=Paper= {{Paper |id=Vol-3258/article_3 |storemode=property |title=Analysis of Discussion Forum Interactions for Different Teaching Modalities based on Temporal Social Networks |pdfUrl=https://ceur-ws.org/Vol-3258/article_3.pdf |volume=Vol-3258 |authors=Nidia Guadalupe López Flores,María Óskarsdóttir,Anna Sigridur Islind |dblpUrl=https://dblp.org/rec/conf/lak/FloresOI22 }} ==Analysis of Discussion Forum Interactions for Different Teaching Modalities based on Temporal Social Networks== https://ceur-ws.org/Vol-3258/article_3.pdf
Analysis of Discussion Forum Interactions for
Different Teaching Modalities based on Temporal
Social Networks
Nidia Guadalupe López-Flores1 , María Óskarsdóttir1 and Anna Sigriður Islind1
1
    Department of Computer Science, Reykjavik University, Menntavegur 1, 101 Reykjavik, Iceland


                                         Abstract
                                         The temporal component has been pointed out as an impactful dimension for educational research,
                                         as learning is not a static phenomena. In this paper, we investigate how the students’ activity and
                                         interaction dynamics in an online forum differ among teaching modalities. The analysis is based on three
                                         years of forum interaction data in an undergraduate course where the only significant change was the
                                         teaching modality, from on-site (2019) to fully online (2021). We build and analyse temporal networks by
                                         studying changes in several networks’ measures and features. Our preliminary results show changes
                                         in the students’ and teachers’ interaction dynamics as well as changes in the posts’ content with fully
                                         online teaching. This on-going research is focused on studying the impact of teaching modalities on
                                         the discussion forum interactions. Initial results are promising, and other features such as the students’
                                         closeness and betweenness, as well as the dynamics changes’ relationship with the academic performance
                                         are being explored to improve our understanding on teaching modalities and help generalisation of
                                         Network Science and Learning Analytics research in wider educational contexts.

                                         Keywords
                                         Temporal networks, Teaching modality, Online forums




1. Introduction
The education provision has over the course of the last two years, since spring 2020, adapted to
major changes and accelerated technology adoption. The impact of digitally enhanced learning
and teaching, for instance, blended or online formats, has called attention to revision of teaching
methods and modalities [1]. Research on teaching modalities focusing on education components,
for example, achievement of learning outcomes, and analysis of study patterns, has highlighted
the importance of investigating the social element in online teaching settings [2, 3].
   Network analysis is one of the research approaches in Learning Analytics (LA) for analysis
and modelling of relational data in educational settings [4]. Social relationships are an essential
component of learning processes, as they enhance collaboration, skills acquisition, and provide
the learner with social, psychological and academic benefits [5]. Similarly to other real networks,
social networks representing students’ interactions are not static as their connections and
participants change over time. For example, when the students start a course or programme,
Proceedings of the NetSciLA22 workshop, March 22, 2022
Envelope-Open nidia20@ru.is (N. G. López-Flores); mariaoskars@ru.is (M. Óskarsdóttir); islind@ru.is (A. S. Islind)
Orcid 0000-0001-8074-4488 (N. G. López-Flores); 0000-0001-5095-5356 (M. Óskarsdóttir); 0000-0002-4563-0001
(A. S. Islind)
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they might not know all their peers; at first, they could start interacting with a small group of
friends and, as the programme progresses, they could get in contact with other students, because
of academic or personal preferences. Similarly, at the end of the course, some connections
would have vanished if the students stopped interacting at some point during the programme.
   This on-going research focuses on exploring and describing the differences in the usage, con-
tent and interaction dynamics in a discussion forum platform commonly used in undergraduate
courses while taking into account different teaching modalities. We aim to answer the research
question: To what extent does the change in teaching modality impact the usage and interaction
patterns in discussion forum platforms? To answer the question, three years of forum data
were gathered and analysed to outline the changes in interaction dynamics when the modality
of teaching shifted from on-site in 2019, transitioning to emergency remote teaching [6] in
the middle of the term in 2020, to the current new normality with online teaching in spring
2021. The data were analysed using a Social Network approach, by creating three temporal
networks, one per year. All the temporal networks consist of twelve snapshots, each of them
representing the weekly interactions among the students taking part in the forum threads. The
temporal networks were used to compare the changes in the dynamics and evolution of the
group interactions as the term progressed. In addition, the changes in the interaction patterns
and posts’ content were addressed by comparing several indicators, such as posts’ frequency,
length and complexity, week of posting, length of answers’ waiting time, and posts’ answerer 1 .
   The rest of the paper is organised as follows. In Section 2, we present related research on
Social Network Analysis, discussion forums, and temporal networks. In Section 3, we present
the data and the method followed in the study. Finally, in Section 4 we present the preliminary
results obtained, and in Section 5 the discussion and next steps are outlined.


2. Related work
2.1. Discussion forum interactions and Social Network Analysis
Networks are created based on existing relationships among two or more entities, a social
network refers to a collection of people sharing connections within an environment [7]. Social
Network Analysis (SNA) has been used to investigate several aspects of education; in most cases
the students are represented as nodes in the network, and the edges connecting them represent
different kinds of relationships or communication events, either online or face-to-face [4].
Among the educational aspects investigated using SNA, the most common are academic success
and dropout [8, 9], the influence of homophily on performance [10, 11], Massive Open Online
Courses (MOOCs) [12], study patterns [13], course selection [14, 15], collaborative learning [16],
and community detection [14, 17, 18]. Data sources commonly used to construct the networks
include self-reports and surveys in face-to-face settings, as well as discussion logs and threads
in online events and forums for online networks. In regards of forum interactions, Poquet [19]
investigated the effect of enrolment, course design, and individual learner characteristics in
performance-base similarity in online discussion forums in higher education. Xu et al. [20]
applied SNA to analyse the effect of the content of forum posts on the connections among

   1
       In describing this data, an answerer is any participant of the course that provides answers to the forum threads.
students participating in MOOCs. Gitinabard et al. [21] used online discussion forum data
to analyse the correlation among network metrics and student performance. Their findings
show that students who asked more questions and received more feedback got higher grades.
Similarly, Williams-Dobosz et al. [22] applied SNA to examine the connection among learning
performance and help seeking. Their studies also concluded that connectivity per se does not
have a direct influence on learning outcomes achievement.

2.2. Temporal networks
Temporal networks, (i.e., networks where the nodes’ connections change over time) are useful
for modelling the dynamic behaviour of many complex real-world systems because their inter-
actions are rarely constant over time [23, 24]. Considering the moment when the connections
happen when creating networks has an impact on several properties and measures, such as con-
nectedness, shortest paths, and centrality [25]. Evolution over time is an important dimension in
learning processes. Consequently, in the latest years, the attention paid to the temporality and
its effects on learning has increased; focusing on varied elements of educational settings [26, 27].
Saqr et al. [28] studied the role of temporal measures for predicting academic performance;
their findings underline that the temporal dimension provides essential information on learning
patterns and can potentially support instructors in addressing students’ performance. Xu et al.
[12] implemented SNA and community detection algorithms over data from an 8-week MOOCs
course to study the moment when most connections among the students enrolled happen.
In their study, most of the connections and communities were created during the first two
weeks of the course and evidence of performance homophily was found between the students
and their closest friends at the end of the course. Vörös et al. [29] reported on the collection
methodology of a longitudinal data set of undergraduate students, collected from 2016 to 2019.
In their study, the undergraduate students answered a set of short and long surveys related
to social connections, individual background and study behaviour during the three years of
their undergraduate studies. Data from social media platforms and two field experiments were
also gathered to complement the surveys’ answers. Shirvani et al. [30] based their research
on online discussion forums in two MOOCs offered by Coursera to analyse the content and
social structure dynamics and temporal patterns. Their research shows that activity levels can
be predicted one week in advance using the information in the temporal networks.


3. Methods
3.1. Data
This study encompasses the discussion forum interaction data of one undergraduate course from
2019 to 2021. The course is a first-year course for the computer science programme at Reykjavik
University and a second year course for the engineering programme. The course is always
taught in the spring term, with a high number of students enrolled each year: 215, 233 and 318
students respectively. The main characteristic of this case study is that during the three years
included, most of the course’s features remained without changes. The course had the same
teacher, syllabus, book, assessment structure, and an active online discussion forum available for
the students’ use. The only component with significant changes was the teaching modality. In
2019, the teaching was delivered on-site at the university premises. In 2020 it started on-site, but
due to the meeting restrictions imposed as response to the COVID-19 pandemic outbreak, the
teaching modality was suddenly moved to online learning at the beginning of March. Finally,
in 2021, the course was planned and delivered completely online.
   The data were gathered from Piazza, an online discussion forum platform widely used
among undergraduate courses to support and enhance student-student and student-instructor
communication. In this course, the students were allowed to post questions, notes, and polls to
the forum participants registered in the course section in Piazza. In addition, they were able to
post answers, updates and follow-up questions to any public post previously published. The
discussion forum was included into the course settings with the intention to: (1) encourage
the students to collaborate with their classmates, and (2) provide the students with a direct
communication channel with the instructors (teacher and teaching assistants). Neither their
registration into the course section nor their participation in the threads were mandatory or
included in the assessment structure. In addition, categorical grade placements from A to D
were created based on the numerical grades obtained from the Learning Management System.
Students with outstanding performance were allocated in A grade placement, whereas students
who did not pass the course were allocated in D grade placement.

3.2. Network construction and analysis
To answer our research question, the analysis performed includes two components. The first
component, the social network analysis is included with the objective of studying the evolution of
communication events along the term and compare it across years and teaching modalities. The
second component, related to posts’ content features, complements the social networks analysis
and is useful to get a better understanding of the differences between teaching modalities. Table
1 displays the features included in the posts’ content analysis.
   For the network analysis, the networks were created based on the edge list created using the
forum threads archive, as described in Figure 1. Each node in the network represents a forum
participant (teacher, teaching assistant, or student). The categorical grade placements were
included in the network as an attribute of each student node.
   As noted above, the interaction network in the discussion forum is dynamic, since not all
participants registered are present since the beginning, and more edges are added as the course
progresses. Representing dynamic interactions as networks can be addressed in several ways
[31]. In this study, following the syllabus structure and the asynchronous dynamic on the
online discussion forum; we decided to create twelve static networks per year. Each network
represents one week of interactions between the participants (See Fig. 2). The networks were
created based on the post’s timestamp to analyse their growth and their features’ evolution
during the term; and compare them among teaching modalities to study their differences. Table
2 displays the network measures that were calculated and analysed for all years and networks
created. The data pre-processing and social network analysis were conducted in Python using
the NetworkX package.
Figure 1: Network creation based on the Piazza threads. Left: Forum discussion structure. Any new
thread starts with a question, note or poll published by students or instructors. Any participant can
post an answer, follow-up question, or updates. Right: Directed edges in the network are created from
participants who posted answers, follow-up questions, or updates (Nodes B and C) to questions, notes
or polls posted by any other participant (Node A). The weight of each link is calculated by accumulating
the number of times one node (source) answered to another (target).




Figure 2: Temporal networks created based on 2021 posts in weeks 1, 6, and 12. The nodes are coloured
based on categorical grade placement obtained: A (red), B (blue), C (green), D (purple), No grade (orange).
The teacher and teaching assistants are yellow and brown respectively. The nodes are sized according
to the number of contributions posted each week.


4. Preliminary results
Figure 3 displays the weekly evolution of the network measures presented in Table 2. The
exploratory analysis on the networks’ structure reveals differences in the students’ and teachers’
activity among the modalities of teaching. Those results, combined with the analysis of the
posts’ features and the platform usage among years, lead to the first insights about the effect of
the change in the teaching modality between years. These insights can be split into students,
instructors and comments’ structure conclusions.
  For the students:
   1. With fully online teaching, a higher proportion of students registered in the forum
      platform.
   2. The percentage of active students increased from 41% and 52%, to 66% in 2021.
   3. Active students had on average grades 35% higher than non-registered and observer
      students in online teaching, whereas with on-site teaching the increment was 5%, and
      15% in the transition in 2020.
Table 1
Set of features analysed in the posts’ content component.
            Feature
            Length of the first post in each thread
            Number of unique words within the post
            Whether the post was published anonymously or not
            Time in weeks until a student’s first post or contribution
            Time in hours until the first answer received to each post
            Follow-up questions in each thread
            Number of answers provided by the teacher, teaching assistants, and students


Table 2
List of network measures computed and analysed in the first component and their meaning in the
context of the discussion forum network.
  Measure                    Meaning in the discussion forum’s network context
  No. of nodes               Number of students taking part in the forum threads by posting or
                             answering threads.
  No. of edges               Number of unique edges as an indicator of how active the participants
                             are by contacting different participants each week.
  Size                       Weight assigned to the edges as an indicator of how strong the connec-
                             tions are. The more communication events occur between each pair of
                             participants, the higher the size will be.
  In-degree                  Number of peers answering a student’s post as an indicator of the
                             nodes’ posts popularity.
  Out-degree                 Number of peers the student answered to by posting an answer or
                             follow-up question.
  Density                    Number of posts relative to the number of possible students’ connec-
                             tions as an indicator of the network’s completeness.
  Clustering coefficient     Proportion of a nodes’ friends answering to each other, as an indicator
                             of how tightly connected the students are.
  Teacher’s betweenness      Teacher’s influence on the information spreading among the course
                             participants.


   4. The networks of fully online teaching grew faster than with the other modalities, as
      a result of a higher percentage of students participating in the forum each week; the
      number of unique connections and contributions was also higher.
   5. In 2021, with a higher average in-degree, out-degree, and clustering coefficient; the
      students got in contact with more people and were more connected with their close peers.
   6. In fully online teaching, there was no difference in the week when the students started
      posting questions on the platform, in contrast to previous years, when D students started
      posting later in the term.
   7. The students were more involved in the discussion threads, the number of follow-up
      questions posted increased in 2021.
  In regards to the instructors’ activity, in 2021 with fully online teaching:
 (i) Number of nodes par-    (ii) Unique edges            (iii) Size          (iv) Average in-out de-
     ticipating                                                                    gree




             (v) Density             (vi) Average clustering           (vii) Teacher’s between-
                                          coefficient                        ness
Figure 3: Weekly evolution of the temporal network’ measures displayed on Table 2 from 2019 to 2021.


   1. The teacher’s betweenness indicates the influence on the spreading of information among
      the students was stronger, highlighting the importance of the teacher’s presence when
      the teaching modality was fully online (Fig. 3vii).
   2. The number of questions increased by 75% and 51% compared to the questions posted in
      2019 and 2020 respectively.
   3. The instructors responded to a higher percentage of the questions.
   4. The answers were provided faster, the median waiting time with fully online teaching
      was 56 minutes, whereas with on-site teaching the median time was calculated at 4.2
      hours.
These results help to dimension the work overload experienced by teachers and teaching
assistants since the beginning of the pandemic.
  Regarding the comments’ structure and usage analysis:
   1. The posts were longer and more complex than those posted in previous years.
   2. The contributions posted anonymously decreased with fully online teaching. Possible
      explanations include; the students’ want to be identified by their instructors and peers
      due to the lack of direct contact; as the students never met in person, neither the teacher
      nor their peers, they could feel less exposed participating in the forum.


5. Discussion and proposed analysis
This paper presents the initial conclusions of an exploratory analysis performed with three
years of discussion forum data. Previous research focusing on discussion forum interactions
and their evolution usually relies on a specific course or teaching modality. In contrast, this
paper combines the descriptive analysis of the networks’ structure with the posts’ features
to compare the impact of the teaching modality choice on the usage of the forum, and over
the participants’ interactions. This approach allowed us to notice that the teaching modality
impacted not only the activity levels, but also the way the students’ and instructors’ connected
with other participants, as well the comments features (e.g. length and anonymity status).
   Initial insights from the descriptive analysis of the temporal networks created and their
measures indicate that this approach is appropriate for researching the differences in the
interactions and usage over time between teaching modalities. However, one limitation of this
research is the learning context of the discussion forum in this study; which might prevent our
conclusions from being extended to courses with mandatory or graded forum participation.
   The subsequent work of this study includes the exploration of temporal network measures
for students and their differences across teaching modalities. Furthermore, the relationship
between the temporal network measures, their evolution, and the academic performance should
be explored in more detail to develop models that account for teaching modality and help to
identify students at risk of failing or drop out.
   Both the initial and final results obtained from this research will contribute to the LA field by
enhancing our understanding on the effect of teaching modality choices in higher education. In
addition, this research will help to advance in the still limited research on temporal networks in
educational contexts.


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