Foundations of Map-based Web Applications

A Survey of the Use, Limits and Opportunities Offered by Digital Maps

Alessio Antonini

, Guido Boella

, Stefania Buccoliero

, Lucia Lupi

and Claudio Schifanella

Dep. of Computer Science, University of Turin, Corso Svizzera 185, Turin, Italy

Interuniversity Department of Regional and Urban Studies and Planning,

Polytechnic of Turin and University of Turin, Turin, Italy

Keywords: Urban Informatics, Digital Maps, Web Applications, Data Visualisation, Urban Entities, Urban Computing.

Abstract: Traditional maps are one of the oldest way to express relevant information on a locality base, as synthetic

representations of reality. The traditional visualization theory of maps and the related principles used to

structure spatial information can inspire the modelling of new solutions in the field of information

management in web application. But, the fast and generalized spreading of digital maps, and the related

production of geo-localized social media is not followed by a deep integration of map in web applications,

preventing the effectiveness of digital maps in solving pressing issues like aggregation, retrieval,

recommendation and presentation of spatial media. Through the analysis of key concepts of maps, this

contribution addresses the foundations of map-based applications, discussing the limits of current approaches

and introducing new opportunities based on deep integration between maps and applications.

1 INTRODUCTION

Traditional maps are one of the oldest way to express

relevant information on a locality base (Shahaf,

2013), combining and defining different semantics

using visual signs (MacEachren, 1995), in order to

present a synthetic representation of reality at

different scales and organizing data in a structure

defined by the purpose of the map (Keates, 2014)

(Okada, 2014). The traditional visualization theory of

maps and the related principles used to structure

geographical information can inspire the modelling of

new recommender systems for online tools, based on

the integration between data structure and interaction

of applications and digital maps.

Nowadays, the fast and generalized spreading of

digital maps, and the related production of geo-

localized social media, is due to the intuitiveness of

maps in representing reality. Digital maps often

complement web applications, even thoes

applications not specifically related to geographical

purposes such as social networks, public platforms or

thematic portals. Digital maps provide a spatial

context, an alternative query system and a

visualisation tool to spatial media.

Nevertheless apart from web geographical

information systems (Web GIS), digital maps are not

“fully” integrated in web applications, in terms of

features, interaction and information management.

The decoupling of maps and applications generates

ambiguities and counter intuitive behaviuor in web

applications, leading to segregating digital maps to be

uneffective “add-ons”.

Maps are used as “canvas” to present spatial

media, and to help users in selecting an area of

intereset – a bounding box is a section of the canvas-

and therefore a subset of application entries. The main

use of digital maps is to let users interact with the

system to navigate a surface (a world map), changing

scale and area of interest, and visualizing at the same

time extra sources of information as points of

interests (POIs) or other geometrical features.

A light-weighted use of digital maps does not

require any understanding of maps as knowledge

theory, because limited to the visualization of spatial

features mostly collected automatically (implicitilly)

through mobile devices. Current web applications

including maps cannot be considered “map-based”

since not exploiting map features in the information

management: representation, retrieval,

recommendation and visualisation.

This contribution enquiryies how the theory about

of maps can be reflected in web applications, how a

map-based application should integrate maps

Antonini A., Boella G., Buccoliero S., Lupi L. and Schifanella C.

Foundations of Map-based Web Applications - A Survey of the Use, Limits and Opportunities Offered by Digital Maps.

DOI: 10.5220/0006136600920099

In Proceedings of the 12th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications (VISIGRAPP 2017), pages 92-99

ISBN: 978-989-758-229-5

extensivelly, which are the limits of common

approaches and new opportunities. Specifically, maps

are analysed from multiple perspectives: data

visualisation, filtering, aggregation and

recommendation:

 How to extend visualization mechanisms used

to create maps from data sets of geographical

features to “points of interest” (POIs)

 How to extend map scale theory to the

management of POIs

 How to use geographical entities in data

aggregation

 How to take in account users’ interaction with

a map in data collection

 How to build a geographical recommender

The theoretical concepts behind the definition of

maps are demonstrated to be relevant to provide a

meaningful and coherent context for spatial media.

The relevance theory within the implementation of

scales in cartography is presented as solution of the

issues about ambiguities of spatial feature of social

media and filtering, leading to the revision of the

current mataphor behind the interaction and

information management with digital maps.

The solution to the ambiguities in POIs collection

open the path to overcoming the current solutions in

data aggregation and filtering, defining suitable

alterntive to popularity ranking, and spatial

clustering. Moreover, the strong connection between

POIs and geographical entities a identification of the

connection between POIs and geographical entitie

open the possibility to new multiple solutions.

The rest of the paper will discuss the theoretical

and technical steps needed after a state of the art and

followed by a discussion of open issues, further

research topics and conclusions.

2 DIGITAL MAPS

In web applications, digital maps provide the

geographical context of spatial media: the

visualisation as POIs of their position (spatial feature)

on a cartography. Also, digital maps support

exploring POIs with dialogue popups - clicking on

markers – and interacting with the map viewer

changing viewer bounding box and scale to change

the retrieved data.

Digital maps can be used to entry geographical

features such as positions, in alternative to using

addresses or GPS. But, the decoupling between map

status and the data leads to ambiguous entries, hard to

process automatically and to present to users (Figure

1).

The integration of digital maps in web

applications opens issues related to the heterogeneity

of crowd-data and design tools able to support

unexperienced users without a common ground. The

web domain forces toward intuitive and pragmatic

tools that can be used by everyone without any

training or guidance, and at the same time archiving

an overall good quality of the result.

Following, we are going to analyse current uses,

limitation and constraints of digital maps, outlining

alternative solutions and new approaches.

2.1 Information Management Systems

Nowadays, the importance of user-generated contents

(UGC) is continuously arising in many fields, and

crowdsourced unstructured and/or incomplete

dynamic data with spatial attributes need to be

organized and analysed in order to leverage their

immense value.

Web-GIS (web geographical information

systems) are a class of applications focused on

working with geographical information, providing

tools to define geometries (paths, polygons, lines,

multi polygons, points). Web-GIS are often supported

by volunteering and crowd-based geography

movements, and used to build big datasets of

geographical information where there is a lack of

official sources. The major project in this regards is

OpenStreetMap (OSM). Web-GIS specific focus are

geographical data, thus they cannot be bended to

social media where the geographical aspects are

important but marginal and with they do not share the

same efforts in terms of correctness of entries,

methodology, features, required training, etc.

Social media such as Facebook and Twitter, make

use of spatial features as fundamental part of their

strategies to handle crowdsourced big data. A crucial

part of the success of those applications is their effort

on usability: intuitive interactions, smart defaults,

action feedbacks, personalised interfaces, etc. The

result is archived combining any means like user

profiling, reasoners and domain specific

recommenders. Geographical profiling is the natural

consequences of adding geographical features to

social media.

2.1.1 Limitations

The concept of scale remains implicit in digital maps

and in location based social media. In general, what

you see on a map the application is not aware of and

therefore is not what you get interacting with the

application. Without considering the scale, the

Foundations of Map-based Web Applications - A Survey of the Use, Limits and Opportunities Offered by Digital Maps

organization of information does not reflect the user

experience, mostly oriented to search for different

sets of information at a neighbourhood, urban scale or

territorial scale.

Scale is a broad concept investing technical

schemas, urban plans, public strategies programmes

and many other fields, and it is referred to the need of

visualising different cluster of data in different scales

for specific purposes. This concept translated in

digital maps leads to do not aggregate information

considering the geometrical proximity of POIs based

on their coordinates, but their relevance at each scale.

Another aspect to consider in current digital maps

is that the spatial features of social media are mostly

ambiguous and under specified. For instance, what is

the meaning of a media position? A user is visiting

something or it is just passing by? Is the posted

content related to where a user is or from somewhere

else? In case of complex environment like shopping

malls, where the user actually is? There is a huge

effort in disambiguating this information but a major

contribution can come directly on less ambiguous

interfaces enabling users to specify where and what

they are doing and the scale of reference. In Figure 1

for instance, the same input (position) may have

different meaning according to the view scale,

problem that does not rise using address as reference

system.

Figure 1: A position changes meaning at different scale: the

marker is referring to Campidoglio square (a) and to the city

of Rome (b).

Furthermore, a disconnection between the

visualization state of the map and the application

status heightens the ambiguity of scale in user

interactions with digital maps. In other words, the

change of scale associated to a change of zoom level

is limited to the cartographic base, but it does not

change the status of the application in terms of

retrieval and visualization mechanisms.

2.1.2 Alternatives

Which aspects of the concept of scale should be

considered for web applications? In general, it is

possible to consider three kind of scales: cartographic

scale, geographic scale, and operational scale. The

cartographic scale address the relationship between a

distance on a map and a distance on the ground. The

geographic scale reflects the geographical structure of

social interactions and size, level and relations define

it. Operational scale corresponds to the level at which

relevant processes operates and include the traces of

actions belonging to the same chain of activities

(Lam, 1992) (Smith, 1992) (Howitt, 1998).

OpenStreetMap (OSM) is currently the biggest open

geographical data source available, and OSM’s

definitions of spatial entities are mostly focused on

space functions and uses (Marston, 2000). Therefore,

applications features relying on geographical data

should consider what is available beforehand

(operational and geographical scales).

In digital maps:

 The size is controlled by users through zoom

controls 

 The level of focus - local, national, regional –

is bounded to what is considered relevant at

each scale, from buildings to the city level, and

usually is related to a bounding box, defined by

two points, the South-West North-East

extremes of the map window 

 OSM entities are rendered as geometries

according with their size and vertical ordering

 Names are rendered as labels over geometries

The connection between the state of the map and

the state of the application can be archived reflecting

the change of scale within the application. Changing

the zoom level changes the cartography but not the

data on the map. There is not an explicit mapping

between the zoom levels and scales which can be used

to create a dynamic visualisation system.

The status of a map is not limited to the bounding

box but also to geographical units currently visible,

ranging from administrative entities as for instance

cities or districts, to informal boundaries as

neighbourhoods, to spatial units as building blocks,

public spaces or buildings (Figure 2). The concept of

geographical unit is connected again to the scale, as

the scale change the relevant units change. This

mechanism unveils the existence of a “focus layer” of

entities which are significant - and highlighted in the

cartography at - changing as the map status changes.

Connecting POIs and geographical unites is therefore

possible to filter the information as the users interact

with the map, in a more comprehensive way.

Furthermore, key concepts of a map implemented

with the map theming, symbols and legends can be

extended to information management and vice versa.

A map legend can be effectively reflected in the data

organisation and for instance, a category system can

be used to generate map theming dynamically.

HUCAPP 2017 - International Conference on Human Computer Interaction Theory and Applications

(a) (b)

Figure 2: Example of geographical units considered for the

indexing system: building (a) and square section (b).

In digital maps, theming and scales are

implemented into styling rules defining what should

be rendered and how - colours, labels, hatches, lines,

symbols, vertical order - during the map generation

process. Following an example of styling rule about

how to fill the buildings polygons from CartoCSS in

Mapbox (https://github.com/mapbox/carto/):

[

class='street’][zoom>=9]{

line-pattern: @small;

[zoom>=13]{

line-pattern: @medium;

}

[zoom>=16]{

line-pattern: @big;

}

In this example, the CSS rules {…} are valid for

the interval between 9 and 22 (max zoom possible),

from the city to the indoor level. Following the

previous example, streets do not have a style for

levels higher than 9 and consequently not rendered

(even if the information is still there). The inner rules

override the styling of streets accordingly to the zoom

level. At 13 and 16 there is an increment of the size

of streets. For instance, the vertical ordering - a street

overlapping a river – is also encoded by styling rules.

Rules are applied to labelled spatial entities at

rendering time, but with current vector maps it is

possible to change them dynamically. The logic

within styling rules can effectively extracted and

generated, enabling a two-way connection between

cartography and application.

Summarising, as the map changes POIs can be

filtered, and as users exclude/include contents with

other tools the map theming can also change.

Moreover, the theming can be connected to

application organisation system such as categories

and vice versa.

2.2 Data Viewers

Technically speaking, digital maps are web viewers

for pyramid images (cartography). The cartographic

bases are images (raster, svg) or data sources

organised as “tiles” in layers. A tile is a bounding box

of fixed dimension, identified and retrieved by a

triple: z for the layer, and x and y for the area. A map

viewer is a tool to identify and retrieve tiles,

converting the bounding box and zoom level in triples

and to present tiles and layers of geographical

features on a spatial canvas. POIs are represented by

their geographical feature (point) in overlay layers

above the tile layer.

2.2.1 Limitations

One of the most common limit of digital maps is the

lack of control over the visualized information. The

visualisation of data is done pushing data in overlay

layers, which are implemented as arrays. The map

viewers usually provide control over the visualisation

of layers but not about the contents of layers beside

the bounding box. For instance, dynamic information

can make maps overcrowded and impossible to be

used, which is in contrast with the very purpose of

maps in general: synthetic representations based on

hierarchical representation of information and

selection.

Figure 3: Aggregation approaches: (left) marker clustering,

(centre) heat map, (right) grid-based aggregation.

The problem of overcrowded maps is addressed

directly by applications through filtering,

recommendations, and ranking (ordering solution) in

conjunction with specific solutions for digital maps,

like spatial clustering (Figure 3). Spatial clustering

creates dynamic clusters of markers accordingly to

their distance, ignoring geography of their location

like physical barriers and administrative boundaries

(Figure 4), and other distances like street routes.

Ordering solutions are used in combination with

limits on the results, e.g. top 100. The limit that can

be global (in a bounding box) or local to each section

of the map (tiles). It can be implemented hiding

marker or using marker of different dimensions.

Foundations of Map-based Web Applications - A Survey of the Use, Limits and Opportunities Offered by Digital Maps

Figure 4: Marker clusters take in account the distance (left)

despite any physical obstacles like a river (right).

2.2.2 Alternatives

Again, the limits of the mentioned approaches are due

to not considering maps as knowledge systems.

Considering data structures of maps, the projection of

a subset of geographical features should be done

coherently with a synthetic theory implemented in

theming and scales. In other word, the data

visualisation can be based on accordingly to the

hierarchy implemented in the current scale and on

what is currently visible in the cartography. To bridge

maps and applications views it is required to use the

same rules in generating maps within the application.

Alternative solutions to overcrowded maps can be

built on top of the visualisation of geographical

entities on maps, in terms of type like buildings,

administrative areas, parks. The connection between

POIs and geographical entities can be used to transfer

properties from geographical entities to POIs and vice

versa. For instance, the hierarchical organisation and

vertical alignment of geographical entities can be

reflected on data overlay layers in alternative to

highlighting popular contents.

2.3 Recommender Systems

Digital maps are currently used as location-based

filtering systems, instead recommendation is mostly

based on users’ spatial profile or their current

location. But current web technologies allow to

generate maps almost runtime, applying dynamic

themes and even manipulating map data sources. Can

dynamic maps support recommendation?

POIs recommendation is still a major issue in

location-based social networks. POIs have spatial and

temporal dimensions, making this domain hard for

common recommender (Griesner, 2015). The

recommendation of POIs should also be user-based,

location-aware, and context dependent (Liu, 2013).

There are several possible approaches to build a

geographical recommender system:

 to combine temporal and spatial dimension of

POIs (Griesner, 2015) (Lu, 2015) and to use

time/location data of users;

 to exploit POIs content, considering associated

textual and context information (Liu, 2013);

 to collect data about the interactions of users

with digital maps and update their profile with

category preferences and locations (Oku,

2010).

 to extend the friendship-based approach to

locations (Ye, 2010), considering the emerging

correlations between friendship and favourite

places.

2.3.1 Limitations

Users’ geographical profile is not always a reliable

source of information, in particular where users can

access the same platform for very different purposes,

like in case of public portals and civic platforms. The

users’ current goal is unknown and it cannot be

inferred especially in multi-thematic and

multipurpose platforms. For instance, the reasons

behind selecting a place, planning an activity,

enquiring for a service or trading a good is commonly

implicit and overlooked, and not reflected on map

views.

In this context, users have a passive role – without

control - in determining which contents are displayed,

and recommended contents based on users’

geographic profile is just the result of an aggregation

of preferences associated to spatial features.

2.3.2 Alternatives

Map theory again can support the definition of new

geographical recommender system, which do not

require users’ geographical profile, but can exploit

the geographical types in combination with users’

activities, giving control to users on what they want

to see case by case.

Traditional maps are “a priory” recommender

systems, where readers could see only a specific set

of information, accordingly to what they need,

selecting the right kind of map, in terms of scope,

scale, purpose/theming.

Currently, digital maps open a wide range of

approaches, providing the possibility to create

multiple maps from the same data source in term of

theming and scales. For instance, it is possible to

settle a general goal “traveling” and different

approach at each scale “walk”, “bike & car”, “bus &

train”, “airplane & boat”, generating very different

vires.

The introduction of an indexing system for POIs,

using geographical units connected to the zooming

system results in: 1) providing a tool to users to

explicitly control the results and 2) extending the

recommendation aspect from maps to geographical

units and then to contents.

HUCAPP 2017 - International Conference on Human Computer Interaction Theory and Applications

Interactivity is the main features of digital maps,

enhancing the value of users’ inputs on maps enhance

the effectiveness of the map as tool without raising

the overall complexity of a web application.

Users’ needs play a central role to understand

what connects their favourite locations and their

activities (Guy, 2015). In this perspective, we propose

to start considering users’ actions, in alternative to

systems based on users’ spatial profiles. Allowing

users to control the outcomes and introducing a

concept of users’ contingent goal/task consent to

provide a tailored support to their current activities. A

goal is something that can be handled by users

directly and explicitly reducing the premises to how

best support specific user activities rather than

guessing users’ interests.

As result, maps can be shaped dynamically

accordingly to users’ tasks, for instance removing

useless entities and highlighting a work area like a

district or neighbourhood.

3 MAP-BASED APPLICATIONS

What are the features of a map-based application? An

application can be considered map-based if it exploits

the core mechanisms of maps in such a way that

interacting with a map is interacting with the

applications’ entries and as the map status changes

the application status changes and vice versa. Thus,

the fully integration between map and application is a

requisite to provide an intuitive tool, improving the

overall capability to manage complex scenarios such

as social networks, or any big data, relying on the

geographical features of data.

A map-based application should implement the

principle “what you see is what you get”

(WYSIWYG), solving the ambiguity of data input,

and the decoupling between map view and

application data. In this regards, not all web

applications using maps should be map-based. For

instance, hotel web applications do not need to

provide any other information aside hotels, therefore

there is no need to consider scales or implementing

dynamic theming.

Summarizing, a map-based application should

support the following mechanisms:

 The connection between application contents

and map entities, that each spatial media is

linked to a geographical entity;

 The connection between map status and

application status, or rather actions in the

application should be aware of the current

status of the map in term of scale, area and

available entities for users.

3.1 Information Management

What does it mean to connect map and contents? As

general principle, connecting a map to its content

means to show, hide and highlight accordingly to the

map goal. For instance, a political atlas shows nations

despite their size, population or political influence,

and nations are usually coloured to highlights their

boundaries, but there are no orographic references or

any other element describing their morphology. A

political atlas is not meant to describe orography nor

morphology of countries, but to show the physical

relations among them. Conversely, in physical atlas

countries with similar territory can be easily confused

– there is not a neat distinction of national borders -

because the aim of this kind of representation is to

highlight natural element characterizing the territory.

Maps produced for different goals contain and show

different elements.

Considering another perspective, road guides are

books for traveling by car, usually organized in local

and national tables. National tables show main roads

such as highways and main dorsal railways. Local

tables contained also secondary and local streets.

Even if local and national tables are intended to show

similar entities (streets, railways, paths) and they

looked very similar, their content is different. Even in

this case, maps select information for the user,

considering different goals: travel by car to reach a

place or to explore and find a specific address of a

place. The representation theory about scales is

directly linked to theories of relevance about map

contents.

Digital maps allow users to change the map zoom

to observe different portions of space, but this kind of

interaction does not necessarily affect the map scale.

In fact, there is not an explicitly connection between

zooming and scale because scales are usually outside

the scope of applications, encoded in “tile servers”

(map providers). Even if a map switches from a zoom

level to another does not mean that map contents

change accordingly, this leads to overcrowded maps.

Making explicit the connection between map and

content management will reproduce the same use of

physical maps, the choice of the right map for the

current use but seamlessly. This requires to build a

data structure based on the data source of maps,

which can be possible only with crowd-based and

volunteering geographical data sources.

Foundations of Map-based Web Applications - A Survey of the Use, Limits and Opportunities Offered by Digital Maps

3.2 Connecting Maps with Applications

Why are POIs cannot be connected to geographical

entities in current applications? Digital maps are

considered “flat” even those they are not. The data

layers and POIs are “pinpointed” on maps, without

any regard to what lies behind. The current metaphor

is using maps as pincushions, without any connection

between map and markers (pinpoints).

Pinpointing a marker on a map is maybe the

easiest method to add the spatial dimension to

contents, and the practice demonstrates that so far is

a solid metaphor when comes data collection. In fact,

very few non-geographic systems support anything

more than markers.

But in terms of other tasks we may find a more

suitable metaphor considering again the data structure

behind maps and how users interact with them. Rather

than pinpointing the action of placing POIs is

“dropping” them on geographical entities. What is the

difference between pinpointing and dropping? Even

if technically raster maps are flat, we can assume

users placing POIs considering a structure of ordered

elements they saw: streets are above rivers, buildings

are above parks, etc.

Spatial entities work as castle of “buckets” one

inside another, in respect to their size and vertical

ordering. POIs are falls inside these buckets because

users can “see” where they place them. Applications

not aware of what users are interacting with are

disregarding partially the meaning of users’ actions

with the consequence of losing the essential

information and failing in representing correctly

users’ contributions.

Considering what users interact with saves a lot

of issues and computation, and it enables to build a

reliable connection among users’ contents and

geographical data by design.

3.3 Applicative Solutions

The requisite is the connection between POIs and

geographical entities instance. It can be archived

introducing a specific geographical index recording

the relations as users generate contents (Antonini,

2017). The indexing system requires the definition of

focus layers, a coverage made of geographical units,

for each defined level of the index.

As users change scale the application can load the

relative focus layer, to build features based on the

understanding of what users can see and can interact

with. It enables to:

 Dynamically change the map theming

 Filter POIs which are not related to the

geographical unites in the current focus layer

 Enhance the entry of data on maps, from points

to “deep” points referring to a specific scale

 Aggregating information accordingly to the

geographical entities they belong to (Figure 5)

 Rank POIs accordingly to the focus layer

The WYSIWYG principles can be archived. For

instance, a POI about a building is retrieved if the

building is retrieved, not only in terms of bounding

box but in terms scale.

Figure 5: POIs connected to geographical units can be used

to generate area-based aggregates, preserving the coherence

with the geographical data as users see them on the map.

The system provides support to synthetic

representations, saving computational costs and

relative approximations. It can have great impact on

performances, readability and intuitiveness, even

with critical issues in web applications related to

crowd sourced big data.

In terms of recommendation, it is possible to

exploit the “type: of geographical entities to build

users’ “focus area” within the bounding box.

In Figure 6 the results of a first experiment. Using

a simple flooding algorithm, the users’ position is

expanded on a weighted visibility graph connecting

the visible geographical units. At users is given the

control of a “task” selector, where to express their

current activity. Tasks correspond to weights array

indicating the cost of expanding the area accordingly

to the “relevance” of the type of geographical units.

For instance, during “sport” crossing a street “costs”

much more than traversing a long park. The

expansion of the focus area was bounded to two

criteria, a maximum size of 50% of the bounding box

or the inclusion of 50% of POIs within the focus area.

In Figure 6 the shape outline of three areas

generated for the three tasks, starting from the same

dataset of geographical entities and POIs.

Figure 6: The outline of three focus area corresponding to:

(left) shopping, (center) education and (right) sport,

generated from the same setup: user position, POIs and

geographical data.

HUCAPP 2017 - International Conference on Human Computer Interaction Theory and Applications

The use of focus area to select geographical

entities and therefore POIs, is an alternative solution

to other recommenders not requiring user profiling.

4 CONCLUSIONS

This contribution addressed how the theory about

maps can be applied to web applications to archive

deep connection between data and interactions from

maps to applications and vice versa.

The revision of current approaches and their

limits were presented to introduce new opportunities

offered by the foundation of maps from multiple

perspectives: information management, data

visualisation, data filtering and recommendation.

It was addressed the issue of connecting

application data and geographical entities, discussing

a geographical indexing system able to provide to

applications the insight about what users “see”

interacting with a map. Based on the geographical

index, it was introduced the concept of focus layer a

coverage of geographical units relevant within a

given scale. Combining the connection between POIs

and geographical entities in focus layers it was

introduced the solution of area-based aggregation to

overcome the limitation of current clustering-based

approaches. Finally, it was presented the preliminary

result of a geographical recommender, which select

contents accordingly to users’ “focus area”.

Currently the presented ideas are being developed

in solutions to support civic platforms such as

FirstLife (http://firstlife.org/) and WeGovNow

(http://wegovnow.org/). The necessity to address

challenges issues such as aggregation, quality of

crowdsourced data, spatial filtering in a public

platform without relying on user profiling, was the

stimulus to pursue alternative solutions to main

stream approaches of social networks and thematic

web portals.

ACKNOWLEDGMENTS

A part of the research leading to these results has

received funding from the European Union’s Horizon

2020 research and innovation programme under grant

agreement n° 693514 ("WeGovNow"). The article

reflects only the authors' view and the European

Commission is not responsible for any use that may

be made of the information it contains.

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