Location Privacy in Spatial Crowdsourcing

Spatial crowdsourcing (SC) is a new platform that engages individuals in collecting and analyzing environmental, social and other spatiotemporal information. With SC, requesters outsource their spatiotemporal tasks to a set of workers, who will perform the tasks by physically traveling to the tasks' locations. This chapter identifies privacy threats toward both workers and requesters during the two main phases of spatial crowdsourcing, tasking and reporting. Tasking is the process of identifying which tasks should be assigned to which workers. This process is handled by a spatial crowdsourcing server (SC-server). The latter phase is reporting, in which workers travel to the tasks' locations, complete the tasks and upload their reports to the SC-server. The challenge is to enable effective and efficient tasking as well as reporting in SC without disclosing the actual locations of workers (at least until they agree to perform a task) and the tasks themselves (at least to workers who are not assigned to those tasks). This chapter aims to provide an overview of the state-of-the-art in protecting users' location privacy in spatial crowdsourcing. We provide a comparative study of a diverse set of solutions in terms of task publishing modes (push vs. pull), problem focuses (tasking and reporting), threats (server, requester and worker), and underlying technical approaches (from pseudonymity, cloaking, and perturbation to exchange-based and encryption-based techniques). The strengths and drawbacks of the techniques are highlighted, leading to a discussion of open problems and future work

Approach for creating useful, gamified and social map applications utilising privacy-preserving crowdsourcing

The production and use of geographic information have become easier and more social. The interactivity of maps has fundamentally changed, not only because the touch-based interfaces are easier to use, but also because maps offer possibilities to interact with others. Map applications allow citizens to contribute but also share content to others. This contribution and sharing done by regular people is referred to as crowdsourcing. Map applications that utilise crowdsourcing face specific issues regarding the creation process, the usefulness and the crowdsourcing. These issues, however, have not been studied comprehensively and lack real world examples. This dissertation is the initial step to fill this gap by studying map applications that utilise crowdsourcing. These map applications are described using the design science research approach. Three issues relevant for the map application studied are: 1) the creation process, 2) utility requirements and usability heuristics, and 3) crowdsourcing approach. These issues are studied by using the design science research approach to produce theoretical and empirical knowledge of three map applications utilising crowdsourcing. The aim is to use this knowledge to form a design science research based approach suitable for creating map applications utilising crowdsourcing. The results regarding the creation process indicate that following a specific approach will help in creating crowdsourced map applications. This dissertation provides a customised design science research approach for creating crowdsourced map applications. Furthermore, prescriptive knowledge that provides real world examples crowdsourced map applications is provided. The results concerning the usefulness of map applications utilising crowdsourcing indicate that there are specific utility and usability requirements to be accounted for. This dissertation provides key utility requirements and usability heuristics for crowdsourced map applications. In general, a map interface for exploring and sharing content is needed. The map interface should be simple, citizens should be supported and interaction should be intuitive. The results concerning the crowdsourcing approach of map applications indicate that there is a need for specifying how citizens are involved in the process. This dissertation provides key requirements of the crowdsourcing approach of these types of map applications. The community driven crowdsourcing approach should be supported by official content and an engagement approach based on gamified and social elements to motivate content sharing. Privacy of citizens should be preserved by applying the privacy by design approach throughout the creation process. Privacy-preserving map applications utilising community-driven crowdsourcing, in which citizens can be engaged with gamification and social elements to explore and share content can be created by following the designs science research based approach presented in this dissertation.Geospatiaalisen eli paikkaan liittyvän tiedon tuotanto ja käyttö on helpottunut ja muuttunut yhä yhteisöllisemmäksi. Myös karttojen vuorovaikutteisuus on perustavanlaatuisesti muuttunut. Karttapohjaiset käyttöliittymät ovat yhä helppokäyttöisempiä ja niiden avulla kansalaiset voivat tuottaa tietoa, mutta myös jakaa sitä toisilleen. Tätä tavallisten kansalaisten tekemää tiedon tuottamista ja jakamista kutsutaan joukkoistamiseksi. Karttasovelluksiin, jotka hyödyntävät joukkoistettua tiedonkeruuta liittyy kuitenkin erityisiä haasteita niiden luomisen, hyödyllisyyden sekä joukkoistamisen osalta. Näitä haasteita ei ole vielä samanaikaisesti tutkittu kattavasti eikä näistä karttasovelluksista ole tarjolla tarpeeksi käytännön esimerkkejä ja tietoa. Tämä väitöskirja on ensimmäinen askel näiden haasteiden ratkaisemiseen, sillä tässä väitöskirjassa tutkitaan joukkoistamista hyödyntäviä karttasovelluksia. Väitöskirjassa perehdytään kolmeen karttasovelluksiin liittyvään haasteeseen, jotka ovat: 1) luomisprosessin lähestymistapa, 2) toiminnalliset vaatimukset ja käytettävyyden ohjeet ja 3) joukkoistamiseen käytetty lähestymistapa. Näitä haasteita tutkitaan tuottamalla tietoa kolmesta joukkoistamista hyödyntävästä karttasovelluksesta käyttäen kehitystutkimukseen perustuvaa tutkimusmenetelmää. Tätä tietoa käyttäen tavoitteena on muokata kehitystutkimukseen perustuvaa lähestymistapaa, jotta se soveltuisi joukkoistamista hyödyntävien karttasovellusten luomiseen. Luontiprosessin osalta tulokset osoittavat, että tieteellisen lähestymistavan seuraaminen helpottaa joukkoistettujen karttasovelluksien luomisessa. Väitöskirja ehdottaa muokattua kehitystytkimukseen perustuvaa lähestymistapaa joukkoistettujen karttasovellusten luomiseen. Lisäksi väitöskirja tarjoaa kuvailevia sekä ohjailevia tietoja joukkoistetuista karttasovelluksista käytännön esimerkein. Hyödyllisyyden osalta tulokset osoittavat, että joukkoistetuilla karttasovelluksilla on erityisiä toiminnallisia ja käytettävyyden vaatimuksia. Väitöskirja kokoaa keskeisiä toiminnallisia vaatimuksia sekä käytettävyyden ohjeita. Vaatimuksiin kuuluu helppokäyttöinen kansalaista tukeva karttakäyttöliittymä sisältöjen tutkimiseen sekä jakamiseen. Joukkoistamisen osalta tulokset osoittavat, että on tarve määritellä kuinka kansalaisen osallistuvat prosessiin. Tämä väitöskirja ehdottaa keskeisiä vaatimuksia lähestymistavalle joukkoistamiseen. Yhteisölähtöiseen joukkoistamiseen perustuvaa lähestymistapaa tulisi tukea karttasovelluksen sisällöillä, esimerkiksi kiinnostavalla taustakartalla. Lisäksi pelillisyyteen ja yhteisöllisyyteen perustuvalla sitouttamisella kansalaisia voidaan kannustaa sisältöjen jakamiseen. Kansalaisten yksityisyys tulisi turvata seuraamalla sisäänrakennetun tietosuojan lähestymistapaa läpi koko karttasovelluksen luomisprosessin ajan. Tässä väitöskirjassa esitettyä kehitystutkimukseen perustuvaa lähestymistapaa seuraamalla voidaan luoda yksityisyyden suojaavia ja yhteisölähtöistä joukkoistamista hyödyntäviä karttasovelluksia, joissa kansalaiset sitoutetaan pelillisyyden ja yhteisöllisyyden keinoin tutkimaan ja jakamaan sisältöjä

Framing the User Experience in Mobile Newsmaking with Smartphones

Mobile handheld devices are changing the practices of newsmaking, the roles of journalists and readers in it, and the published news in profound ways. The activity of mobile newsmaking aims at a tangible outcome, the news, which are consumed by an audience. Relatively little research exists in HCI (Human-Computer Interaction) that explores what is user experience of mobile systems in goal-oriented creative activity in organizational settings and especially in the natural contexts of use. This thesis addresses this gap by focusing on user experience, which arises when smartphones are used in mobile newsmaking to create and publish online and print news in the newspaper industry. This thesis has two main goals. First, it aims to gain a holistic understanding of user experience in mobile newsmaking with smartphones from the viewpoint of mobile reporters as users. Second, it explores how mobile and location-based assignments assigned by the newsroom can support cooperative newsmaking. This thesis contains nine scientific publications based on twelve case studies. The research approach of the studies is primarily qualitative. Seven of the studies included the usage of a mobile service client for newsmaking in the mobile context of use. Two of the twelve studies concentrated on reader participation in newsmaking as a form of mobile crowdsourcing. The rest of the studies focused on professional use. Over one hundred participants participated in the studies, of which a majority were students of visual journalism with prior work experience in journalism. The empirical findings are synthesized in the thesis summary. The model of user experience in mobile newsmaking with smartphones and the process model for mobile assignment-based processes summarize the thesis work on user experience and cooperative processes. User experience in mobile newsmaking is constructed in a process of using the mobile system in a goal-oriented and creative activity in the mobile context of use. The activity of mobile newsmaking consists of several subactivities starting from encountering a newsworthy event to the publishing of the news. It may include mobile reporter’s cooperation with others, who are in the field or in the newsroom. The constructed model of user experience has seven main components: user, system, the context of use, tangible outcome, descriptive attributes, overall evaluative judgments, and consequences. The model emphasizes the characteristics of the tangible outcome of system use (news material, news) as a fourth component that can contribute to user experience in addition to the characteristics of the user, system and the context of use. User’s experienced quality of the system is described by verbally expressible descriptive attributes divided to four components. The components of the descriptive attributes are the quality of the outcome (technical and content-based quality) and the perceived impacts (benefits and costs) that complement instrumental (pragmatic) and non-instrumental (hedonic) qualities from prior models of user experience. Ease-of-use, speed, light weight, small-size, unobtrusiveness, reliability, connectivity, controllability, being always along, and multifunctionality are key attributes for positive user experience. For users, pride of the outcome, fit with needs, motivations and goals, feeling of being in control, mastery of the system and activity, and the fit of the system to user’s role and situation are important. The process model for mobile assignment-based processes illustrates the coordination and cooperation related information and communication needs of the mobile reporter and the newsroom at differenct phases of newsmaking. The constructed models and synthesized results can aid academics and practitioners when designing, studying, and evaluating solutions for mobile work that can be complex, cooperative and creative and which aims at a perceivable or tangible outcome. They can also aid in recognizing the critical success factors of the solutions for different types of users and circumstances of the context of use. Further, results can aid when selecting and planning ICT solutions for media organizations and when planning the related editorial processes, workflows, and work roles. Finally, the constructed models can be used and validated in future research in other fields of mobile work and crowdsourcing

An exact single-agent task selection algorithm for the crowdsourced logistics

Agency for Science, Technology and Research (A*STAR); Fujitsu; National Research Foundation (NRF) Singapor