to promote engagement in online learning. Perry
(2012) presents a use case to teach speaking style with
word clouds. Miley and Read (2011) used Wordle
(see Feinberg, 2014) to introduce Word Clouds in a
classroom routine, obtaining remarkable results,
validated by the student’s opinions. Finally, also with
Wordle, McNaught and Lam (2010) applied word
cloud tool for content analysis in research. These are
some interesting results of the application of Word
Clouds in teaching and research.
NeuroK is meant to be a social network based
learning platform, and the learning process is
supported by discussions. These interactions motivate
students and engage them. Word cloud tool is
demonstrated to be engaging for the students, and to
motivate them. Kaptein et al. (2010) and Behar-
Horenstein and Niu (2011) established that visual
representations of students texts with a word cloud
improved both critical thinking and engagement,
especially in online discussions. It was tested by
deNoyelles and Reyes-Foster (2015), revealing that
students using word clouds reported moderately
higher scores on critical thinking and engagement, as
well as peer interaction.
In the next sections, NeuroK Word Cloud tool is
presented and the features and results are shown with
examples.
2 IMPLEMENTATION
Today, word clouds have been shown to be a
beneficial tool in many educational environments
(Miley and Read, 2011). They provide a fast visual
representation of the information contained in texts.
In this work, word clouds are built upon a cooperative
e-learning platform, Neurok, to provide an overview
of the main concepts used by the students in their
communications. Thereby, teachers can analyze what
is being talked about in a course and make decisions
on strategy to guide the learning process through the
texts the students write. And since it is a learning
methodology based on the content of
communications, the participation and activity of
students is promoted and supported.
The tool under consideration consists of three
different word clouds: the target cloud, with the
concepts that the teacher would like their students to
talk about; the real cloud, with the concepts most
commonly used by the students; and the mixture of
both, with the target concepts according to their use
by the students. These three word clouds provide a
summary at both topic and course level. Several
metrics to measure the concordance between the
target cloud and the real cloud have also been
implemented.
2.1 Word Cloud
Word clouds represent the concepts most frequently
used by students. In our word cloud representation,
the bigger and more colourful a concept is, the
larger the number of times it is referred to.
The data obtained from NeuroK to build the word
clouds and to compute the concordance are mainly:
Remarks: these are opinions and statements
that a student publishes in a course or topic.
Comments: these are the replies that other
students make of a certain remark.
Rates: these are comments that a student makes
to justify their assessment of a given remark.
Delivery documents: these are the documents
that a student encloses in a delivery. Valid
extensions are .doc, .docx, .pdf, .pptx and .txt.
Each time any of these contents are published in a
course or topic, the corresponding text is
automatically analysed. First of all, words are
extracted from the text and those that do not provide
useful information, such as e-mails, URLs, numbers,
acronyms… are removed from the analysis process.
Once the words have been extracted, they are
analysed one by one checking they are not stop words
and obtaining their stem. Stop words are the most
common words in a language (prepositions, articles,
adverbs, conjunctions, pronouns and some verbs),
whereas a stem is the root form of a word. Stop words
are filtered because they are not so relevant for natural
language processing purposes since they occur
frequently in a language and bring little semantic
value to the content. At present, there is no single
universal list of stop words available, so we have built
our own list. Furthermore, a stemming process based
on Porter Stemming Algorithm (Porter, 1997) is used
for getting the stem words. Other versions of the
algorithm have been included to support more
languages, such as Spanish (Porter, 2001).
Finally, both the analyzed word and those with
which it is related are mapped to the same stem, and
one of them is selected to represent them all. This
avoids repetition of words with the same meaning in
the resultant cloud. When choosing the most
representative word, several criteria are taken into
account: infinitive verb, shorter noun, etc. Words
frequency is counted by stem and only those with the
highest frequency are shown in the cloud.