to triangle method for LS2: a ⋅ f ( X ) = ( 0, 727 0, 685) a ⋅ f ( X ) = ( 0, 638 0, 610) a iG j iG j In particular case when experts take into account particular (activist) learner (A) profile: 76.4% according to trapezoidal method, or 65.6% according to triangle method for LS1 Vs 69.7% according to trapezoidal method, or 61.8% according to triangle method for LS2: iA ⋅ f ( X j ) = ( 0, 764 0, 697) a iA ⋅ f ( X j ) = ( 0, 656 0, 618) 387

Eugenijus Kurilovas et al.<br />

Then hierarchical synthesis is used to weight the eigenvectors by the weights of the criteria and the<br />

sum is taken over all weighted eigenvector entries corresponding to those in the next lower level of<br />

the hierarchy:<br />

In order to check the correctness of calculation, having made all the pair-wise comparisons the<br />

eigenvalue λ max is calculated:<br />

The method of consecutive triple application of AHP consists of application of aforementioned AHP in<br />

three consistent stages:<br />

Establishment of comparative weights of three different groups of LS quality criteria and weights a<br />

i of all quality criteria;<br />

Establishment of comparative weights of ‘internal quality’ and ‘quality in use’ criteria groups from<br />

activist learner point of view; and<br />

Establishment of final weights of quality criteria from activist learners point of view by application<br />

of AHP once again only for ‘quality in use’ criteria.<br />

3.2.2 Use of triangular and trapezoidal fuzzy numbers to establish values of quality criteria<br />

The widely used measurement criteria of the decision attributes’ quality are mainly qualitative and<br />

subjective. Decisions in this context are often expressed in natural language, and evaluators are<br />

unable to assign exact numerical values to the different criteria. Assessment can be often performed<br />

by linguistic variables: ‘bad’, ‘poor’, ‘fair’, ‘good’ and ‘excellent’. These values are imprecise and<br />

uncertain: they are commonly called ‘fuzzy values’. Integrating these different judgments to obtain a<br />

final evaluation is not evident (Kurilovas and Serikoviene 2010ab).<br />

Therefore, the authors have proposed to use fuzzy group decision making theory (Ounaies et. al.<br />

2009) to obtain final assessment measures. The fuzzy numbers are: (1) triangular fuzzy numbers, (2)<br />

trapezoidal fuzzy numbers, and (3) bell-shaped fuzzy numbers (Zhang Li Li and Cheng De Yong<br />

1992, Kurilovas et. al., 2011). In the presented paper, the authors use triangular (Fig. 3) and<br />

trapezoidal (Fig. 4) fuzzy numbers for evaluating quality of LS and their suitability to activist learner<br />

profile:<br />

Figure 3: Triangular fuzzy numbers Figure 4: Trapezoidal fuzzy numbers<br />

386

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