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Early mechanical systems
Skinner teaching machine 08
The possibility of intelligent machines have been discussed for centuries. Blaise Pascal created the first calculating machine capable of mathematical functions in the 17th century simply called Pascal's Calculator. At this time the mathematician and philosopher Gottfried Wilhelm Leibniz envisioned machines capable of reasoning and applying rules of logic to settle disputes (Buchanan, 2006). These early works contributed to the development of the computer and future applications.
The concept of intelligent machines for instructional use date back as early as 1924, when Sidney Pressey of Ohio State University created a mechanical teaching machine to instruct students without a human teacher.
His machine resembled closely a typewriter with several keys and a
window that provided the learner with questions. The Pressey Machine
allowed user input and provided immediate feedback by recording their
score on a counter.
Pressey himself was influenced by Edward L. Thorndike,
a learning theorist and educational psychologist at the Columbia
University Teacher College of the late 19th and early 20th centuries.
Thorndike posited laws for maximizing learning. Thorndike's laws
included the law of effect, the law of exercise, and the law of recency.
Following later standards, Pressey's teaching and testing machine would
not be considered intelligent as it was mechanically run and was based
on one question and answer at a time, but it set an early precedent for future projects.
By the 1950s and 1960s, new perspectives on learning were emerging. Burrhus Frederic "B.F." Skinner at Harvard University did not agree with Thorndike's learning theory of connectionism or Pressey's teaching machine. Rather, Skinner was a behaviourist who believed that learners should construct their answers and not rely on recognition.
He too, constructed a teaching machine structured using an incremental
mechanical system that would reward students for correct responses to
questions.
Early electronic systems
In
the period following the second world war, mechanical binary systems
gave way to binary based electronic machines. These machines were
considered intelligent when compared to their mechanical counterparts as
they had the capacity to make logical decisions. However, the study of
defining and recognizing a machine intelligence was still in its
infancy.
Alan Turing,
a mathematician, logician and computer scientist, linked computing
systems to thinking. One of his most notable papers outlined a
hypothetical test to assess the intelligence of a machine which came to
be known as the Turing test.
Essentially, the test would have a person communicate with two other
agents, a human and a computer asking questions to both recipients. The
computer passes the test if it can respond in such a way that the human
posing the questions cannot differentiate between the other human and
the computer. The Turing test has been used in its essence for more
than two decades as a model for current ITS development. The main ideal
for ITS systems is to effectively communicate.
As early as the 1950s programs were emerging displaying intelligent
features. Turing's work as well as later projects by researchers such as
Allen Newell, Clifford Shaw, and Herb Simon showed programs capable of
creating logical proofs and theorems. Their program, The Logic Theorist
exhibited complex symbol manipulation and even generation of new
information without direct human control and is considered by some to be
the first AI program. Such breakthroughs would inspire the new field of
Artificial Intelligence officially named in 1956 by John McCarthy in 1956 at the Dartmouth Conference. This conference was the first of its kind that was devoted to scientists and research in the field of AI.
The PLATO V CAI terminal in 1981
The latter part of the 1960s and 1970s saw many new CAI
(Computer-Assisted instruction) projects that built on advances in
computer science. The creation of the ALGOL
programming language in 1958 enabled many schools and universities to
begin developing Computer Assisted Instruction (CAI) programs. Major
computer vendors and federal agencies in the US such as IBM, HP, and the
National Science Foundation funded the development of these projects.
Early implementations in education focused on programmed instruction
(PI), a structure based on a computerized input-output system. Although
many supported this form of instruction, there was limited evidence
supporting its effectiveness. The programming language LOGO was created in 1967 by Wally Feurzeig, Cynthia Solomon, and Seymour Papert
as a language streamlined for education. PLATO, an educational terminal
featuring displays, animations, and touch controls that could store and
deliver large amounts of course material, was developed by Donald
Bitzer in the University of Illinois in the early 1970s. Along with
these, many other CAI projects were initiated in many countries
including the US, the UK, and Canada.
At the same time that CAI was gaining interest, Jaime Carbonell
suggested that computers could act as a teacher rather than just a tool
(Carbonell, 1970).
A new perspective would emerge that focused on the use of computers to
intelligently coach students called Intelligent Computer Assisted
Instruction or Intelligent Tutoring Systems (ITS). Where CAI used a
behaviourist perspective on learning based on Skinner's theories (Dede
& Swigger, 1988), ITS drew from work in cognitive psychology, computer science, and especially artificial intelligence.
There was a shift in AI research at this time as systems moved from the
logic focus of the previous decade to knowledge based systems—systems
could make intelligent decisions based on prior knowledge (Buchanan,
2006). Such a program was created by Seymour Papert and Ira Goldstein who created Dendral,
a system that predicted possible chemical structures from existing
data. Further work began to showcase analogical reasoning and language
processing. These changes with a focus on knowledge had big implications
for how computers could be used in instruction. The technical
requirements of ITS, however, proved to be higher and more complex than
CAI systems and ITS systems would find limited success at this time.
Towards the latter part of the 1970s interest in CAI technologies began to wane.
Computers were still expensive and not as available as expected.
Developers and instructors were reacting negatively to the high cost of
developing CAI programs, the inadequate provision for instructor
training, and the lack of resources.
Microcomputers and intelligent systems
The
microcomputer revolution in the late 1970s and early 1980s helped to
revive CAI development and jumpstart development of ITS systems.
Personal computers such as the Apple 2, Commodore PET, and TRS-80
reduced the resources required to own computers and by 1981, 50% of US
schools were using computers (Chambers & Sprecher, 1983).
Several CAI projects utilized the Apple 2 as a system to deliver CAI
programs in high schools and universities including the British Columbia
Project and California State University Project in 1981.
The early 1980s would also see Intelligent Computer-Assisted
Instruction (ICAI) and ITS goals diverge from their roots in CAI. As CAI
became increasingly focused on deeper interactions with content created
for a specific area of interest, ITS sought to create systems that
focused on knowledge of the task and the ability to generalize that
knowledge in non-specific ways (Larkin & Chabay, 1992).
The key goals set out for ITS were to be able to teach a task as well
as perform it, adapting dynamically to its situation. In the transition
from CAI to ICAI systems, the computer would have to distinguish not
only between the correct and incorrect response but the type of
incorrect response to adjust the type of instruction. Research in Artificial Intelligence and Cognitive Psychology
fueled the new principles of ITS. Psychologists considered how a
computer could solve problems and perform 'intelligent' activities. An
ITS programme would have to be able to represent, store and retrieve
knowledge and even search its own database to derive its own new
knowledge to respond to learner's questions. Basically, early
specifications for ITS or (ICAI) require it to "diagnose errors and
tailor remediation based on the diagnosis" (Shute & Psotka, 1994,
p. 9). The idea of diagnosis and remediation is still in use today when programming ITS.
A key breakthrough in ITS research was the creation of The LISP
Tutor, a program that implemented ITS principles in a practical way and
showed promising effects increasing student performance. The LISP Tutor
was developed and researched in 1983 as an ITS system for teaching
students the LISP programming language (Corbett & Anderson, 1992).
The LISP Tutor could identify mistakes and provide constructive
feedback to students while they were performing the exercise. The system
was found to decrease the time required to complete the exercises while
improving student test scores (Corbett & Anderson, 1992). Other ITS systems beginning to develop around this time include TUTOR created by Logica in 1984 as a general instructional tool and PARNASSUS created in Carnegie Mellon University in 1989 for language instruction.
Modern ITS
After
the implementation of initial ITS, more researchers created a number of
ITS for different students. In the late 20th century, Intelligent
Tutoring Tools (ITTs) was developed by the Byzantium project, which
involved six universities. The ITTs were general purpose tutoring system
builders and many institutions had positive feedback while using them.
(Kinshuk, 1996)
This builder, ITT, would produce an Intelligent Tutoring Applet (ITA)
for different subject areas. Different teachers created the ITAs and
built up a large inventory of knowledge that was accessible by others
through the Internet. Once an ITS was created, teachers could copy it
and modify it for future use. This system was efficient and flexible.
However, Kinshuk and Patel believed that the ITS was not designed from
an educational point of view and was not developed based on the actual
needs of students and teachers (Kinshuk and Patel, 1997). Recent work has employed ethnographic and design research methods to examine the ways ITSs are actually used by students and teachers across a range of contexts, often revealing unanticipated needs that they meet, fail to meet, or in some cases, even create.
Modern day ITSs typically try to replicate the role of a teacher
or a teaching assistant, and increasingly automate pedagogical functions
such as problem generation, problem selection, and feedback generation.
However, given a current shift towards blended learning models, recent
work on ITSs has begun focusing on ways these systems can effectively
leverage the complementary strengths of human-led instruction from a
teacher or peer, when used in co-located classrooms or other social contexts.
There were three ITS projects that functioned based on conversational dialogue: AutoTutor, Atlas (Freedman, 1999),
and Why2. The idea behind these projects was that since students learn
best by constructing knowledge themselves, the programs would begin with
leading questions for the students and would give out answers as a last
resort. AutoTutor's students focused on answering questions about
computer technology, Atlas's students focused on solving quantitative
problems, and Why2's students focused on explaining physical systems
qualitatively. (Graesser, VanLehn, and others, 2001) Other similar tutoring systems such as Andes (Gertner, Conati, and VanLehn, 1998)
tend to provide hints and immediate feedback for students when students
have trouble answering the questions. They could guess their answers
and have correct answers without deep understanding of the concepts.
Research was done with a small group of students using Atlas and Andes
respectively. The results showed that students using Atlas made
significant improvements compared with students who used Andes.
However, since the above systems require analysis of students'
dialogues, improvement is yet to be made so that more complicated
dialogues can be managed.
Structure
Intelligent
tutoring systems (ITSs) consist of four basic components based on a
general consensus amongst researchers (Nwana,1990; Freedman, 2000; Nkambou et al., 2010):
- The Domain model
- The Student model
- The Tutoring model, and
- The User interface model
The domain model (also known as the cognitive model or expert knowledge model) is built on a theory of learning, such as the ACT-R
theory which tries to take into account all the possible steps required
to solve a problem. More specifically, this model "contains the
concepts, rules, and problem-solving strategies of the domain to be
learned. It can fulfill several roles: as a source of expert knowledge, a
standard for evaluating the student's performance or for detecting
errors, etc." (Nkambou et al., 2010, p. 4). Another approach for developing domain models is based on Stellan Ohlsson's Theory of Learning from performance errors, known as constraint-based modelling (CBM). In this case, the domain model is presented as a set of constraints on correct solutions.
The student model can be thought of as an overlay on the
domain model. It is considered as the core component of an ITS paying
special attention to student's cognitive and affective states and their
evolution as the learning process advances. As the student works
step-by-step through their problem solving process, an ITS engages in a
process called model tracing. Anytime the student model deviates from the domain model, the system identifies, or flags,
that an error has occurred. On the other hand, in constraint-based
tutors the student model is represented as an overlay on the constraint
set. Constraint-based tutors
evaluate the student's solution against the constraint set, and
identify satisfied and violated constraints. If there are any violated
constraints, the student's solution is incorrect, and the ITS provides
feedback on those constraints. Constraint-based tutors provide negative feedback (i.e. feedback on errors) and also positive feedback.
The tutor model accepts information from the domain and
student models and makes choices about tutoring strategies and actions.
At any point in the problem-solving process the learner may request
guidance on what to do next, relative to their current location in the
model. In addition, the system recognizes when the learner has deviated
from the production rules of the model and provides timely feedback for
the learner, resulting in a shorter period of time to reach proficiency
with the targeted skills. The tutor model may contain several hundred production rules that can be said to exist in one of two states, learned or unlearned.
Every time a student successfully applies a rule to a problem, the
system updates a probability estimate that the student has learned the
rule. The system continues to drill students on exercises that require
effective application of a rule until the probability that the rule has
been learned reaches at least 95% probability.
Knowledge tracing tracks the learner's progress from
problem to problem and builds a profile of strengths and weaknesses
relative to the production rules. The cognitive tutoring system
developed by John Anderson at Carnegie Mellon University presents information from knowledge tracing as a skillometer,
a visual graph of the learner's success in each of the monitored skills
related to solving algebra problems. When a learner requests a hint, or
an error is flagged, the knowledge tracing data and the skillometer are
updated in real-time.
The user interface component "integrates three types of
information that are needed in carrying out a dialogue: knowledge about
patterns of interpretation (to understand a speaker) and action (to
generate utterances) within dialogues; domain knowledge needed for
communicating content; and knowledge needed for communicating intent"
(Padayachee, 2002, p. 3).
Nkambou et al. (2010) make mention of Nwana's (1990)
review of different architectures underlining a strong link between
architecture and paradigm (or philosophy). Nwana (1990) declares, "[I]t
is almost a rarity to find two ITSs based on the same architecture
[which] results from the experimental nature of the work in the area"
(p. 258). He further explains that differing tutoring philosophies
emphasize different components of the learning process (i.e., domain,
student or tutor). The architectural design of an ITS reflects this
emphasis, and this leads to a variety of architectures, none of which,
individually, can support all tutoring strategies (Nwana, 1990, as cited
in Nkambou et al., 2010). Moreover, ITS projects may vary according to
the relative level of intelligence of the components. As an example, a
project highlighting intelligence in the domain model may generate
solutions to complex and novel problems so
that students can always have new problems to work on, but it might only
have simple methods for teaching those problems, while a system that
concentrates on multiple or novel ways of teaching a particular topic
might find a less sophisticated representation of that content
sufficient.
Design and development methods
Apart
from the discrepancy amongst ITS architectures each emphasizing
different elements, the development of an ITS is much the same as any instructional design
process. Corbett et al. (1997) summarized ITS design and development as
consisting of four iterative stages: (1) needs assessment, (2)
cognitive task analysis, (3) initial tutor implementation and (4)
evaluation.
The first stage known as needs assessment is common to any
instructional design process, especially software development. This
involves a learner analysis, consultation with subject matter
experts and/or the instructor(s). This first step is part of the
development of the expert/knowledge and student domain. The goal is to
specify learning goals and to outline a general plan for the curriculum;
it is imperative not to computerize traditional concepts but develop a
new curriculum structure by defining the task in general and
understanding learners' possible behaviours dealing with the task and to
a lesser degree the tutor's behavior. In doing so, three crucial
dimensions need to be dealt with: (1) the probability a student is able
to solve problems; (2) the time it takes to reach this performance level
and (3) the probability the student will actively use this knowledge in
the future. Another important aspect that requires analysis is cost
effectiveness of the interface. Moreover, teachers and student entry
characteristics such as prior knowledge must be assessed since both
groups are going to be system users.
The second stage, cognitive task analysis, is a detailed approach
to expert systems programming with the goal of developing a valid
computational model of the required problem solving knowledge. Chief
methods for developing a domain model include: (1) interviewing domain
experts, (2) conducting "think aloud" protocol studies with domain
experts, (3) conducting "think aloud" studies with novices and (4)
observation of teaching and learning behavior. Although the first method
is most commonly used, experts are usually incapable of reporting
cognitive components. The "think aloud" methods, in which the experts is
asked to report aloud what s/he is thinking when solving typical
problems, can avoid this problem.
Observation of actual online interactions between tutors and students
provides information related to the processes used in problem-solving,
which is useful for building dialogue or interactivity into tutoring
systems.
The third stage, initial tutor implementation, involves setting
up a problem solving environment to enable and support an authentic
learning process. This stage is followed by a series of evaluation
activities as the final stage which is again similar to any software
development project.
The fourth stage, evaluation includes (1) pilot studies to
confirm basic usability and educational impact; (2) formative
evaluations of the system under development, including (3) parametric
studies that examine the effectiveness of system features and finally,
(4) summative evaluations of the final tutor's effect: learning rate and
asymptotic achievement levels.
A variety of authoring tools have been developed to support this process and create intelligent tutors, including ASPIRE, the Cognitive Tutor Authoring Tools (CTAT), GIFT, ASSISTments Builder and AutoTutor tools.
The goal of most of these authoring tools is to simplify the tutor
development process, making it possible for people with less expertise
than professional AI programmers to develop Intelligent Tutoring
Systems.
Eight principles of ITS design and development
Anderson et al. (1987) outlined eight principles for intelligent tutor design and Corbett et al. (1997)
later elaborated on those principles highlighting an all-embracing
principle which they believed governed intelligent tutor design, they
referred to this principle as:
Principle 0: An intelligent tutor system should enable the student to work to the successful conclusion of problem solving.
- Represent student competence as a production set.
- Communicate the goal structure underlying the problem solving.
- Provide instruction in the problem solving context.
- Promote an abstract understanding of the problem-solving knowledge.
- Minimize working memory load.
- Provide immediate feedback on errors.
- Adjust the grain size of instruction with learning.
- Facilitate successive approximations to the target skill.
Use in practice
All this is a substantial amount of work, even if authoring tools have become available to ease the task.
This means that building an ITS is an option only in situations in
which they, in spite of their relatively high development costs, still
reduce the overall costs through reducing the need for human instructors
or sufficiently boosting overall productivity. Such situations occur
when large groups need to be tutored simultaneously or many replicated
tutoring efforts are needed. Cases in point are technical training
situations such as training of military recruits and high school
mathematics. One specific type of intelligent tutoring system, the Cognitive Tutor,
has been incorporated into mathematics curricula in a substantial
number of United States high schools, producing improved student
learning outcomes on final exams and standardized tests.
Intelligent tutoring systems have been constructed to help students
learn geography, circuits, medical diagnosis, computer programming,
mathematics, physics, genetics, chemistry, etc. Intelligent Language
Tutoring Systems (ILTS), e.g. this
one, teach natural language to first or second language learners. ILTS
requires specialized natural language processing tools such as large
dictionaries and morphological and grammatical analyzers with acceptable
coverage.
Applications
During the rapid expansion of the web boom, new computer-aided instruction paradigms, such as e-learning and distributed learning, provided an excellent platform for ITS ideas. Areas that have used ITS include natural language processing, machine learning, planning, multi-agent systems, ontologies, semantic Web, and social and emotional computing. In addition, other technologies such as multimedia, object-oriented systems,
modeling, simulation, and statistics have also been connected to or
combined with ITS. Historically non-technological areas such as the
educational sciences and psychology have also been influenced by the
success of ITS.
In recent years, ITS has begun to move away from the search-based to include a range of practical applications.
ITS have expanded across many critical and complex cognitive domains,
and the results have been far reaching. ITS systems have cemented a
place within formal education and these systems have found homes in the
sphere of corporate training and organizational learning. ITS offers
learners several affordances such as individualized learning, just in
time feedback, and flexibility in time and space.
While Intelligent tutoring systems evolved from research in
cognitive psychology and artificial intelligence, there are now many
applications found in education and in organizations. Intelligent
tutoring systems can be found in online environments or in a traditional
classroom computer lab, and are used in K-12 classrooms as well as in
universities. There are a number of programs that target mathematics but
applications can be found in health sciences, language acquisition, and
other areas of formalized learning.
Reports of improvement in student comprehension, engagement,
attitude, motivation, and academic results have all contributed to the
ongoing interest in the investment in and research of theses systems.
The personalized nature of the intelligent tutoring systems affords
educators the opportunity to create individualized programs. Within
education there are a plethora of intelligent tutoring systems, an
exhaustive list does not exist but several of the more influential
programs are listed below.
Education
Algebra Tutor
PAT (PUMP Algebra Tutor or Practical Algebra Tutor) developed by the Pittsburgh Advanced Cognitive Tutor Center at Carnegie Mellon University,
engages students in anchored learning problems and uses modern
algebraic tools in order to engage students in problem solving and in
sharing of their results. The aim of PAT is to tap into a students'
prior knowledge and everyday experiences with mathematics in order to
promote growth. The success of PAT is well documented (ex. Miami-Dade
County Public Schools Office of Evaluation and Research) from both a
statistical (student results) and emotional (student and instructor
feedback) perspective.
SQL-Tutor is the first ever constraint-based tutor developed by the Intelligent Computer Tutoring Group (ICTG) at the University of Canterbury, New Zealand. SQL-Tutor teaches students how to retrieve data from databases using the SQL SELECT statement.
EER-Tutor
is a constraint-based tutor (developed by ICTG) that teaches conceptual
database design using the Entity Relationship model. An earlier version
of EER-Tutor was KERMIT, a stand-alone tutor for ER modelling, whjich
was shown to results in significant improvement of student's knowledge
after one hour of learning (with the effect size of 0.6).
COLLECT-UML
is a constraint-based tutor that supports pairs of students working
collaboratively on UML class diagrams. The tutor provides feedback on
the domain level as well as on collaboration.
StoichTutor
is a web-based intelligent tutor that helps high school students learn
chemistry, specifically the sub-area of chemistry known as
stoichiometry. It has been used to explore a variety of learning science
principles and techniques, such as worked examples and politeness.
Mathematics Tutor
The Mathematics Tutor (Beal, Beck & Woolf, 1998) helps students
solve word problems using fractions, decimals and percentages. The
tutor records the success rates while a student is working on problems
while providing subsequent, lever-appropriate problems for the student
to work on. The subsequent problems that are selected are based on
student ability and a desirable time in is estimated in which the
student is to solve the problem.
eTeacher
eTeacher (Schiaffino et al., 2008) is an intelligent agent or pedagogical agent,
that supports personalized e-learning assistance. It builds student
profiles while observing student performance in online courses.
eTeacher then uses the information from the student's performance to
suggest a personalized courses of action designed to assist their
learning process.
ZOSMAT
ZOSMAT was designed to address all the needs of a real classroom. It
follows and guides a student in different stages of their learning
process. This is a student-centered ITS does this by recording the
progress in a student's learning and the student program changes based
on the student's effort. ZOSMAT can be used for either individual
learning or in a real classroom environment alongside the guidance of a
human tutor.
REALP
REALP was designed to help students enhance their reading comprehension
by providing reader-specific lexical practice and offering personalized
practice with useful, authentic reading materials gathered from the Web.
The system automatically build a user model according to student's
performance. After reading, the student is given a series of exercises
based on the target vocabulary found in reading.
CIRCSlM-Tutor
CIRCSIM_Tutor is an intelligent tutoring system that is used with first
year medical students at the Illinois Institute of Technology. It uses
natural dialogue based, Socratic language to help students learn about
regulating blood pressure.
Why2-Atlas
Why2-Atlas is an ITS that analyses students explanations of physics
principles. The students input their work in paragraph form and the
program converts their words into a proof by making assumptions of
student beliefs that are based on their explanations. In doing this,
misconceptions and incomplete explanations are highlighted. The system
then addresses these issues through a dialogue with the student and asks
the student to correct their essay. A number of iterations may take
place before the process is complete.
SmartTutor
The University of Hong Kong (HKU) developed a SmartTutor to support the
needs of continuing education students. Personalized learning was
identified as a key need within adult education at HKU and SmartTutor
aims to fill that need. SmartTutor provides support for students by
combining Internet technology, educational research and artificial
intelligence.
AutoTutor
AutoTutor
assists college students in learning about computer hardware, operating
systems and the Internet in an introductory computer literacy course by
simulating the discourse patterns and pedagogical strategies of a human
tutor. AutoTutor attempts to understand learner's input from the
keyboard and then formulate dialog moves with feedback, prompts,
correction and hints.
ActiveMath
ActiveMath is a web-based, adaptive learning environment for
mathematics. This system strives for improving long-distance learning,
for complementing traditional classroom teaching, and for supporting
individual and lifelong learning.
ESC101-ITS
The Indian Institute of Technology, Kanpur, India developed the
ESC101-ITS, an intelligent tutoring system for introductory programming
problems.
AdaptErrEx is an adaptive intelligent tutor that uses interactive erroneous examples to help students learn decimal arithmetic.
Corporate training and industry
Generalized Intelligent Framework for Tutoring (GIFT) is an educational software designed for creation of computer-based tutoring systems. Developed by the U.S. Army Research Laboratory from 2009 to 2011, GIFT was released for commercial use in May 2012.
GIFT is open-source and domain independent, and can be downloaded
online for free. The software allows an instructor to design a tutoring
program that can cover various disciplines through adjustments to
existing courses. It includes coursework tools intended for use by
researchers, instructional designers, instructors, and students. GIFT is compatible with other teaching materials, such as PowerPoint presentations, which can be integrated into the program.
SHERLOCK
"SHERLOCK" is used to train Air Force technicians to diagnose problems
in the electrical systems of F-15 jets. The ITS creates faulty
schematic diagrams of systems for the trainee to locate and diagnose.
The ITS provides diagnostic readings allowing the trainee to decide
whether the fault lies in the circuit being tested or if it lies
elsewhere in the system. Feedback and guidance are provided by the
system and help is available if requested.
Cardiac Tutor
The Cardiac Tutor's aim is to support advanced cardiac support
techniques to medical personnel. The tutor presents cardiac problems
and, using a variety of steps, students must select various
interventions. Cardiac Tutor provides clues, verbal advice, and feedback
in order to personalize and optimize the learning. Each simulation,
regardless of whether the students were successfully able to help their
patients, results in a detailed report which students then review.
CODES
Cooperative Music Prototype Design is a Web-based environment for
cooperative music prototyping. It was designed to support users,
especially those who are not specialists in music, in creating musical
pieces in a prototyping manner. The musical examples (prototypes) can be
repeatedly tested, played and modified. One of the main aspects of
CODES is interaction and cooperation between the music creators and
their partners.
Effectiveness
Assessing
the effectiveness of ITS programs is problematic. ITS vary greatly in
design, implementation, and educational focus. When ITS are used in a
classroom, the system is not only used by students, but by teachers as
well. This usage can create barriers to effective evaluation for a
number of reasons; most notably due to teacher intervention in student
learning.
Teachers often have the ability to enter new problems into the
system or adjust the curriculum. In addition, teachers and peers often
interact with students while they learn with ITSs (e.g., during an
individual computer lab session or during classroom lectures falling in
between lab sessions) in ways that may influence their learning with the
software.
Prior work suggests that the vast majority of students' help-seeking
behavior in classrooms using ITSs may occur entirely outside of the
software - meaning that the nature and quality of peer and teacher
feedback in a given class may be an important mediator of student
learning in these contexts. In addition, aspects of classroom climate, such as students' overall level of comfort in publicly asking for help, or the degree to which a teacher is physically active in monitoring individual students may add additional sources of variation across evaluation contexts. All of these variables make evaluation of an ITS complex, and may help explain variation in results across evaluation studies.
Despite the inherent complexities, numerous studies have
attempted to measure the overall effectiveness of ITS, often by
comparisons of ITS to human tutors. Reviews of early ITS systems (1995) showed an effect size of d = 1.0 in comparison to no tutoring, where as human tutors were given an effect size of d = 2.0.
Kurt VanLehn's much more recent overview (2011) of modern ITS found
that there was no statistical difference in effect size between expert
one-on-one human tutors and step-based ITS.
Some individual ITS have been evaluated more positively than others.
Studies of the Algebra Cognitive Tutor found that the ITS students
outperformed students taught by a classroom teacher on standardized test
problems and real-world problem solving tasks.
Subsequent studies found that these results were particularly
pronounced in students from special education, non-native English, and
low-income backgrounds.
A more recent meta-analysis suggests that ITSs can exceed the
effectiveness of both CAI and human tutors, especially when measured by
local (specific) tests as opposed to standardized tests. "Students who
received intelligent tutoring outperformed students from conventional
classes in 46 (or 92%) of the 50 controlled evaluations, and the
improvement in performance was great enough to be considered of
substantive importance in 39 (or 78%) of the 50 studies. The median ES
in the 50 studies was 0.66, which is considered a moderate-to-large
effect for studies in the social sciences. It is roughly equivalent to
an improvement in test performance from the 50th to the 75th percentile.
This is stronger than typical effects from other forms of tutoring.
C.-L. C. Kulik and Kulik’s (1991) meta-analysis, for example, found an
average ES of 0.31 in 165 studies of CAI tutoring. ITS gains are about
twice as high. The ITS effect is also greater than typical effects from
human tutoring. As we have seen, programs of human tutoring typically
raise student test scores about 0.4 standard deviations over control
levels. Developers of ITSs long ago set out to improve on the success of
CAI tutoring and to match the success of human tutoring. Our results
suggest that ITS developers have already met both of these goals....
Although effects were moderate to strong in evaluations that measured
outcomes on locally developed tests, they were much smaller in
evaluations that measured outcomes on standardized tests. Average ES on
studies with local tests was 0.73; average ES on studies with
standardized tests was 0.13. This discrepancy is not unusual for
meta-analyses that include both local and standardized tests... local
tests are likely to align well with the objectives of specific
instructional programs. Off-the-shelf standardized tests provide a
looser fit. ... Our own belief is that both local and standardized tests
provide important information about instructional effectiveness, and
when possible, both types of tests should be included in evaluation
studies."
Some recognized strengths of ITS are their ability to provide
immediate yes/no feedback, individual task selection, on-demand hints,
and support mastery learning.
Limitations
Intelligent
tutoring systems are expensive both to develop and implement. The
research phase paves the way for the development of systems that are
commercially viable. However, the research phase is often expensive; it
requires the cooperation and input of subject matter experts, the
cooperation and support of individuals across both organizations and
organizational levels. Another limitation in the development phase is
the conceptualization and the development of software within both budget
and time constraints. There are also factors that limit the
incorporation of intelligent tutors into the real world, including the
long timeframe required for development and the high cost of the
creation of the system components. A high portion of that cost is a
result of content component building.
For instance, surveys revealed that encoding an hour of online
instruction time took 300 hours of development time for tutoring
content. Similarly, building the Cognitive Tutor took a ratio of development time to instruction time of at least 200:1 hours. The high cost of development often eclipses replicating the efforts for real world application.
Intelligent tutoring systems are not, in general, commercially feasible for real-world applications.
A criticism of Intelligent Tutoring Systems currently in use, is
the pedagogy of immediate feedback and hint sequences that are built in
to make the system "intelligent". This pedagogy is criticized for its
failure to develop deep learning in students. When students are given
control over the ability to receive hints, the learning response created
is negative. Some students immediately turn to the hints before
attempting to solve the problem or complete the task. When it is
possible to do so, some students bottom out the hints – receiving as
many hints as possible as fast as possible – in order to complete the
task faster. If students fail to reflect on the tutoring system's
feedback or hints, and instead increase guessing until positive
feedback is garnered, the student is, in effect, learning to do the
right thing for the wrong reasons. Most tutoring systems are currently
unable to detect shallow learning, or to distinguish between productive
versus unproductive struggle (though see, e.g.). For these and many other reasons (e.g., overfitting of underlying models to particular user populations), the effectiveness of these systems may differ significantly across users.
Another criticism of intelligent tutoring systems is the failure
of the system to ask questions of the students to explain their actions.
If the student is not learning the domain language than it becomes more
difficult to gain a deeper understanding, to work collaboratively in
groups, and to transfer the domain language to writing. For example, if
the student is not "talking science" than it is argued that they are not
being immersed in the culture of science, making it difficult to
undertake scientific writing or participate in collaborative team
efforts. Intelligent tutoring systems have been criticized for being
too "instructivist" and removing intrinsic motivation, social learning
contexts, and context realism from learning.
Practical concerns, in terms of the inclination of the
sponsors/authorities and the users to adapt intelligent tutoring
systems, should be taken into account. First, someone must have a willingness to implement the ITS.
Additionally an authority must recognize the necessity to integrate an
intelligent tutoring software into current curriculum and finally, the
sponsor or authority must offer the needed support through the stages of
the system development until it is completed and implemented.
Evaluation of an intelligent tutoring system is an important phase; however, it is often difficult, costly, and time consuming.
Even though there are various evaluation techniques presented in the
literature, there are no guiding principles for the selection of
appropriate evaluation method(s) to be used in a particular context.
Careful inspection should be undertaken to ensure that a complex system
does what it claims to do. This assessment may occur during the design
and early development of the system to identify problems and to guide
modifications (i.e. formative evaluation).
In contrast, the evaluation may occur after the completion of the
system to support formal claims about the construction, behaviour of, or
outcomes associated with a completed system (i.e. summative
evaluation).
The great challenge introduced by the lack of evaluation standards
resulted in neglecting the evaluation stage in several existing ITS'.
Improvements
Intelligent
tutoring systems are less capable than human tutors in the areas of
dialogue and feedback. For example, human tutors are able to interpret
the affective state of the student, and potentially adapt instruction in
response to these perceptions. Recent work is exploring potential
strategies for overcoming these limitations of ITSs, to make them more
effective.
Dialogue
Human tutors have the ability to understand a person's tone and
inflection within a dialogue and interpret this to provide continual
feedback through an ongoing dialogue. Intelligent tutoring systems are
now being developed to attempt to simulate natural conversations. To
get the full experience of dialogue there are many different areas in
which a computer must be programmed; including being able to understand
tone, inflection, body language, and facial expression and then to
respond to these. Dialogue in an ITS can be used to ask specific
questions to help guide students and elicit information while allowing
students to construct their own knowledge.
The development of more sophisticated dialogue within an ITS has been a
focus in some current research partially to address the limitations and
create a more constructivist approach to ITS.
In addition, some current research has focused on modeling the nature
and effects of various social cues commonly employed within a dialogue
by human tutors and tutees, in order to build trust and rapport (which
have been shown to have positive impacts on student learning).
Emotional affect
A growing body of work is considering the role of affect
on learning, with the objective of developing intelligent tutoring
systems that can interpret and adapt to the different emotional states. Humans do not just use cognitive processes in learning but the
affective processes they go through also plays an important role. For
example, learners learn better when they have a certain level of
disequilibrium (frustration), but not enough to make the learner feel
completely overwhelmed.
This has motivated affective computing to begin to produce and research
creating intelligent tutoring systems that can interpret the affective
process of an individual.
An ITS can be developed to read an individual's expressions and other
signs of affect in an attempt to find and tutor to the optimal affective
state for learning. There are many complications in doing this since
affect is not expressed in just one way but in multiple ways so that for
an ITS to be effective in interpreting affective states it may require a
multimodal approach (tone, facial expression, etc...). These ideas have created a new field within ITS, that of Affective Tutoring Systems (ATS).
One example of an ITS that addresses affect is Gaze Tutor which was
developed to track students eye movements and determine whether they are
bored or distracted and then the system attempts to reengage the
student.
Rapport Building
To date, most ITSs have focused purely on the cognitive aspects
of tutoring and not on the social relationship between the tutoring
system and the student. As demonstrated by the Computers are social actors paradigm humans often project social heuristics onto computers. For example in observations of young children interacting with Sam the CastleMate,
a collaborative story telling agent, children interacted with this
simulated child in much the same manner as they would a human child.
It has been suggested that to effectively design an ITS that builds
rapport with students, the ITS should mimic strategies of instructional
immediacy, behaviors which bridge the apparent social distance between
students and teachers such as smiling and addressing students by name.
With regard to teenagers, Ogan et. al draw from observations of close
friends tutoring each other to argue that in order for an ITS to build
rapport as a peer to a student, a more involved process of trust
building is likely necessary which may ultimately require that the
tutoring system possess the capability to effectively respond to and
even produce seemingly rude behavior in order to mediate motivational
and affective student factors through playful joking and taunting.
Teachable Agents
Traditionally ITSs take on the role of autonomous tutors, however
they can also take on the role of tutees for the purpose of learning by
teaching exercises. Evidence suggests that learning by teaching can be
an effective strategy for mediating self-explanation, improving feelings
of self-efficacy, and boosting educational outcomes and retention.
In order to replicate this effect the roles of the student and ITS can
be switched. This can be achieved by designing the ITS to have the
appearance of being taught as is the case in the Teachable Agent
Arithmetic Game and Betty's Brain.
Another approach is to have students teach a machine learning agent
which can learn to solve problems by demonstration and correctness
feedback as is the case in the APLUS system built with SimStudent.
In order to replicate the educational effects of learning by teaching
teachable agents generally have a social agent built on top of them
which poses questions or conveys confusion. For example Betty from
Betty's Brain will prompt the student to ask her questions to make sure
that she understands the material, and Stacy from APLUS will prompt the
user for explanations of the feedback provided by the student.
Related conferences
Several conferences regularly consider papers on intelligent tutoring systems. The oldest is
The
International Conference on Intelligent Tutoring Systems, which started in 1988 and is now held every other year. The International Artificial Intelligence in Education (
AIED) Society publishes
The International Journal of Artificial Intelligence in Education (IJAIED) and organizes the annual
International Conference on Artificial Intelligence in Education (
http://iaied.org/conf/1/) started in 1989. Many papers on intelligent tutoring systems also appear at
International Conference on User Modeling, Adaptation, and Personalization and
International Conference on Educational Data Mining.
The
American Association of Artificial Intelligence (
AAAI)
will sometimes have symposia and papers related to intelligent tutoring
systems. A number of books have been written on ITS including three
published by Lawrence Erlbaum Associates.