=Paper=
{{Paper
|id=Vol-1153/Paper_7
|storemode=property
|title=A Reward Design Pattern in BCSS
|pdfUrl=https://ceur-ws.org/Vol-1153/Paper_7.pdf
|volume=Vol-1153
|dblpUrl=https://dblp.org/rec/conf/persuasive/AlahaivalaOO14
}}
==A Reward Design Pattern in BCSS==
https://ceur-ws.org/Vol-1153/Paper_7.pdf
Second
International
Workshop
on
Behavior
Change
Support
Systems
(BCSS
2014)
69
A Reward Design Pattern in BCSS
Tuomas Alahäivälä, Michael Oduor and Harri Oinas-Kukkonen
1
University of Oulu, Department of Information Processing Science
P.O BOX 3000 FI-90014 Oulu, Finland
{tuomas.alahaivala,michael.oduor,harri.oinas-kukkonen}@oulu.fi
Abstract. Although constructs have been developed for designing the features
of Behavior Change Support Systems (BCSSs), detailed descriptions and gui-
delines for their software level implementation are lacking. Through develo-
ping software design patterns one is able to examine BCSSs at a more intricate
technical level instead of merely a black-box approach to them. In this paper,
we present a software design pattern for rewarding users as a way of enhan-
cing persuasive human-computer dialogue in BCSS. The resulting pattern
contributes to both research on software design of persuasive system features,
and for assisting the practical development of such systems.
Keywords: behavior change supports systems, persuasive technology, persu-
asive systems design, human-computer dialogue, software design patterns
1 Introduction
Behavior change support systems (BCSSs) have been defined as information
systems that form, alter, or reinforce attitudes, behaviors, or acts of complying
without using deception or coercion [1]. They can provide solutions for problem
areas such as improving health and sustainability. The research into BCSSs fo-
cuses on the approaches, methodologies, processes, and tools for their design, as
well as their potential effects [1]. There are many features that add to the persua-
siveness of a system, such as those contributing to support user’s primary task,
human-computer dialogue, system credibility or social influence [2]. In this paper
we focus on conceptualizing a software design pattern for specifically implement-
ing rewards as a feature of persuasive human-computer dialogue in BCSSs. Our
study uses the design science research methodology, which includes an iterative
process of designing and evaluating a functional IT artifact to produce a solution
to the research problem [3].
Although a prominent research area, BCSSs have in prior studies been de-
scribed at an undetailed technical level [cf. 4–5]. The persuasion context, contain-
ing the case-by-case use, user, and technology contexts should be fully regarded
when describing a BCSS [2]. Describing systems without knowledge of its inter-
nals, or so-called “black-box approach”, makes it difficult to argue generalizable
results related to systems design [1]. By utilizing more software engineering ori-
ented approaches and tools such as software architectures and software design
patterns, BCSS research can be enhanced from proof-of-concepts to concrete
software development guidelines. There has been prior research on design pat-
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terns for persuasive systems, such as discovering persuasive patterns in social
networks and introducing a set of general patterns for influencing user behavior
through design [cf. 6–7]. While covering many aspects of persuasive design is-
sues, these patterns have been mostly presented at a generally high conceptual
level. We are aiming to reach a more detailed technical view into persuasive sys-
tems design by inspecting our patterns also from the object-oriented modeling
and code implementation level. This will also make our results presentable to
both researchers studying persuasive systems design and practitioners implement-
ing future BCSSs. In this paper we will, based on the background literature on
Persuasive Systems Design and software design patterns, present a Reward de-
sign pattern for BCSSs.
2 Background
2.1 Rewards in Persuasive Systems Design
Oinas-Kukkonen and Harjumaa’s Persuasive Systems Design (PSD) model states
that the development of persuasive systems (including BCSSs) requires three
steps: understanding the key design issues related to persuasive systems, analyz-
ing the persuasion context, and designing the system qualities [2]. For under-
standing persuasion in a system, its use, user, and technology contexts should be
recognized. The use context covers the characteristics of the problem domain in
question, the user context includes the differences between the individuals, and
the technology context contains the technical specifications of a system [2]. A
lack of precision in describing the technological context has been common in
prior studies on BCSSs, making it difficult to understand the persuasiveness of
these systems as a whole [1].
Concerning the design of the software features of persuasive systems, Oinas-
Kukkonen and Harjumaa have proposed four categories of design principles:
primary task, dialogue, system credibility, and social support [2]. These design
principles may function as guidelines for determining software requirements, as
well as an evaluation method for persuasive systems. The dialogue support cate-
gory contains design principles for system features that concern the dialogue
between a system and its users. These features include praise, rewards, reminders,
suggestion, similarity, liking and social role. By providing virtual rewards a sys-
tem works as a motivational tool [2]. In this paper we will focus on the rewards
feature of persuasive systems.
2.2 Software Design Patterns
Patterns are reusable solutions that can be applied to commonly occurring prob-
lems in software design and enable building of systems with good object-oriented
design qualities [8]. They do not provide the code, but rather provide solutions to
general design problems, which are to be applied to specific applications – a solu-
tion to a problem in context. They serve as templates that can be used in different
ways for solving problems. Most patterns allow some part of a system to vary
independently of all other parts and these varying parts are often encapsulated.
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Use of patterns provides a shared language that maximizes the value of commu-
nication amongst developers and reduces the time spent on making design deci-
sions related to feature changes and enables reuse of solutions that have previous-
ly been effective. Furthermore, they aid in avoiding design alternatives that com-
promise reusability and they can improve documentation and maintenance of
existing systems by providing an explicit specification of class and object interac-
tions and their underlying intent [8–9].
Patterns depict the static and dynamic structures and collaborations of suc-
cessful solutions to problems–discerning of non-functional features for example–
that arise when developing applications within a particular context. Patterns (or
their solutions) should be applicable in many different situations without the need
to make extensive changes as they provide ways to arrange and categorize rela-
tively mundane solutions in technology-related development projects. According
to Gamma et al. [8], patterns have four essential characteristics:
1. The pattern name – a common term that eases the communication
amongst stakeholders and enables design at a higher abstraction level
while simplifying thoughts on designs and communicating these and
their trade-off to others.
2. The problem describes when a pattern should be applied and its context.
3. The solution provides an abstract description of a design problem and
how a general arrangement of elements (classes and objects) solves it.
4. The consequences are the results and tradeoffs of applying the pattern
According to Buschmann et al. [10], there currently is a common set of well-
known generic software patterns but when looking toward future developments,
patterns could be more domain-specific and tailored to particular focus areas.
Many domain areas such as behavior change support systems are yet to be
properly covered by the pattern languages.
3 Reward Design Pattern for BCSSs
Rewards and virtual achievements are powerful motivational tools. A reward
system can make the process more enjoyable and help users get pleasure from
their tasks [cf. 11–12]. Rewards have an effect on intrinsic motivation, although
depending on the way they are delivered [13]. We now present a design pattern
for implementing reward features in behavior change support systems. For issu-
ing virtual rewards in a web-based BCSS, the performance of its users must be
monitored. This can be efficiently done utilizing the well-known object-oriented
Observer design pattern [8], which defines and maintains a one-to-many depend-
ency between objects such that a change in one object leads to all its dependents
being notified and being updated automatically.
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Building on Model-View-Controller (MVC) [14] and Representational state
transfer (REST) [15] approaches, we presume that the application’s resources are
implemented as their corresponding Models, Views, and Controllers with Create,
Read, Update, and Delete (CRUD) actions. There are at least two generalizable
resource entities that are necessary for a BCSS: the User resource and the Entry
resource. The User resource depicts the users of the systems, containing their
account information and possible behavioral profiles. The Entry resource is an
abstraction of the data that the user submits to the system to monitor her behav-
ioral habits – for example weight measures in a weight monitoring application, or
individual exercise activities in exercise a tracking application.
Hence, for providing the rewards functionality in BCSS, User, Entry, EntryOb-
server, Reward, and Accomplishment components are needed as seen in the class
diagram (see Figure 1). In the diagram, theUser model contains the profile infor-
mation of a certain user, User has a one-to-many relationship to the Entry–being
an actualization of a pursued behavioral habit–model: an Entry depicts an action
that the user submits to the system,, The Reward model contains the description
of the reward in question. The Accomplishment model depicts the many-to-many
relationship between the User and the Reward and is used for maintaining the
record of the rewards users have gained. The EntryObserver class then contains
the logic that observes upon creation of Entries, if they account for a reward and
if so, creates the corresponding Accomplishment. See Table 1 for summarization.
Table 1. Reward pattern
Pattern name Reward
Problem The system should give virtual rewards to users to further moti-
vate them to stay involved.
Components User, Entry, EntryObserver, Reward, Accomplishment
Solution The resources in the system should be modeled to implement the
User, Entry, EntryObserver, Reward and Accomplishment com-
ponents. When the User submits an Entry to the system, the En-
tryObserver component observers whether the action is eligible
for issuing a reward to the user.
Consequences Rewarding users for performing after their target behavior moti-
vates them and assists their goal setting. But it should be minded
that all users might not find rewards as desirable.
Second
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Figure 1. Class diagram of the Reward pattern
4 Conclusion and discussion
In this study we have proposed the Reward software design pattern to facilitate
enhanced computer-human dialogue in behavior change support systems, based
on the PSD model. The paper’s implications for research are in providing an in-
tricate implementation level view of the software development aspects of BCSSs.
We hope that the object-oriented design and code level findings presented will
result in breaking out from the black-box thinking approach in persuasive systems
design, allowing researchers to inspect the internals of software components
needed to produce persuasive applications. In the future, a full set of design pat-
terns for BCSSs could be accomplished. Practitioner-wise, using the pattern will
assist in creating conventions to bootstrap future BCSSs development. The pat-
tern can be used to add rewarding features to existing behavior change support
systems, thus potentially increasing their persuasiveness. This study is limited by
the fact that the verification of the implied pattern was conducted only as describ-
ing the development of a demonstrative system prototype. For further proof, more
complex applications, which apply the pattern, should be developed. The applica-
tion of the pattern in different programming environments, languages, and
frameworks should also be studied. For example, whether the pattern applies in
the development of a native mobile application as well as of a web-based BCSS
could be studied. The presented pattern solely concerns the rewarding features in
a system, and there still remain many other persuasive system features that should
be covered when studying persuasive software design patterns. Thus, the future
work will include further definition and verification of the presented pattern and
developing new ones focusing on both human-computer dialogue and the other
aspects of persuasive systems design, such as social influence.
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Acknowledgements. This research is part of OASIS research group of Martti
Ahtisaari Institute, University of Oulu.
References
1. Oinas-Kukkonen H. (2013). A foundation for the study of behavior
change support systems. Personal and ubiquitous computing, Vol. 17,
No. 6, August 2013, pp. 1223-1235.
2. Oinas-Kukkonen, H., Harjumaa, M. (2009). Persuasive systems design:
Key issues,process model, and system features. In: Communications of
the Association forInformation Systems, 1, vol. 24, pp. 485-500.
3. Hevner, A. R., March, S. T., Park, J., & Ram, S. (2004). Design science
in information systems research. MIS Quarterly: Management Informa-
tion Systems, 28(1), 75-105.
4. Bennett, G.G., Glasgow, R.E. (2009). The Delivery of Public Health In-
terventions Via the Internet: Actualizing their Potential. Annual Review
of Public Health, vol. 30, 273–292.
5. Lehto T., Oinas-Kukkonen H. (2011). Persuasive Features in Web-Based
Alcohol and Smoking Interventions: A Systematic Review of the Litera-
ture. In: Journal of Medical Internet Research, 3, vol. 13, e46.
6. Weiksner, G., Fogg, B., Liu, X. (2008). Six patterns for persuasion in
online social networks. Persuasive Technology.
7. Lockton, D., Harrison, D., & Stanton, N. (2010). The Design with Intent
Method: a design tool for influencing user behaviour. Applied er-
gonomics, 41(3), 382–92. doi:10.1016/j.apergo.2009.09.001
8. Gamma, E., Helm, R., Johnson, R., and Vlissides, J. (1995). Design Pat-
terns: Elements of Reusable Object Oriented Software. Addison-Wesley.
9. Zhu, Z. (2009). Study and application of patterns in software reuse.
Control, Automation and Systems Engineering, 2009. CASE 2009. IITA
International Conference on, 550-553.
10. Buschmann, F., Henney, K., & Schmidt, D. C. (2007). Past, present, and
future trends in software patterns. Software, IEEE, 24(4), 31-37.
11. Ritterband, L., Thorndike, F., Cox, D., Kovatchev, B., & Gonder-
Frederick, L. (2009). A behavior change model for internet interven-
tions. Annals of Behavioral Medicine, 38(1), 18-27. doi:10.1007/s12160-
009-9133-4
12. Sohn, M., & Lee, J. (2007). UP health: Ubiquitously persuasive health
promotion with an instant messaging system. CHI '07 Extended Abst-
racts on Human Factors in Computing Systems, San Jose, CA, USA.
2663-2668.
Second
International
Workshop
on
Behavior
Change
Support
Systems
(BCSS
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75
13. Deci, E. L. (1971). Effects of externally mediated rewards on intrinsic
motivation. Journal of Personality and Social Psychology, 18(1), 105-
115.
14. Krasner, G., Pope, S. (1988) A Description of the {Model-View-
Controller} User Interface Paradigm in the Smalltalk-80 System. In:
Journal of Object Oriented Programming, 3, vol. 1, pp. 26-49.
15. Fielding, R.T., Taylor, R.N. (2002) Principled design of the modern
Web architecture. In: ACM Transactions on Internet Technology, 2, vol.
2, pp. 115-150.