=Paper=
{{Paper
|id=Vol-1121/paper3
|storemode=property
|title=Semantic Web Technologies for Social Translucence and Privacy Mirrors on the Web
|pdfUrl=https://ceur-ws.org/Vol-1121/privon2013_paper3.pdf
|volume=Vol-1121
|dblpUrl=https://dblp.org/rec/conf/semweb/dAquinT13a
}}
==Semantic Web Technologies for Social Translucence and Privacy Mirrors on the Web
==
Semantic Web Technologies for Social
Translucence and Privacy Mirrors on the Web
Mathieu d’Aquin and Keerthi Thomas
Knowledge Media Institute, The Open University, Milton Keynes, UK
{mathieu.daquin, keerthi.thomas}@open.ac.uk
Abstract. While the open, collaborative and distributed nature of the
Web makes it an effective social platform, it also makes it difficult to
implement appropriate privacy management features. In this paper, we
discuss the notions of social translucence and privacy mirrors, originally
defined to be used as guiding principles for the design of (ubiquitous)
systems implementing some form of social processes, and how such prin-
ciples apply to privacy management for online interactions. The focus
of the paper is therefore on the technological challenges that are raised
in trying to implement these principles (visibility, awareness, account-
ability) in an open Web context. We show through several examples of
such implementations how the issues of data integration, data processing
and the need for inference that are raised by such approaches provide an
interesting use of semantic technologies, for individual monitoring and
sense-making of personal information on the Web.
1 Introduction
As argued for example in [20], privacy is a complex notion to define, depending
on the context and the purpose of providing a definition. [19] includes a survey
of the different views on privacy, alongside different perspectives. Besides the
very naive ones (e.g., “privacy is withdrawing information from other”), one of
the most natural definitions of privacy is the one described by [11] as “privacy is
not simply an absence of information about us in the minds of others, rather it
is the control we have over information about ourselves.” Similarly, Altman [2]
(as cited by [17]), defines privacy as “the selective control of access to the self”.
As some have shown [1], any control of personal information is determined
by the user’s perception of privacy - what information users regard as private,
from whom, and in what context, and depending on the privacy risks how the
users might make trade-offs. Thus, user’s control of personal information di-
rectly relates to feedback and awareness being necessary for privacy manage-
ment, and systems based on the exchange of personal information should be
“socially translucent system”, i.e., systems that “support coherent behavior by
making participants and their activities visible to one another” [10]. There is
no arguing that social, professional or commercial interactions on the Web rely
extensively on the exchange of private, personal information. However, on the
Web, the circulation of such information is happening in an un-restrained, frag-
mented and distributed environment. We therefore believe that one of the core,
and immensely difficult challenge for privacy is to enable the three principles of
social translucence–visibility, awareness and accountability [10]–with respect to
the open and unbounded exchange of personal information on the Web [6].
In this paper, we argue that, to tackle the technological aspects1 of such
a challenge–achieving social translucence for what concern Web-mediated com-
munications–Semantic Web technologies are not only useful but they are needed.
We show through preliminary models of systems related to what is described
in [18] as “privacy mirrors”, how the data integration, analytics and sense-
making capabilities that Semantic Web technologies can deliver in the complex
and distributed context of Web (personal) information can lead to increasing
individuals’ control over their own personal information, through raising their
awareness of the privacy implications of their actions on the Web.
2 Social Translucence and Privacy Mirrors
The notion of social translucence (as defined in [10]) is broader than its appli-
cation to privacy management. It concerns the design of systems with a social
process component, on aspects where coherent behaviours from the user(s) are
important. It is argued that, to achieve such coherent behaviours, it is necessary
for the system to make such behaviours visible and understandable to the users.
In other words, while it might not require to be fully transparent on every aspects
of its operations, the system should let the user see the relevant information for
them to make sense of their own activities, so to adequately tune their use of
the system, and of the social interactions it enables. [10] therefore characterises
translucent systems according to three main principles: visibility, awareness and
accountability.
There are obvious connections between the idea of social translucence and
privacy. As an objection to it, one might argue for example that social translu-
cent systems need to be designed carefully, so that visibility does not come to
contradict privacy. It is indeed the main argument for describing such systems
as translucent: they need to make enough information available to the user to
enable their informed use, but not to become so transparent as to enable unin-
tended use of the information made visible against the user.
A more constructive connection however between social translucent systems
and privacy is one where the principles of visibility, awareness and accountabil-
ity are used to enable a coherent and informed behaviour from the users with
respect to the distribution and propagation of their personal information. This
idea is especially well illustrated in “Privacy Mirrors”, a framework for designing
1
While we are aware that it is only a restricted view, and that other aspects related
for example to policies and the law are crucial, in this paper, we explicitly focus only
on the technological and tool-support aspects of Web privacy. The interested reader
might refer to [21], which makes the connection between the work presented here
and some non-technological considerations.
socio-technical (ubiquitous) systems so that they integrate the necessary tools
of “awareness and control to understand and shape the behaviour of the sys-
tem” [18]. It is based on five basic characteristics: history, feedback, awareness,
accountability and change.
Both social translucence and privacy mirrors have been defined in the context
of the design of systems implementing some form of social processes. However,
as already argued in [6], improving control and privacy management over on-
line interactions would require to achieve similar principles and characteristics
in a pre-existing, complex and open system (the Web) making it much more
challenging. Focusing on the first basic principles of privacy mirrors, providing
history, feedback and awareness on a user’s social activities on the Web raises
technological issues that are not present in closed, designed (even if ubiquitous)
systems: the need to collect information from various sources, to integrate it in a
coherent, manageable view, to analyse it and make sense of it in an open context
(i.e., not relying on domain and system specific assumptions), etc. These are the
challenges that we believe need to be tackled to achieve a more translucent ap-
proach to Web interactions, and where Semantic Web technologies can play a
major role in providing a more informed way of privacy management for Web
users.
In the next sections, we discuss some of these aspects through examples of
using Semantic Web technologies to improve the user’s visibility and awareness
of their own Web activities.
3 Data Integration for Web Interactions
Making information visible to users about their own activity in a system that im-
plements social processes first requires for the system to collect such information
in a way which is manipulable and transferable to the user. There are however
specific challenges that appear when trying to achieve this on online activity
data. Activity data typically sit in the logs of websites and Web applications,
and are exploited by online organisations, in an aggregated form, to provide
overviews of the interactions between the organisation’s online presence and its
users (most commonly in the form of website analytics). In [5] we looked at the
technological challenges that are faced when trying to invert this perspective
on activity data: provide individual users with an overview of their interactions
with the online organisation. Such challenges can be summarised as:
Fragmentation and heterogeneity: Activity data is typically held in log files
that have different formats, and might not be easily integratable from one
system (website, application) to another.
User identification: Recognising and identifying a user within the data is typ-
ically a problem faced by any activity data analysis. However, when taking
a user-centric perspective, a user needs to be identified over several systems
and the consequences of inaccurately recognising a user can be more critical.
Data analysis: Activity data is generally available through raw, uninterpreted
logs from which meaningful information is hard to obtain.
Scale: Tracking user activities through logs can generate immense amounts of
data. Typical systems cope with such scale through aggregating data based
on clusters of users. Here, we need to keep the whole set of data for each
individual user available to provide meaningful analysis of their interaction
with the organisation in a user-centric way.
In [5], we showed how we investigated and handled these challenges through
relying on semantic technologies, especially RDF for the low level integration and
management of data, ontologies for the aggregation of heterogeneous data and
their interpretation, and lightweight ontological reasoning to support customis-
able analysis of user-centric activity data. This involved in particular building
tools to:
1. Convert and integrate the data from their log format into RDF, following
the schema provided by given ontologies.
2. Create ontology level definitions of types of resources and activities to enrich
the initial data, to then apply ontology reasoning as a way to classify traces
of activities according to these ontological definitions.
3. Realise additional ad-hoc processing of the data, to improve interpretability.
This included in particular deriving the location of the user from their IP
(using a dedicated online API), deriving human readable labels for the user
agent (e.g., “Chrome 8”) from the complex user agent strings included in the
logs, deriving general date/time information from the timestamp included
in the logs (e.g. day of the week), etc.
As discussed in the next section, even within the limited scope of informa-
tion systems within one organisation, such semantic data integration of a user’s
interactions with online systems made it possible to create user-centric views
over such interactions, making such activities visible to them and leading to a
greater awareness of their own behaviour.
Taking a broader view on activity data, in [3] we experimented with the
user-centric collection, aggregation and processing of information regarding an
individual’s interaction with Web systems. As shown in Figure 1, the idea there
was to intercept all the Web traffic coming out of a user’s computer, and inte-
grate the relevant information into an RDF representation, based on a simple
generic ontology of Web interactions. A number of studies were made on the
basis of this tool, collecting large scale information for individual users (100 mil-
lion triples for a single user over 2.5 months). In [9], we showed how, based on
such data, we could reconstruct a complete user profile, aggregating and map-
ping personal information regarding dozens of attributes from the exchanges of
such information with thousands of websites. This demonstrated in particular
how the basic principles of Semantic Web technologies (linking and sense making
out of heterogeneous information) can support the construction of a user-centric
and user-interpretable view of an originally fragmented set of interactions and
exchanges.
Fig. 1. A local proxy system for collecting information about a user’s Web interactions.
A common objection to this approach (creating an aggregated view of per-
sonal data for the benefit of the user) is that it might itself create a privacy
threat. We qualify such an objection as naive, considering that it is merely
making available to the user a process that is otherwise in use by large online
organisations outside of the user’s reach and control. Of course, we do not mean
to say that it does not create additional risks. It is indeed crucial that such risks
are appropriately tackled through the secure, local storage and access to the col-
lected data in any implementation of the approach. However, since we focus here
on the role of semantic technologies, we see these aspects and their implications
on computing resource requirements outside the scope of the paper.
4 Personal Analytics: Data Analytics on Personal
Information
Of course, building a user-centric view over activity data is not sufficient to
make this information visible to the user, and to make the user aware of their
activities. However, an integrated view created through semantic technologies
allows one to provide access and visualisation mechanisms that can help the
user navigating and making sense of these data. The interesting aspects here is
that such data might include many different dimensions. Through the integrated
representation of the user’s Web activity data built using mechanisms such as
the ones described in the previous section, we can obtain representations that
adequately represent all these dimensions, and that interlink them.
For example, using the data collected through the local Web proxy in [3], a
number of simple displays can be shown to the user that summarise their own
activities, from the time of the day when they are most active to their com-
mon search keywords or the geographical location of the websites they interact
with. However, one can also exploit the interlinked nature of these dimensions
to investigate in more details some activities that might appear suspicious. For
example, one might notice from a map-based visualisation that they interacted
with websites located in Nigeria, and query the system to obtain more informa-
tion about the times of these interactions, or the type of information exchanged
with these websites.
Fig. 2. Personal analytics dashboard.
To show the benefits and possible use of such approaches, which we call
“personal analytics”, we described in [7] a study where we developed a personal
analytics dashboard using information from the logs of various systems in an or-
ganisation (The Open University), as described above and in [5]. The idea of this
study was to see what would be the uses and concerns members of this organisa-
tion might have when given meaningful access to a record of their own activities.
The dashboard, a view of which is visible in Figure 2, was built from querying a
triple store containing the integrated information about the activities of the user
on all considered systems, after this information had been processed to extract
interesting dimensions (time, location, type of activity). The interface was also
built to allow both usages of obtaining overviews of the activity (through charts
showing information about the overall user activity) and of querying the data
for specific information (by enabling the users to filter the displayed information
on all dimensions, based on values in one of them–e.g., clicking on the time chart
for “Sunday” to see only activities carried out on a Sunday). The study was then
conducted by interviewing participants at the time they were being confronted
to their own online activities through the dashboard. While the goal was not to
focus on the responses specifically related to privacy, we could certainly identify
different views, matching the common fundamentalist/pragmatist/unconcerned
divide [12]. More interestingly however, this study allowed us to identify possible
uses one might make of having a view over their own activity data:
Self reflection: Some participants of the study saw value in simply being able
to reflect on what they do, on their own usage of resources and especially on
how it reflected the way they worked.
Improving the use of resources: Very much related to the previous use case,
the most commonly mentioned potential purpose of having access to one’s
own activity data is to improve the use of online resources, and to make
it more efficient. This includes cases where the analysis of past activities
would lead to a change in behaviour with respect to interactions with online
resources.
Tracing anomalies: In a way somehow more specific than the one above, a
commonly mentioned use of activity data is to trace back and find evidence
or information related to some kind of anomalies in the users activities.
Participants mention scenarios such as being able to check that an activity
was properly carried out, or to analyse a situation that might have led to a
privacy related issue.
Ensuring transparency: This use case is somehow different from the three
others, as it does not really relate directly to the use of online resources or
even activity data, but generally to the relationship with the organisation
collecting these data. Indeed, while several participants did not see the col-
lection of activity data as being in anyway worrying, it is often mentioned
that it is simply “good to know what they know”.
While, out of the four usages mentioned here, not all explicitly relate to
privacy, they show that there is value in making activity data visible and un-
derstandable to users, and that even simple data integration and analytics tech-
niques can help achieving that. It appears clearly that, while only a preliminary
attempt, such personal analytics tools have the potential to make the Web a
more translucent system, increasing users’ awareness of their own activities and
their ability to shape their use of online systems appropriately.
5 Reasoning to infer hidden privacy connections
In the previous sections, we showed how semantic technologies can be useful
in creating the features of translucent systems for the Web, through data inte-
gration, manipulation and analytics. However, having access to data does not
necessarily imply being able to make sense of it. Here, we argue that an even
more critical aspect to a “Web privacy mirror” is that it should provide a way
for the user to compare what can be understood from their activities as observed
by the system to what they intended them to be. This requires the ability to in-
terpret information integrated in the way described above at a higher conceptual
level than what can be done with just the raw data.
This point was argued in [4] and described previously in this paper, where
data obtained from the local web proxy was used to confront the user so as
to measure their trust of online organisations and the sensitivity they attribute
to their own personal data. Information was first computed on the basis of the
raw data related to which online systems received which piece of personal infor-
mation (e.g., facebook.com received the user’s phone number). Based on this
information, two measures were calculated:
– The observed trust the user gave to an online system, based on the idea that
for a system to receive critical information implied that they were trusted.
– The observed criticality of a piece of personal data, based on the idea that if
a piece of data is shared with many untrusted online systems, it must have
low criticality.
These measures are dependent on each other and need to be calculated recur-
sively.
Calculating such measures had the objective of confronting the user, who
might have their own idea of their behaviour, with information about what can
be inferred from their actual, observed behaviour. This was achieved through an
interface showing the ranking of online systems based on trust (right of Figure 3)
and of pieces of personal information based on criticality (left of Figure 3). The
user then had the ability to move each element around, and dynamically see the
effect on the calculation of the two measures on other elements. For example, if
the user was to manually increase the criticality of a given piece of information,
they would see the websites that have received this piece of information move
up in the trust ranking.
Besides the complex technological implementation to achieve this result, the
interesting aspect of this system is that it represents an implementation of the
five characteristics of privacy mirrors applied to the environment of the open
Web: it provides history of the interactions between the user and online systems.
It uses this history to give feedback to the user regarding what can be inferred
or concluded from observing these interactions leading to a greater awareness
of the consequences of the user’s own behaviour. This in turn increases account-
ability by making it possible to trace the origin of certain inferences and it also
effects change by providing information on the user’s behaviour in relation to
the perceived or calculated privacy state.
Fig. 3. Observed measures of trust in websites (right) and criticality of pieces of per-
sonal information (left) for a given Web user.
6 Related work
As [12] has shown, users can be classified according to three main categories (un-
concerned, pragmatics, and fundamentalist) with respect to privacy. However,
such studies only consider what the users declare to be their behaviour online.
In [13], the authors show that, when looking at the actual behaviour of users
in concrete scenarios, there is little being done even by the most privacy and
technology aware of users i.e., the fundamentalists, which effectively supports
the protection of personal information online. Our hypothesis here, supported
by the notions of social translucence and privacy mirrors, is that this is partly
due to a lack of visibility and awareness of Web users of their own activities,
which is in turn partly due to the lack of appropriate technological support for
such awareness and visibility on the Web.
Indeed, the inherent complexity and fragmentation of the flow of personal
information on the Web makes it difficult for an individual Web user to monitor
and make sense of their own information without appropriate technological sup-
port. In contrast with such a complexity, some of tools currently available [15,
14] only provide coarse-grained control options, are not able to support the pro-
cess of assessing the implications of the potential aggregation of information
published in a distributed fashion, and do not consider the complexity and va-
riety of channels through which online activities happen. Typically, users would
simply use popular Web search engines to check websites where their name
appears [16]. Services such as Garlik2 have emerged recently, providing more
advanced approaches to monitor the Web for personal information. Other com-
mercial services such as Trackur3 and Visible Technologies4 are able to monitor
social media sites for references to a person.
Many discussions have taken place recently regarding the addition of a ‘do-
not-track’ option in Web browsers. However, to understand the extent and po-
tential impact of tracking mechanisms in relation to their own online behavior
requires appropriate information for Web users. Tools such as Gosthery5 have
appeared, which display to users the tracking mechanisms used on visited web-
sites, but without the ability to monitor the connections to such trackers across
time, or to link to relevant actions (e.g., the use of the do-not-track option,
or blocking the connection to the tracking service). Similarly, a number of ba-
sic tools have emerged recently that provide Web users with personal analytics
features, based for example on their Facebook activities6 or on their browser’s
history (using dedicated browser extensions).
2
http://garlik.com
3
http://www.trackur.com
4
http://www.visibletechnologies.com
5
http://www.ghostery.com/
6
see the personal analytics feature of Wolfram Alpha - http://www.wolframal-
pha.com/facebook/
7 Conclusion
In this paper, we discussed the notions of social translucence and of privacy
mirrors, and how achieving such approaches to privacy in an open Web context
requires technological advances that are typically found nowadays in Semantic
Web systems. We discussed these aspects by illustrating several systems we de-
veloped in the past and that implemented, at least partially, this idea of semantic
translucent Web interaction. Indeed, achieving social translucence on the Web,
especially to implement privacy mirrors, creates interesting technological chal-
lenges that fit the Semantic Web agenda. The ability to integrate, analyse, ma-
nipulate and reason over meaningful, processable data coming from distributed
heterogeneous systems is here required, and to make privacy management fea-
sible on the Web, will need to become part of the normal activities of everyday
Web users. While we focused here in some specific examples, we believe this to be
a general statement that needs to be considered in many different contexts. For
example, we are currently studying the privacy settings of online systems such
as Facebook, not from a purely technical point of view, but from the perspective
that they currently obscure, more than they make visible, the consequences of
using such systems on theirs users’ privacy state. We believe that, through the
appropriate semantic modeling of these mechanisms and through giving users
the possibility to employ such semantic model to build their own view of their
own activity, we can increase their ability to control the dissemination of their
personal information, and therefore their privacy.
However, the claim that Semantic Web technologies are needed does not
imply that they are sufficient. It appears clearly that privacy implications cannot
be purely represented through straightforward data modeling and be considered
only within an ontological reasoning framework. While some aspects do fit well
the ontological perspective promoted by the Semantic Web (e.g., in defining basic
implications on the inclusion of users in certain categories in Facebook), what
is required here are higher level inferences regarding the information these users
have access to, which could be achieved for example by integrating notions of
epistemic logic into the considered reasoning framework (see [8] for a description
of some preliminary work in this direction). Of course, another critical challenge
is that we are suggesting here to provide everyday web users with the ability
to employ complex and sophisticated Web, data management, semantic analysis
and reasoning technologies on their own data, collected from their own Web
activities, and for their own purpose. Critical work is required on the usability
and human-interaction aspects of Semantic Web technologies in order to make
such a vision feasible.
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