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Once the learning styles predictor module and the tutorial conversation have been designed, it is necessary to incorporate them into a PCITS architecture. The PCITS will require a number of components, including a CA, a Tutorial Knowledge Base, a Graphical User Interface (GUI) and a Student Model. The components will be described in section 4, which proposes a standard Oscar PCITS architecture that is generic and incorporates the required components.

4 Oscar PCITS Architecture

The Oscar PCITS is independent of a particular learning styles model and of the subject domain being taught. As such, it is important that the Oscar PCITS

architecture allows for the learning styles model and tutoring domain to be changeable by keeping the system knowledge separate from the functionality. Additionally it is important for the adoption of the Oscar PCITS that the

development time of tutorials be minimised. Therefore, a modular architecture is most appropriate as it allows individual modules to be reused and replaced as necessary.

Typical adaptive educational systems contain student, domain, pedagogical and presentation components (Wenger, 1987). A PCITS additionally requires a

conversational agent component that can manage a natural language dialogue. A general expert system architecture (Latham, Crockett & Bandar, 2010) was adapted for the Oscar PCITS. Figure 6.4 shows the proposed generic architecture of

the Oscar PCITS, which has been designed in a modular structure with component reuse in mind. The generic architecture allows alternative tutorial knowledge bases and CA scripts developed following phase 2 of the methodology to be simply

‘plugged in’ to adapt the tutoring to new subjects. Similarly, different learning styles models may be applied by replacing the Learning Styles Predictor component (created following the methodology phase 1).

Controller Graphical User Interface Conversational Agent Learning Styles Predictor Scripts User Student Model Tutorial Knowledge Base

Figure 6.4. Generic Oscar PCITS Architecture

Controller

The controller is the central manager of the system, responsible for

communicating with all components and managing the learner interaction. All communication and information passed between modules passes through the controller. In practice, this component may be combined with the GUI module.

Graphical User Interface (GUI)

The GUI is the user interface, responsible for display, managing events (such as clicking of buttons etc.) and sending communication to and from the user. The display consists of a webpage that provides instructions, displays questionnaires, tests, images, documents, interactive movies and a chat area which is used to communicate with the user. As Oscar PCITS directs the tutoring conversation, no navigation buttons are included as there is no menu system.

The modular nature of the architecture means that the GUI component could be changed to reflect the application needs, such as being deployed as an application on a smartphone or including a speech and voice recognition module.

Student Model

The student model component is responsible for knowing all information about individual students, such as their identifier and password, level of knowledge, topics visited, test scores and learning styles. The student model component receives and sends information from and to the controller about the student. The student model is recorded in a student model database.

Conversational Agent (CA)

The conversational agent component is responsible for accepting natural language text and information about topic and learning style from the GUI, tutorial knowledge base and learning styles predictor components via the controller, and generating a natural language response. The CA accesses a database of conversation scripts (related to but not linked to the tutorial knowledge base) in order to match the input to rules that generate a response. The CA records the dialogue in log files that can be accessed by the controller.

The CA selected must allow information to be passed in and out using variables. Tutorial Knowledge Base

The tutorial knowledge base is responsible for managing course information, such as topics and their breakdowns, related tests and teaching material, which is accessed from a Tutor Material database. All tutor information is related to a

particular tutorial module and will be categorised according to teaching style (related to learning style). The tutorial knowledge base will receive information and

instructions from the GUI, learning styles predictor and CA components via the controller, and will send information to the GUI and CA via the controller.

Learning Styles Predictor

The learning styles predictor component is responsible for accessing information about learning styles and related teaching styles, held in a learning styles database. This component will receive information from the CA, GUI and student model to predict a student’s learning style. Given learning style values from the student model and teaching material values from the knowledge base, this component will apply an adaptation algorithm to determine the most appropriate adaptation for an individual tutorial question. This module is developed by following phase 1 of the Oscar PCITS methodology.

An implementation of the Oscar PCITS architecture will be described in the next chapter, Chapter 7.

5 Conclusion

This chapter has proposed a novel conversational intelligent tutoring system called Oscar that can predict and adapt to an individual’s learning styles whilst directing a tutoring conversation. Natural language interfaces are intuitive for humans, as we use conversation to communicate in real life. A more intuitive and familiar interface for a tutoring system can help learners feel more confident, which can improve their motivation and the effectiveness of their learning. Conversational interfaces can also adopt the constructivist style of tutoring used by human tutors, and thought to aid a deeper understanding of a subject. Oscar PCITS includes the three main intelligent technologies offered by ITS – curriculum sequencing based on individual learning style and existing knowledge, intelligent solution analysis and problem solving support. Implicitly predicting learning style during a tutoring conversation removes the requirement for learners to complete onerous and time- consuming questionnaires. By continually predicting learning style during tutoring, any changes to learning style or differences in learning style for different subjects can be automatically picked up and adapted to. Adapting the tutorial to an

individual’s preferred learning style aids the effectiveness of the learning experience. An original, generic methodology was proposed to construct Oscar PCITS. The three-phase methodology is independent of the learning styles model and tutoring domains selected. Phase 1 of the methodology instructs the development of a

Learning Styles Predictor module, detailing the extraction and analysis of knowledge from the selected learning styles model and the design of logic rules that apply this knowledge for learning styles prediction. A set of generic logic rules were

extrapolated from the logic rules created for the exemplar FS model, which can be applied to other learning styles models as they are based on learner behaviour.

Phase 2 of the methodology directs the design of a tutorial conversation, from the capture of a tutoring scenario to the design of the conversation and scripting of the CA. A three-level model of a tutorial conversation was proposed and a set of generic tutorial question styles and templates developed to allow for quicker development

and more consistent tutorial styles. Finally, phase 3 of the methodology requires the construction of the PCITS architecture.

A generic architecture was proposed for Oscar PCITS, which is modular to allow for component reuse and easier and quicker development and maintenance. The architecture is independent of the choice of learning styles model and the tutoring domain applied.

To validate the proposed generic methodology and architecture for Oscar PCITS, an experimental study is required. The next two chapters will describe an

implementation of Oscar PCITS and experiments conducted to investigate Oscar PCITS’ success in tutoring and predicting learning styles.

6 Chapter Highlights

Oscar CITS is a novel conversational intelligent tutoring system that

automatically predicts and adapts to learning style while directing a tutoring conversation.

Oscar CITS is independent of the learning styles model selected and the tutoring domain.

An original, generic methodology was proposed to construct an Oscar Predictive CITS (PCITS) which can automatically predict learning styles during a tutoring conversation.

Oscar’s innovative predictor module mimics a human tutor by using detected learner characteristics to dynamically predict learning style from a natural language tutoring dialogue.

A set of generic logic rules to predict learning styles was created. A three-level model of a tutorial conversation was proposed.

A set of generic tutorial question styles and templates were developed. A generic, modular architecture for assembling Oscar PCITS was proposed.

1 Introduction

The Oscar Predictive CITS (PCITS) proposed in Chapter 6 can dynamically predict a student‟s learning styles whilst directing a tutorial conversation. A generic methodology and architecture for developing the Oscar PCITS were proposed, which are independent of learning styles model and subject domain. Chapter 5 explored the strategy and methodology for predicting learning styles from a natural language dialogue, using Felder-Silverman (1988) as an example learning styles model.

This chapter will present the development of a prototype Oscar PCITS following the methodology and architecture, and utilising the generic designs, proposed in Chapter 6. The prototype Oscar PCITS delivers a conversational tutorial for the subject domain of the database language Sequential Query Language (SQL). The learning styles model adopted for the prototype Oscar PCITS is the Felder-Silverman (FS) model. In order to validate the methodology and architecture, the prototype Oscar PCITS will then be tested empirically, as described in Chapter 8.

2 Implementing Oscar PCITS

To validate the methodology and architecture proposed in Chapter 6, a prototype Oscar PCITS was implemented. The remainder of this chapter will describe the development of the prototype Oscar PCITS with reference to the 3-Phase Methodology proposed in Chapter 6 and repeated in Table 7.1.

3 Phase 1: Creating the Learning Styles Predictor Module

For the prototype Oscar PCITS, the FS model was adopted (Felder and Silverman, 1988) as it has a small number of dimensions (which is more feasible to implement) and it models the learning styles of engineering students, who will make up the initial experimental groups (see Chapter 5, section 2). Following steps 1.1, 1.2 and 1.3, the FS model was examined to extract the knowledge of behaviour and language traits indicative of learning styles. The resulting knowledge was further analysed, resulting in a table of behaviour characteristics (Table 5.5) and key words (Table 5.6) to be captured during a tutoring conversation. The final step in phase 1 (step 1.4) is to

convert the FS knowledge into a set of logic rules that can continually increment learning style values during tutoring (see Appendix 2). Chapter 5 describes in detail these steps of the methodology and the studies conducted using the FS model.

Table 7.1. 3-Phase Methodology for Creating Oscar PCITS. Phase 1: Create the Learning Styles Predictor Module

1.1.Select a Learning Styles Model

a. Reduce the learning styles model if necessary

b. Extract the behaviour characteristics

1.2.Map learning style behaviour to the conversational tutoring style 1.3.Analyse the learning styles model for language traits

1.4.Adapt the generic logic rules to predict learning styles

Phase 2: Design a Tutorial Conversation

2.1.Capture the tutorial scenario and questions (including movies, voice, images, examples, etc.) from human tutors in a specific domain

2.2.Determine the conversational structure/style

2.3.Map tutorial questions onto the generic question styles and templates

2.4.Script Conversational Agent natural language dialogue for each tutorial question using the 3- level model

2.5.Link tutorial dialogue to logic rules through Conversational Agent variables

Phase 3: Construct the PCITS Architecture

4 Phase 2: Designing the Tutorial Conversation

For the prototype Oscar PCITS the subject domain of the database Sequential Query Language (SQL) was selected. This subject was chosen because the target audience for the pilot study is undergraduate computing students, for whom a Databases course including SQL is compulsory. Additionally, SQL is widely taught in undergraduate computing courses and so the opportunity for reusing an SQL tutorial is high. The tutorial conversation was designed following phase 2 of the methodology, as described in the following sections.

4.1 Step 2.1: Capturing the Tutorial Scenario

The first step in designing a tutorial conversation was to capture knowledge and information from human tutors. The scope of the tutorial was considered first, in terms of its length, the syllabus and learning outcomes. Interviews were conducted with undergraduate level database course tutors to identify important SQL concepts for the tutorial syllabus. It was decided that a revision tutorial for basic SQL would be of most benefit to undergraduate students of several taught units. This decision was based on the fact that basic SQL is taught as part of several units, and included in examinations, however the use of SQL is a skill that may be forgotten if not used regularly. An online revision tutorial would offer students personal assistance in

revising basic SQL at a time and place to suit them, such as during the examination period when formal teaching has ceased.

After taking into account the SQL taught in several unit syllabuses, a syllabus for the revision tutorial was developed which covered some basic SQL commands and concepts. Ten tutorial questions (Table 7.2) and a multiple choice question (MCQ) test (see Appendix 4) were devised to cover the learning outcomes of the tutorial. The syllabus was accepted by SQL lecturers based on their knowledge of student requirements. The MCQ test is required to assess existing knowledge before the start of the tutorial and the same MCQ test is then used to assess learning gain after completion of the tutorial. Twelve questions that test the knowledge and use of SQL covered in the tutorial syllabus were selected from an existing set of MCQ test questions used to support teaching of SQL in the department. The MCQ test was assessed by SQL lecturers who agreed it adequately assessed the learning outcomes from the tutorial syllabus. The syllabus was accepted by SQL lecturers based on their knowledge of student requirements.

To capture the tutorial scenario, a document was produced (called the „tutorial conversation blueprint‟) in consultation with lecturers which contained a

conversation script for each question, including possible learner answers and tutor‟s responses to these. For each learner response, a further tutor response was written, and so on, until each question in the tutorial had a number of different paths

depending on individual learner knowledge and responses. The design of the tutorial conversation was a time consuming and iterative process, however by planning and detailing the dialogue at this point, the development of the conversational agent was more efficient. Resources such as examples, movies, images etc. were embedded into the tutorial conversation as appropriate. The resources were gathered or created where necessary, to support the prediction of various learning styles. Appendix 3 shows an excerpt of the tutorial conversation blueprint document.