Development and Potential Analysis of Heuristic Evaluation for Educational Computer Game

(PHEG)Hasiah Mohamed @ Omar

Universiti Teknologi MARA (UiTM) Faculty of Computer and Mathematical Sciences,

Dungun Campus, Dungun 23000, Terengganu, Malaysia. hasia980@tganu.uitm.edu.my

Azizah Jaafar Faculty of Information Science and Technology

Universiti Kebangsaan Malaysia 43600 Bangi, Selangor, Malaysia.

aj@ftsm.ukm.my

Abstract—Heuristic Evaluation has expended tremendously from general interface evaluation to more specific evaluation including for computer games application. Computer game plays an important leisure tool nowadays and the potential of it has been explored and being used in teaching and learning. Combination of evaluation method and computer game application that focus on educational purposes, lead to the realization of having comprehensive evaluation method that able to evaluate elements of fun and educational. As a result, Playability Heuristics Evaluation for Educational Computer Game (PHEG) was proposed because of the needs to address important elements especially fun element in educational computer games so that the produced application is fun to be used as well as it incorporates educational elements to help users during the learning process. The development process of PHEG involved five major steps; initial study, proposed heuristics, experts review, evaluation process and final heuristics. The discussions of this paper only focus on the fourth step which is evaluation process on PHEG. At the end of this paper, a potential analysis for PHEG using quantitative method is proposed.

Keywords Heuristics Evaluation, Heuristics Evaluation for Educational Computer Game, Usability, Educational Computer Game

I. INTRODUCTION

Human Computer Interaction (HCI) is a mature field area and usability is one of the main and core concept that emerged from HCI. Scholars defined usability differently based on their studies. Amongst them are: ‘‘the capability to be used by humans easily and effectively’’ [1], ‘‘quality in use’’ [2] and ‘‘the effectiveness, efficiency, and satisfaction with which specified users can achieve goals in particular environments’’ [3]. International Organization for Standardization (ISO) defined usability as “the extent to which the product can be used by specified users to achieve specified goals with

effectiveness, efficiency, and satisfaction in a specified context of use” [3] and it is one of the widely used definitions by researchers. The evolution of usability has been discussed and researched by various scholars and later, they developed various techniques and criteria to conduct usability studies [1, 4, 5, 6, 7, 8, 9] One of the popular technique that being developed by [4] is Heuristics Evaluation (HE).

Heuristics is a design guideline which serve as a useful evaluation tool for booth product designers and usability professional [10]. HE is an inspection evaluation technique that normally being used by an expert to find usability problem in any product or system [10]. HE commonly used for formative evaluation where the product or system 1is still in development process. HE involves a small number of evaluators that has being assigned to inspect a system according to heuristics or guidelines that relevant and focused on the interface of the system. HE is a light-weight process that can be cheap, fast, and easy to apply in evaluation process. It can be used both in design and evaluation phases of development and can even be applied to paper-based designs before the first working prototype is created. HCI studies showed that using five evaluators may be enough to find most usability problems, adding more would reduce the benefit to cost ratio, and suggested that three may suffice [11]. It can be used both in design and evaluation phases of development and can even be applied to paper-based designs before the first working prototype is created. HCI studies showed that using five evaluators may be enough to find most usability problems, adding more would reduce the benefit to cost ratio, and suggested that three may suffice [11]. The HE technique has been emerged from evaluation of software (system and products) to one of the most popular applications nowadays is games [12].

Lately, serious attention of using games in teaching and learning has been discussed among researchers [13, 14,

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15, 16, 17, 18]. A number of games based application has been developed since the realism of the function of computer games in education, training, medical, engineering and lot more [12, 13, 19, 20, 21, 22, 23, 24]. Implementation of computer games for educational purposes need special attention to be considered because integrating of fun (game) and serious (education) is not an easy task for developers and educationist. The intention on integrating games and education in order to increase student motivation in learning is good and practical option if the developed game able to cater all of the necessary elements in education and game. Attention should be focused on ensuring design of the interface and content is really related and relevant for any specific subject to be thought.

In HE, there are a list of heuristics attributes that covers common criteria for any system that focuses on user interface and interaction elements. These elements cover all perspective of system in general, but in terms of educational computer game (ECG), there are no specific heuristics that can cater for all of the elements in ECG such as educational design and contents. Because of this, there is a requirement to have another set of heuristics that focuses on ECG. The argument to the requirement is usability in ECG should cover several elements of education if they are to be applied in teaching and learning formally. Elements of education such as content and educational design should be taken into consideration in evaluation purposes. Therefore, there is a need to construct a list of heuristics for ECG. Thus, the PHEG (Heuristic Evaluation for Educational Computer Game) is developed.

The data, used in PHEG evaluation will be obtained from the results of two analyses, which are quantitative and qualitative. Quantitative analysis is based on statistical functions and countable techniques while qualitative analysis is based on techniques which involve the experience and knowledge of experts or those belonging to knowledge discovery data (KDD) discipline [25]. However this paper is focusing on the quantitative analysis as the potential analysis for PHEG. The analysis is based on the UsabAIPO project which had defined a function, named USABAIPO-H, which is applied in processing quantitative results of Spanish Universities websites heuristic evaluation [25]. As for this study, a function is proposed to process quantitative results of ECG heuristic evaluation. This analysis is expected to give estimation on the usability level of an ECG.

II. THEORITICAL BACKGROUND

A. Heuristics Evaluation Nielsen and Molich [26] introduced a method to be

used with their set of usability guidelines. Heuristic evaluation (HE) is a usability engineering method “for finding usability problem in user interface design by having a small set of evaluators examine the interface and judge its compliance with recognized usability principles (the ‘‘heuristics’’) [26]. The ‘heuristics’ are design guidelines or principles for good interaction design and the aim are to find problematic aspect of the design in order to improve it. This method uses evaluators to find usability problems or violations that may have a deleterious effect on the user to interact with the system.

Typically, these evaluators are experts in usability principles, the domain of interest, or both (so-called ‘‘double’’ experts). Nielsen and Molich [26] described the HE methodology as ‘‘cheap,’’ ‘‘intuitive,’’ ‘‘requires no advance planning,’’ and finally, ‘‘can be used early on in the development process.’’ Often it is used in conjunction with other usability methodologies to evaluate user interfaces [27].

In evaluation process, finding flaws earlier rather than later able to reduce usability errors, which may be more costly to rectify once the application or system is complete. This is when the HE is applicable because of its capabilities to detect errors at early stage with the help of the expert (the evaluators). Indeed, HE also can be used in the spiral or iterative development environment commonly found in the systems design industry.

B. Educational Computer Game (ECG) People play computer games for many reasons.

Amongst them are due to enjoyment and entertaining attributes [28] and for leisure and educational purposes [29]. Generally, Adolescence prefer playing computer games as a leisure time activity, to avoid stress, to challenge their skills and to enjoy the attractive characteristics of the games [30]. Computer games can be effective educational tool [31, 32] and they can provide enjoyment during learning process to learners [30], allow users to engage in education while they enjoying themselves [33, 34, 35].

The aim of educational games is to facilitate the player’s experience [36, 37], desired objective [35], allow users to engage in education while they are enjoying themselves [38, 39]. Educational games seem to put learners in the role of decision maker [18, 28], received immediate feedback of their action and decisions, inviting exploration and experimentation [40].

C. Heuristic Evaluation for Educational Computer Game

Heuristics evaluation shown a huge potential to be a valuable evaluation tool for computer games since the development of HE related to computer games were recorded increasingly started on 1982 until 2008. In 1982, Malone [41] developed a set of guidelines to design enjoyable interfaces based on the study of educational games. Later, in 1998, Clanton [42] developed a set of game design principles. He conducted an informal inspection of several games and his principles were based on that. Clanton’s design principles focus on how computer games can be designed to engage users.

Federoff [17] in 2002 studied on three areas of computer games; game interface, game mechanics and game playability and compiled a list of game heuristics that consist the three areas. Later in 2004, Desurvire et al. [43] developed Heuristics for Evaluating Playability (HEP). HEP has some similarities to the heuristics that being developed by [44]. Korhonen [45] developed playability heuristics for mobile games, based on the demand and popularity usage of mobile games. His heuristics focuses on three areas; game usability, mobility and game play.

In 2007, Song and Lee [46] compiled key factors of heuristics evaluation for game design and categorized game heuristics on four areas; game interface, game play, game narrative and game mechanic. In 2008, Pinelle [47]

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developed heuristics evaluation for video game design that adapt usability inspections for games. His heuristics is specifically focused on game usability and it was based on a structured analysis of usability problem from a large number of games.

TABLE I. HEURISTICS EVALUATION IN COMPUTER GAMES

Author/Year Description Malone, 1982 developed a set of guidelines to design

enjoyable interfaces based on the study of educational games

Clanton, 1998 Developed a set of game design principles. He conducted an informal inspection of several games and his principles were based on that. Clanton’s design principles focus on how computer games can be designed to engage users.

Federoff, 2002 Studied on three areas of computer games; game interface, game mechanics and game playability and compiled a list of game heuristics that consist the three areas.

Desurvire et al., 2004 Developed Heuristics for Evaluating Playability (HEP).

Korhonen, 2006 Developed playability heuristics for mobile games, based on the demand and popularity usage of mobile games. His heuristics focuses on three areas; game usability, mobility and game play.

Song and Lee, 2007 Compiled key factors of heuristics evaluation for game design and categorized game heuristics on four areas; game interface, game play, game narrative and game mechanic.

Pinelle, 2008 Developed heuristics evaluation for video game design that adapts usability inspections for games. His heuristics is specifically focused on game usability and it was based on a structured analysis of usability problem from a large number of games.

D. Quantitative Analysis In quantitative methods, researcher uses tools, such as questionnaires or equipment to collect numerical data and the data is in the form of numbers and statistics [25]. The objective of quantitative analysis is to seek precise measurement and analysis of target concepts using surveys and questionnaires. This method is to classify features, count them, and construct statistical models in an attempt to explain what is observed [25]. In the analysis, researcher knows clearly in advance what he/she is looking for and all aspects of the study are carefully designed before data is collected. Quantitative data is more efficient and able to test hypotheses, but may miss contextual detail [17]. The analysis is recommended during latter phases of research projects. Quantitative methods to evaluate the usability are associated with the search for final results [25][14]. However, currently there is no measurable quantitative measure that is expressive enough to represent concepts as complex as the user satisfaction or the grade where all usability problems in a system can affect its quality [11, 12, 15, and18].

III. DEVELOPMENT OF PHEG

Development of PHEG consists of five major steps; initial study, propose heuristics, expert review, evaluation process and finalize heuristics. Fig. 1 shows the five steps taken in development of PHEG. The discussion of this paper is focus on the step 4, which is evaluation process towards PHEG.

Figure 1: Research Design of PHEG

There are four issues that has been collected and analyzed based on current heuristics and additional criteria gathered from pedagogical elements that normally being used in any computerized system or e-learning. The four issues are interface, pedagogical, content and suitability. Combination of these elements is important for ECG evaluation because its ability to cover overall criteria that play a great impact in ECG development as well as evaluation. Fig. 2 shows the four issues in ECG evaluation.

Figure 2: Educational Computer Game Evaluation Issues.

An educational ECG carries its own criteria that need to be addressed in order to be categorized as an educational ECG. Based on the literature and the encouraging development of heuristics evaluation of educational ECG, it is essential to have another set of heuristic that able to cater evaluation process for educational ECG in specific. The development of Heuristics Evaluation for ECG (PHEG) (initial part) is one of the possible solutions that can be used in order to cater the evaluation issues for ECG. The heuristics proposed by [2, 7, 8] were adapted with minor changes to the wording of some descriptors to facilitate understanding by evaluators some of whom were from non-technical backgrounds.

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A. Proposed PHEG Detailed criteria and descriptions for each of the issues are highlighted in Table 1. The development of initial PHEG will specify on each of the issues, and evaluation of the PHEG will be conducted by suitable and experience expert in specific area, for example expert from educational background will evaluate the heuristic attributes of pedagogical and the subject matter expert will evaluate heuristics attributes of content. All evaluations will be conducted in holistic manner.

TABLE II. DEVELOPED PHEG (INITIAL STAGE)

Usability ECG Usability Heuristics - Interface UI1 Uses aesthetic and minimalist design UI2 Maximizes consistency and matches standards UI3 The uses of space, color and text are according to

the principles of screen design UI4 The uses of text, color and font follow the principles

of readability UI5 Ensure appropriate use of standard and propriety

control UI6 The interactivity of the game is suitable to learners

levelUI7 The integration of presentation means is well-

coordinated UI8 Quality of user interface is acceptable UI9 Provide specific and self- identified key for specific

task (exit, glossary, main, objective) UI10 Overall interface of the game is appealing

Usability ECG Usability Heuristics – EducationalED1 Clear goal and learning objectives ED2 The activities are interesting and engaging ED3 The design and the contents are reliable and proven. ED4 Can be used as self- directed learning tools.ED5 Support for self- learning skills.ED6 Medium for learning by doing. ED7 Considers the individual differences. ED8 Performance should be an outcome-based.ED9 Offers the ability to select the level of difficulty in

games ED10 Ability to work in their own pace

Usability ECG Usability Heuristics - Content CO1 Reliable content with correct flow. CO2 Clear and understandable structure of contents. CO3 Navigation of content is easy and accurate. CO4 Supporting materials are sufficient and relevant

(quiz). CO5 Materials are interesting and engaging. CO6 Players able to understand the learning goal. CO7 The content is chunk based on topic and subtopic CO8 Major and minor topic is differentiate clearly

Usability ECG Usability Heuristics - Playability PL1 Challenge provided are up to the users standard/level PL2 Users able to strategies PL3 The pace of the game are in balance PL4 Players able to control the game PL5 Progress of the game can be seen at anytime PL6 Players able to perform to their best ability PL7 Challenge is adequate – not too easy and not too

difficult Usability ECG Usability Heuristics - Multimedia

MM1 Usage of multimedia elements are acceptable MM2 Combination of multimedia elements are adequate MM3 The presentation of multimedia elements are well

manage MM4 Suitability of multimedia elements for specific use MM5 Not too many multimedia element in one screen MM6 The use of multimedia elements support

meaningfully the text provided.

MM7 The quality of multimedia elements (text, image, animation, video and sound) used is acceptable.

MM8 The uses of multimedia elements enhance the presentation of information.

B. Expert Review on PHEG The proposed PHEG will then be evaluated on the usefulness based on the questionnaire given to the domain expert. The questionnaires are divided into four categories as stated in the Table 2. HCI studies showed that using five evaluators may be enough to find most usability problems, adding more would reduce the benefit to cost ratio, and suggested that three may suffice [6].

Table 2: Questionnaire for Expert Category Number of Question

Clear and understandable term 5Context meaningful to domain. 5Facilitates user's perception on educational computer game design

5

Useful for educational computer game evaluation (formative evaluation)

5

Total 20

IV. EVALUATION PROCESS

A. Potential Analysis This study has produced 43 heuristic attributes for experts which are grouped into 5 categories. The categories are Interface, Educational, Content, Playability and Multimedia. The Interface contains 10 sub-heuristic attributes, Educational also contains 10 sub-heuristic attributes, Content contains 8 heuristic attributes, Playability contains 7 sub-heuristic attributes and Multimedia contains 8 sub-heuristic attributes. Each category was weighted according to its specific range. Table 3 shows the total heuristics and the percentage of heuristic weight according to each category. Based on Table 3, the Interface carries 23%, Educational also carries 23%, Content carries 19%, Playability carries 19% and Multimedia carries 19% heuristic weight.

TABLE III. TOTAL HEURISTIC AND THE PERCENTAGE OF HEURISTIC WEIGHT ACCORDING TO CATEGORY

Category TotalHeuristics

Heuristic Weight (%)

Interface (I) 10 23Educational (E) 10 23 Content (C) 8 19 Playability (P) 7 16Multimedia (M) 8 19 Total Heuristics 43 100

Based on the USABAIPO-H function, a function for ECG heuristic evaluation was proposed as below:

USABPHEG – H(w) = I/0.23 + E/0.23 + C/0.19 + P/0.16+M/0.19

(1)

Where I represent Interface, E is for Educational, C for Content, P for Playability and M for Multimedia. Based

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on the UsabAIPO [25], USABPHEG - H (w) gives an estimation of the degree or level of usability, which is the value of overall usability of the ECG w. Based on the function, it could be emphasized that the evaluation metrics measures usability of ECG, considering how usability is attributed internally. These metrics are summarized into a mathematical formula that provides concrete values regarding usability [25]. Its main advantage lies on its objectivity and clarity to answer key questions that arise in the course of a real life ECG development process [25].

V.DISCUSSION

Our main goal was to develop heuristics that cater on interface, educational, content, playability and multimedia. The developed heuristics were based on the demand of ECG that being used by lot of users especially for educational purposes regardless of their age and gender. Compilation of heuristics for ECG leads to the importance realization of specific heuristics that can be used to evaluate ECG. A potential analysis for ECG heuristic evaluation was also proposed in order to estimate the degree or level of usability, which is the value of overall usability of the ECG.

VI. CONCLUSION

The proposed PHEG need to be further examined and evaluate. The initial PHEG need to be tested and evaluated among the expert based on the highlighted issues in ECG. The potential of PHEG can be further explored once the complete and firm PHEG is developed. The quantitative analysis for ECG heuristics evaluation should also be explored in order to support the result of the heuristic evaluation.

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