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Chapter 4 : A Framework for an Adaptable and Personalised E-Learning System

4.4 The Knowledge Extraction Model

4.4.2 The Ranking Phase

4.4.2.1 Categorising Learning Outcomes Statements

The suitability of the contents of the selected website should be evaluated to ensure that they

fit the learner’s needs. Matching the content to learning outcomes of curricula is very important when assessing the validity of the selected websites. Basically, learning outcomes are

statements of what a student is expected to know, understand and/or be able to demonstrate

after the completion of the learning process (Kennedy, 2006). Likewise, Mclean and Looker

(2006) described learning outcomes as explicit statements of what we want our students to

know, understand or be able to do as a result of completing our courses. Bloom’s Taxonomy

(Bloom, 1956), is one of the most important and popular frameworks for developing learning

outcomes in order to help students understand what is expected of them. The following sections

explain how to identify learning outcomes, which include Bloom’s Taxonomy and Nouns and

Verbs Extractor.

4.4.2.1.1 Bloom’s Taxonomy

The Bloom’s taxonomy can be used to identify a set of learning outcomes. Typically, a learning

outcome contains a verb and a noun. In one hand, the verb describes the intended cognitive

level of the Bloom’s taxonomy and includes Knowledge, Comprehension, Application, Analysis, Synthesis, and Evaluation. In the other hand, the noun describes specific subject that

student wants to learn. For example: basic structure of the genetic material; nature of

chromosomes and the organisation.

Thus, a set of action verbs was used based on the Bloom’s taxonomy to analyse the learning

outcomes. Furthermore, the Bloom taxonomy identified a list of suitable action verbs into six

levels representing the following cognitive skills: Knowledge, Comprehension, Application,

Analysis, Synthesis, and Evaluation. For example, action verbs such as define, describe and

identify are used to measure basic levels of cognitive skills in comprehension, while action

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measure basic levels of the application cognitive skills. Table 4-1illustrates a set of action verbs

associated with the intended cognitive level of the Bloom’s original taxonomy.

Table 4-1 Set of action verbs associated with the intended cognitive levels of the Bloom’s original taxonomy (Bloom, 1956)

In 2001, a former student of Bloom’s, Lorin Anderson, and a group of cognitive psychologists,

curriculum theorists and instructional researchers, and testing and assessment specialists

published a revision of the Bloom’s Taxonomy entitled A Taxonomy for Teaching, Learning,

and Assessment. The revision updates included significant changes in terminology and

structure. In the revised framework, “action words” or “verbs”, instead of nouns, are used to

label the six cognitive levels, and three of the cognitive levels are renamed. Figure 4-12

illustrates the differences between Bloom’s original taxonomy and the 2001 revised one. Cognitive Level Sample verbs to use in Writing Intended Student learning outcomes

knowledge Define, Identify, Name, Recognize, Retrieve, Duplicate, List, Recall, Reproduce, Tell.

Comprehension Calculate, Conclude, Predict, Discuss, Explain, Classify, Clarify, Translate, Reproduce, Exemplify.

Application Carry out, Demonstrate, Solve , Illustrate, Use, Classify, Execute, Implement, Practice, Utilize.

Analysis Discriminate, Compare, Differentiate, Examine, Infer, Attribute, Contrast, Distinguish, Select, Formulate.

Synthesis Check, Judge, Monitor, Critique, Reconstruct, Defend, Verify, Detect, Coordinate, Dispute.

Evaluation Construct, Design, Compose, Produce, Improve, Create, Invent, Generate, Plan, Combine.

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Figure 4-12 Differences between Bloom’s original taxonomy and the 2001 revised one Table 4-2 A set of action verbs associated with the intended cognitive level of the revised Bloom’s taxonomy (Anderson et al., 2001)

4.4.2.1.2 Nouns and Verbs Extractor

In order to identify learning outcomes statements, first, two types of dictionaries are used. The

action verbs dictionary that contains the action verbs that have been manually defined based

on the Revised Bloom’s taxonomy (Anderson et al., 2001) and the topic name synonym

Noun Form Verb Form

Knowledge

Comprehension

Application

Analysis

Synthesis

Evaluation

Remembering

Understanding

Applying

Analyzing

Evaluating

Creating

Original Taxonomy (1956)

Revised Taxonomy (2001)

Cognitive Level Sample verbs to use in Writing Intended Student learning outcomes

Remembering Define, Identify, Name, Recognize, Retrieve, Duplicate, List, Recall, Reproduce, Tell.

Understanding Calculate, Conclude, Predict, Discuss, Explain, Classify, Clarify, Translate, Reproduce, Exemplify.

Applying Carry out, Demonstrate, Solve , Illustrate, Use, Classify, Execute, Implement, Practice, Utilize.

Analysing Discriminate, Compare, Differentiate, Examine, Infer, Attribute, Contrast, Distinguish, Select, Formulate.

Evaluation Check, Judge, Monitor, Critique, Reconstruct, Defend, Verify, Detect, Coordinate, Dispute.

Creating Construct, Design, Compose, Produce, Improve, Create, Invent, Generate, Plan, Combine.

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dictionary whose terms are retrieved from the ontology. Second, as previously mentioned in

chapter 2, the Stanford CoreNLP (Manning et al., 2014) is used in this research as a tool to

parse learning outcome statements and generate semantic representation in XML format,

including PoS tagging text and a typed dependency representation (see Figure 4-13).

Figure 4-13 Stanford CoreNLP

In addition, the XML format shows data in a tree structure format where tags are assigned for

each word. Theses tags include <root> (governor of sentences), <lemma> (word form), <

sentence id > (sentence number), tokens, word, PoS, parser, dependencies etc. as shown in

Figure 4-14. The Parser tag is very important as it represents the context-free phrase structure

grammar representation, which is used to describe the structure of sentences and words in

natural language that provide the structure derivations of the grammar.

Learning outcomes statement

Parsing Stanford

Parser

XML file

(Noun, Verb, Adverb, Adjective) (nsubj ,nmod advmod, dobj)

Input Conversion & Pre-processing PoS Dependency relation

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Figure 4-14 XML format generated by Stanford CoreNLP

Consequently, from the product of the Stanford parser, all the tokens with the verb tag were

extracted and then check if it matches with a verb from the action verbs dictionary that contains

the action verbs that have been manually defined based on the Revised Bloom’s taxonomy

(Anderson et al., 2001).

A set of rules is used to identify learning outcomes statements by searching the pattern token

in the tagged verb in the action verbs dictionary that have been manually defined based on the

Revised Bloom’s taxonomy in order to identify learning outcomes statement. Table 4-3

<?xml version="1.0" encoding="UTF-8"?>

<?xml-stylesheet href="CoreNLP-to-HTML.xsl" type="text/xsl"?> <root> <document> <sentences> <sentence id="1"> <tokens> <token id="1"> <word>define</word> <lemma>define</lemma> <CharacterOffsetBegin>0</CharacterOffsetBegin> <CharacterOffsetEnd>6</CharacterOffsetEnd> <POS>VB</POS> <NER>O</NER> <Speaker>PER0</Speaker> </token> </tokens>

<parse>(ROOT (S (VP (VB define)))) </parse> <dependencies type="basic-dependencies"> <dep type="root"> <governor idx="0">ROOT</governor> <dependent idx="1">define</dependent> </dep> </dependencies> <dependencies type="collapsed-dependencies"> <dep type="root"> <governor idx="0">ROOT</governor> <dependent idx="1">define</dependent> </dep> </dependencies> <dependencies type="collapsed-ccprocessed-dependencies"> <dep type="root"> <governor idx="0">ROOT</governor> <dependent idx="1">define</dependent> </dep> </dependencies> </sentence> </sentences> </document> </root>

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illustrates the rules that are used to assign learning outcomes based on action verbs in the

Bloom’s taxonomy.

Table 4-3 Rules to assess learning outcomes statement using Bloom’s taxonomy