Circuit Tutor®:Prototype of a Mobile Web-based

Intelligent Tutoring System

Tochi Nwachukwu

Brian Butz and Tochi Nwachukwu

Intelligent Systems Application Center (ISAC)

Intelligent Tutoring Systems

An Intelligent Tutoring System (ITS) is any computer system that delivers: • direct customized direction • instruction and feedback to the user• without the involvement of an actual person

Mobile Interface vs. Desktop InterfaceMobile Desktop

Input Small KeyboardMultiple Characters/Keys

Full-size standard keyboard

Interface 3.5-4.5 inch [phones] & 9 inch [tablets] displaySingle-Window design

17+ inch display Multi-Window design

Connectivity Cellular (3G or 4G LTE)/Wi-Fi Ethernet [LAN]/Wi-Fi

Usage Seconds-to-Minutes of useAnytime and Anywhere

Minutes-to-Hours of useClassroom/ Computer Labs

Processors Usually Single/Dual Core Processors Dual/Quad Core Processors

Design Questions• “Does shorter, yet more frequent use of mobile tutors

provide equivalent learning gains compared to longer, yet less frequent, desktop tutor use?”

• “What types of problems are best suited for short and frequent tutor use?”

• “Are the learning gains of the mobile tutor equal to those of the desktop tutor?”

• “Should the ITS app be web-based or native?”

Circuit Tutor®• Objective– develop the prototype of a mobile web-based intelligent

tutoring system (called Circuit Tutor)

• Design– using client-side and server-side scripting tools – HTML5, DHTML,

XML, CSS, JavaScript (handles mathematical computation), PHP (dynamically generated web pages) and Lectora® (Authoring tool).

• Device– iPad® running iOS 4.3 or better– Also runs on iPhone 4 and above

Subsystems

Main Modules• Processing power: Desktop devices > Mobile devices

• Circuit Tutor® will be designed to accommodate that limitation.

• Therefore, NO complex architecture with numerous modules

• Three main units/modules that constantly interact with each other:

The Curriculum UnitThe Problem UnitThe Strategy/Execution Unit

Curriculum Unit• Each section covers a different area of the

undergraduate electrical engineering curriculum (e.g. Equivalent Resistance, Ohm’s Law, Kirchhoff’s Laws [KVL & KCL])

• Every section and subsection consists of different learning objectives

Problem Unit

• This includes questions, answers, and the appropriate knowledge components necessary to solve the questions.

• Problems include:– In-chapter problems (Hints, Feedback etc)– End-of-chapter problems (Knowledge Assessment)– Example problems

Problem Unit• The use of Brown’s Hierarchical Design

method to present problems:

Makes it easy for the ITS to identify the user’s problem area

Determine what next course of action to take

• Computerized Adaptive Testing (CAT) Method for difficulty level adjustment

Brown’s Hierarchical Design Method

• Information is presented to the users:

– are organized in a tree-like fashion,– grouping natural problem solving steps together

on one screen,– thereby allowing the user to answer questions in a

sequenced fashion.

KVL Sample Problem

• What is the voltage across R1?• Every section and subsection consists of different learning

objectives:– First, find the equivalent resistance for R3 and R4? [Learning

Objective I]– Next, determine the KVL equation around the closed circuit.

[Learning Objective II]– Finally, solve for the voltage across R1. [Learning Objective

III]

Strategy/Execution Unit• The strategy unit consists of tutor strategies

and the agenda. Different tutor strategies can make a single problem behave in different fashions.

• This unit will allow for the high-level control of problems and the provision of flow control between problems

Guidelines for Mobile ITS DesignNavigation Minimize the amount of

navigation required by the user to answer questions.

Eliminate navigation required to view entire application screen.

Eliminate need to find support information to utilize the tutoring system.

Guidelines for Mobile ITS Design

Consistency & Compatibility

Interaction with application components should have consistent functions across screens, between and during problems

Interaction required should be compatible with the hardware running the ITS (for example, touch screen using fingers or stylus).

User Session (Username)

Initial Difficulty Level

Pre-Assessment Test

Pre-Assessment Test

Student Placement

Learning Stage (Hints)

End of Learning Stage

Student Knowledge Validation• Two methods are adopted in the prototype

assessment test:

– Hierarchical Design Method (Pinpoint problem area based on Learning Objectives)

– Computerized Adaptive Testing (CAT) Method• Some of the CAT Models examined: GRE, GMAT, NAPLEX

(Pharmacy Test), Linacre’s Dichotomous CAT Test Model

Prototype ITS Assessment Test• Three difficulty levels: Easy, Medium, Difficult

• Each question in the test has a difficulty level and learning objective associated with it (L1D1, L2D2 etc.)

• Starts with Easy difficulty level

• Difficulty level increases only after a set of questions are answered correctly

• Eventually the prototype ITS test will stay at a certain difficulty level

Assessment Test Screen

Assessment Test Screen

Difficulty Increase

Detailed Score Report

Detailed Score Report

Score Interpretation

Circuit Tutor Set-up and Interface• Ad-hoc or FTP connection:– Enter the web link into the mobile browser– The IP address of the server hosting the application is

entered as the web address.

Circuit Tutor Set-up and Interface• Add to home screen:

Circuit Tutor Set-up and Interface• Icon added to homepage