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METHODOLOGICAL APPROACH FOR MOBILESTUDIES: EMPIRICAL RESEARCH CONSIDERATIONS

Silvia Elaluf-Calderwood, Jan Kietzmann and Amarolinda Zanela SaccolDepartment of Information Systems - London School of Economics andPolitical Science. Email: {s.m.elaluf-calderwood, j.h.kietzmann}@lse.ac.ukUniversidade do Vale do Rio dos Sinos and Universidade de Sao Paulo.Email: aczanela@unisinos.br

Abstract: Studies about mobility and mobile interaction help researchers and practitioners in the socialsciences to make sense of emergent working and living practices in an increasingly mobilised world.This paper aims to present a reflective analysis of the recommended methodological approaches formobile studies based on three case studies. Following mobile workers across the different dimensionsof time and space is a major challenge researchers have to face. The paper discusses thesechallenges, and highlights areas of interest for researchers interested in the study of mobility and mobileinteraction.

Keywords : Mobility, mobile technology, case study research, qualitative research methods,ethnomethodology.

1. Methodological approach adopted in mobile studies

Mobile studies have reflected the emergent working practices in ourincreasingly mobilise world (Urry 2000; Sorensen, 2002). In this context,researchers have pursued new proposals for the study of mobility and mobileinteraction by conducting various forms of fieldwork (Weilenmann, 2003;Laurier 2002). For this paper three case studies are discussed. Theirrespective contexts include the use of smart phones (a mix of a PDA and amobile phone) by Account Managers in the banking sector, mobile workersemploying SMS technology and highly mobile taxi drivers and their use ofmobile phones for work.

The underlying assumptions of these mobile case studies are focused onwork-related mobility within the parameters of office-work and fieldwork. Bymoving away from static work environments, researchers encounteredmethodological difficulties associated with collecting data within highly mobilecontexts. The obstacles identified include following the mobile device,following the user and following the mobile space, as well as theinterrelatedness of these factors.

Following mobile workers across the different dimensions of time and spaceare major challenge mobile researchers have to face. Following the data andfollowing a device is nearly impossible in some mobile circumstances, whichcan largely limit the insights and value of fieldwork research.

The paper discusses these challenges, and highlights areas of interest forthose willing to study mobility and mobile interaction. We aim to provide someinsights into methodological considerations that can be anticipated and mustbe acknowledged accordingly.

1.1 The case study consideration

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The three case studies adopt as main research paradigm an Interpretivistapproach. Interpretative methods of research start from the approach that ourknowledge of reality, including the realm of human action, is a socialconstruction (Walsham, 1993; Bijker, 1993).

The Interpretative approach tries to understand the world as it is, created byinter-subjective meanings in a social process. It tries to understand a socialphenomenon from the perspective of participants in its natural setting. In anInterpretative study, the researcher does not try to impose his/her ownprevious understanding onto the situation.

The three case studies presented in this article place a significantinterpretative value on the narrative as expressed by the object of study (bywhom is being interviewed and what is said in the context of study). Theunderstanding of the differences between the living situation of the mobileuser and the researcher’s hypothetical views is of paramount importance.Distinguishing between situated interaction in the world on one hand andinteraction thought technologies on the other is at the heart of virtualenvironments and mobility studies (Luff and Heath, 1998).

In the setting of mobile fieldwork settings, one method that can be usedsuccessfully to represent this interaction data is ethnomethodolody (Garfinkel,1986). Recent researchers have been able to withdraw meaningful data usingthis methodology (Laurier, 2002; Weilenmman, 2003). Ethnomethodologyassigns a contextual value to the details in the dialogues and narratives usedby ordinary people in their everyday activities when making sense of the worldaround them. This is exactly what we aim to reproduce from our observationsof mobile workers and their use of mobile technology.

The three research experiences presented in the sequence have adopted theCase Study Method (Gomm, Hammersley and Foster, 2000). Benbasat(Benbasat, Goldstein and Mead, 1987) indicate this method as proper whenthe current theory about a subject is at an initial stage, when the actors’experiences and views, as well as the context of action, are essential tounderstanding a social phenomenon. Therefore, case studies methods arevery useful for studying mobility and mobile interaction, considering that theseare emergent subjects in the Information Systems research field.

In this paper one study relates to a single case study (within a Brazilian bank);the other two are reflections of numerous cases (SMS technology, spatiallymobile workers). In all cases we have to pay attention to the field workpreparation associated with collecting data within highly mobile contexts,which rely heavily on the use of mobile technology for work allocation andexecution. Highly mobile contexts are defined for this purpose as workingenvironments where work is spatially distributed outside the traditional officespace (Hill and Ferris, 2003).

Considering this reference to study mobility and mobile interaction, wepresent in the sequence the three empirical research experiences, each one

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of them focusing on these three different approaches: following the contextualspace, following the actor and following the technology or the virtual space.

2. The study cases

2.1 Case study 1 - Following the contextual space: The spatial and timecontext of work

This first case sources its data from spatially mobile workers. A spatiallymobile worker is one who executes his work when travelling between twolocations, or one whose work occurs temporarily at one location before hemoves to another location. This context lends itself to a study of workers whodynamically redefine their workspace and move between various locations.

Spatially mobile workers can be explained by theoretical work (Lee andSawyer, 2002) that has tried to reconcile mobile work, time and space (Leeand Liebenau, 2000) in which new and old forms of work can be reflectedupon. This theoretical framework can be applied to mobility studies(Weilenmann, 2003) within boundaries that refer to ethnographical orethnomethdology research methods for the collection of data (Laurier, 2003;Luff and Heath, 1998 and 1999; Eost and Flyte; 1997).

The main research objective is to understand how the mobile worker definesthe categories for context of work and home as per using mobile technology inspatially mobile work.

To reach the research goal, the observations in the case study focuses onLondon Black Cab drivers working with mobile devices that are used toallocated task work: driving passengers from one destination to other. Thedrivers interviewed work mainly in the Central London area and are looselyassociated with radio taxi companies operating from centralized call centres.

To collect data, one-to-one interviews are the primary source of information sofar. Those interviews were conducted in diverse settings such as taxi ranks,taxi green sheds (used by drivers to have rest breaks) or public cafes and taxicall centre premises throughout London.

For the interviews we based our perspective on the value of the drivers’narrative and description. Hence the observations were made relying uponethnomethodology (Garfinkel, 1986). Drivers were allowed to express asmany ideas as they wanted regarding their work practices and the use ofmobile technology. For analysis purposes a high level of importance wasassigned to conversation analysis (Sacks, 1985) when building descriptivenarratives based on the interviews. This type of analysis can be applied withreference to all spaces of conversational interaction.

It is commonly pointed out that reflecting upon interviewed people might makethem feel uneasy or distort a naturalist approach to the interview (when usingtape recorders, or videos). However, this has not been a great problem inconversation analysis, since most drivers interviewed, if aware that they are

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being recorded got used to the idea, and stopped paying attention to therecording device some time into the interview (Denzin and Lincoln, 2003).

According to privacy legislation, all participants in this project were warned ofthe recording methods to be used and provided consent for the recordingsobtained.

Along those interviews we found that drivers were comfortable talking abouttheir family arrangements of their work schedules, allocations of work andanecdotic behaviour (story telling) of their shifts and/or rotas. This allowed theresearcher to identify diverse narratives recorded in the dialogues; categoriesand methods that defined the drivers work in terms of time and space. Someof those categories are work allocation, duration, sequence, deadline, rhythm,cycles, etc. And some of those methods are using voice calls, SMS (textmessaging), voice mail, etc. The researchers found that overall the driver’sconcern is primarily about themselves and how they go about producing theirown social order, which can be split between their work and home life.

Fieldwork with drivers in London Underground through video recording (Luffand Heath; 1999) showed that as the recorded image shows only the driver,the recording does not involve awareness from other persons. Recordingsonly include communication with the control centre; hence researchers’observations are properly focused on the underground train drivers’ activities.In the case of research involving taxi drivers we found that this interaction isdifferent: there is communication with a call centre, passengers (boarding,travelling, alighting), and other vehicles.

The taxi driver allocation of work is a product of the spatial position of theirvehicles and hence the need to use other complementary methods such asvideo recording their actives during their working days can enhance theunderstanding of which one of the key elements are their use of mobiletechnology in the context of spatially mobile work.

Another recommended field observation tool is the use of diaries (Laurier,2003). In this case, a researcher would encourage drivers to keep diaries inwhich they record their activities during their working day. Nevertheless, itremains difficult to assess to what level drivers are able to record allsignificant information requested, including time, position, and activityexecuted. Distortions over observations due to lack of accuracy might surge ifthis method is used together with other ways of observing mobile workers.With the use of diaries, the accuracy of records is not something theresearcher can control, however it should not distort the observation narrative(Denzin and Lincoln, 2003).

Using location technology such as GPS as a spatial locator over time hasbeen widely used by geographers and cartographers to determine thephysical location of objects or people (Laurier, 2003). The drawback of thismethod of tracing spatially mobile workers is that even if it gave a good spatialexplanation of the driver’s activity, it would remain impossible to determinewhat the driver is doing and the reasons behind the activity.

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This can be somehow balanced if the researcher gained access to drivers’calls recordings, in which time and duration are recorded. Together withdiaries and possibly some of the other methods discussed, this data canprovide valuable insight into research of spatially mobile workers.

External observations from the locations that the driver also uses to interactsuch as call centres or virtual spaces created by communicating with othersare also needed to get an overall view of the spatially mobile driver activities.We found that the most difficult task so far has been to establish thedifference between the static and virtual spaces taxi drivers move acrosswhen conducting work or other activities. This leads us to highlight the issuesregarding the level of access a researcher can have to his/her subject ofstudy.

2.1.1 Conclusions case study 1

To know where a driver is at a certain time does not give us the in-depthinsight of other factors (e.g., mental calculations of routes, where to go, howto get there, and overall how the use of mobile technology works in favour orto a disadvantage of the worker).

As stated, when collecting data regarding spatially mobile workers usingmobile technology, it is not possible to rely upon one of two data collectionmethods for a good understanding of the issues relevant to this type ofcontextual work. However, we have to be wary that since we are trying tonarrate within two major parameters such as time and space, someoverlapping, contradictions or even loss of observations might be expectedduring the data collection.

To identify the themes that recur in the spatially mobile worker over certaintime and space is a major issue for researchers in this field, as it is not alwayspossible to obtain information about all the activities the worker is engagedover a slot of time, or even if those events are cyclical and provide rhythms oftheir own to the workers activities.

2.2 Case study 2 – Following the mobile technology and mobile data

In an effort to understand the potential impact of novel technologicaldevelopments on organisational communication and cooperation, weembarked on two mobile telephony implementation cases that involved blue-collar workers from various industries.

As mentioned earlier in this document, a case study research method wasemployed to develop a conceptual discussion of mobile work practices. Inagreement with Benbasat (Benbasat, 1987), a case study is appropriate sincetheory and research are at their early, formative stages and since practicalexperiences and situated context are important. Clearly, this was the case forthe respective participants and technology used. Multiple data collectionmethods were adopted, including documentation, observation (non-

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participative), semi-structured interviews and logs of any mobilecommunication available. A focus on documents and interviewees’recollections on before-mobility and now will emphasise the principle ofanalysing the historical development of the activity. More generally, themultiple-case approach of looking at two organisations lends itself to internal(within-case) analyses of data to create initial assumptions about emergingschemes. Cross-case searches such as side-by-side comparisons of cases orof data sources will extend these initial assumptions and display patterns“through multiple lenses” (Eisenhardt, 1989). But here, too, differentmethodological approaches provide numerous challenges, as will be outlinedin the following research cases.

Workers from both cases cover hundreds of miles each day by travellingbetween customers’ sites. Their roles at these locations are mainly ensuringthat the on-site equipment is in working order, repairing it if it is not andrecording time-critical customer data. By and large, the data to be recorded isprovided from a number of devices (e.g., meters) installed on the customers’premises. Previous to the adoption of mobile technology, the workers reliedon the perennial clipboard: data was recorded on paper and submitted to theoffice via fax at midday and at the end of the workday.

Clearly, the problem of asynchronous data collection and transmission led tothe use of outdated and inappropriate data for customers’ resource allocationand for the despatching of mobile workers. This problem triggered theimplementation of the new mobile telephony system. In both cases, workersread the meters and entered the respective data into their mobile phone. Thereadings would then be transmitted to the main offices via SMS, at whichpoint they would be received by the backend system and update thecorporate database. Managers and clients could now view the data through abrowser interface and make much more educated and time-critical decisionsabout resource allocation.

The researcher set out to examine how such mobile work is carried out, andhow this technology lead to novel work practices of the workers underscrutiny. What observations support how the use of this mobile technologysystem leads to a change of work-practices? This question and casedescription leads us back to the methodological considerations mentionedabove. Even on a case-basis, how do we tell the full story of the individualsand organisations under investigation? More importantly, how do we interpretthe phenomena that we observe in our fieldwork? Can we tell a full story bylooking only at pieces? In co-located environments, this is already difficult.Distributed situations add more complexity to the study but mobile workersusing voice and data-driven technology make research extremely difficult.

In both cases, mobile workers relied on mobile phones and SMS tocommunicate with their peers and with their managers. The main difference isthat through SMS, we now have access to a technology that leaves a trace;communication that maintains some degree of permanence. Voice calls arerarely ever monitored or recorded for future analysis; they occur mostlybetween two individuals who exchange (and remember) their content. Once

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an SMS is sent from a mobile worker to the office, it enters a database systemthat relies on its ability to record, and to remember the data it receives. Notonly does this system remember the data transmitted from the meter that wasread, but it also stores data about the sender and the time of transmission. Incombination with the knowledge of the particular reader’s whereabouts, it alsohas the ability to store location-sensitive data of the mobile worker (if hesends the data as required – at the time of reading the meter).

Meter reading, entering data into the phone and sending these events to thecompany’s backend server comprise the core of these individuals’ work.Depending on the reading and the data, the server would then carry out anumber of responses: either it would send an SMS message back to theworker, relay a message via email to a manager or simply record the event forfuture data analysis.

In addition to these phenomena, particular pieces of equipment in the fieldwere equipped with sensors and autodialers. Under certain conditions, theautodialer would send a message to the above-mentioned database and tothe mobile worker assigned to its territory. In many occurrences during ourfieldwork, an engine would call the worker and order him to come to fix it orsend an SMS to convey that everything was ok. Clearly, this communication,too, shapes the work of mobile employees. Again, it is very clearly traceablethrough records of the autodialer and in the database.

As expected, mobile workers do not exclusively rely on SMS messages sentfrom pieces of equipment and sent to the office; they send messages to oneanother and make numerous voice-based calls to their colleagues, managers,family and friends. At the same time, the workers received phone calls notonly from artefacts but also from other humans. Supervisors would call tovalidate that certain jobs had been carried out, to check how long it wouldtake the worker to reach the next site, and in most cases to direct the workerto different, perhaps new sites. Other conversations were about work ingeneral. In addition to work related conversations, a high number of privatecalls would be made or received.In some of cases, the worker used the mobile phone handset to talk, in othersit was connected to the handsfree set mounted to the truck’s dashboard. Insome cases, the private handset conversation would last three minutes andbe summarised in one sentence, in other cases the worker would talk forthree minutes and take ten minutes to explain the nature and content of thecall.

2.2.1 Conclusion case study 2

Researchers trying to make sense of mobile phenomena will most likelyobserve situations in which some mobile occurrences are clearly of atemporary nature (e.g., workers talk on the phone), while others are morereproducible (e.g., SMS logs show exact event details, emails sent tomanagers from the backend system in response to a reading are logged etc.).Very clearly, all these events are part of our field data; they provide valuable

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insights into how mobile workers carry out their daily tasks and into theemergence of work practices.

When the time comes for we researchers to make sense of the data wecollected in the field, the question emerges as to how we combine the verydetailed and accurate records from data communication with ourtranscriptions of our incomplete exposure to some conversations and ouroften anecdotal accounts that form the other part of empirical fieldwork data.How do we combine our analyses if our empirical data is traceable to varyingextents? How do we incorporate data that is of varying degrees ofpermanence? How do we weight different data categories; or do we?

This paper provides no answer to these questions; on the contrary, it is itsintention to prepare mobility researchers for methodological challenges in theface of continuously changing technology and an increasing coexistence ofeasily available data logs and ambiguous voice-centred communication withno level of permanence.

2.3 Case Study 3 – Following the actor trying to understand the hostingprocess of mobile technology

The following case study aims to understand the hosting process of mobileand wireless Information technologies. This objective considers the concept ofHospitality proposed by Ciborra (Ciborra 1999 and 2002). According to thatconcept, Information Technology is like an ambiguous stranger that we host.“Hospitality is a human institution: it is about being receptive and adopting;managing boundaries between what or who is known and what or who isunknown” (Ciborra, 2002). When we allow the technology to remain in ourterritory, we can discover it as a friend or as an enemy. It can bring us a lot ofadvantages and desirable changes or instead a lot of problems. In the sameway, some people host and use mobile technology intensively while othersresist its use, for instance, because they believe that technology invades theirprivacy or is too difficult to use. This research tries to understand theseissues, questioning which are the main elements involved in the hostingprocess of mobile technology in organisations and how these elements areinterrelated.

This case study has been done within a Brazilian bank. This is a mediumorganisation in Brazil (with assets around US$ 2 billion). The bank operates inthe corporate sector, having as clients mainly middle and big enterprises. Weare studying the application of a smart phone (a device with PDA and Cellularphone functionalities) to access the bank’s Information Systems. Mainlysupervisors and account managers use this technology during their work atclients’ sites. This organisation was selected because it is a heavy adopter ofInformation Technology, and it was a pioneer in the use of mobile/wirelesstechnology in Brazil. The banking sector historically invests the largestamount of money in IT in Brazil.

The research has considered the principles for conducting interpretative fieldstudies in the IS area proposed by Klein and Myers (Klein and Myers, 1999).

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The data collection techniques employed include interviews with key-users ofthe mobile/wireless technology, managers and IT technicians as well as otheractors involved in the hosting process of the technology. We interviewedfourteen people in total, from the bank’s Headquarter in Sao Paulo and from abranch in a capital in the south of Brazil. Each interview lasted around onehour, some of them lasted around one hour and a half. Following therecommendations of Walsham (Walsham, 2003), the interviews were notrecorded, instead the researcher took notes of the conversation, andimmediately after each meeting she transferred the notes to an electronicdocument, where field notes were also registered. The researcher visited thebank’s headquarter in Sao Paulo four times and the branch in the south ofBrazil three times. At the same time, documents about the enterprise werecollected, including the manual of the mobile information system (targeted atusers of the mobile/wireless device), folders about the characteristics of theenterprise, its market and products, e-mails from clients and video recordings.Besides that, an interview was conducted with an external expert in theBrazilian banking sector, which provided an external view of the case and itsvarious contextual properties. There are also a lot of secondary documentsabout the bank in the Brazilian press that were collected.

However, we had difficulty with collecting data by following the user.Weilenmann claims that the study of mobility could demand to follow the userin the field, to observe how the mobile technology has been actually used in anatural setting. We were not able to do that. The nature of the work of theAccount Managers implies confidentiality during the interaction andnegotiations with the clients, in the field. Account Managers visit their clientsin their companies; it was impossible for the researcher to follow them as thiswas seen as a breach of banker-client confidentiality that would have negativeeffects on their activities.

We were just able to observe the use of the mobile/wireless device during theinterviews. Several users kept their devices switched on and sometimes theyexcused themselves for having to answers calls or short messages (SMS, e-mail) during the conversation. Some of them, when asked about the way thatthey use the technology, showed us how they use it by operating the device infront of us. That was the way we observed the use of the technology.

We recognize that this brought limitations to the data collection. The observeduse was stationary, and not “on the go”; and it was impossible to observe theactual use of technology in the field, as a tool used for daily activities.

2.3.1 Conclusion case study 3

Considering the case presented, we propose some questions regarding thecharacteristics of some types of mobile work that are very interesting forresearch, as the case of Account Managers in the banking sector. The mostimportant question is: How to manage privacy and confidentiality challengeswhen researching and observing work?

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We think that the most important question regarding “following the user” is:how to manage to not severely disturb the user, or to preserve the features ofconfidentiality of a work happening in the field? An Interpretative approachrelies on the assumption that the data is constructed through the interactionbetween researchers and participants (Klein and Myers, 1999). This meansthat the researcher will always, in some way, intervene in the context andsubjects been studied. How to deal with these implications when we faceissues related to privacy and confidentiality in the context of study of mobility?The case presented and the questions proposed highlight the difficulties facedwhen studying mobility. These limitations could be related to researchingseveral kinds of mobile workers, such as, for instance, health careprofessionals attending to patients in the field, due to the very confidentialfeature of individual health information.

3. Acknowledgements

As shown in the three case studies on this article, mobile studies present amethodological challenge when addressing empirical research. The challengeis not a theoretical one, but a practical one. Further research and completionof the current case studies will enhance our knowledge in this area.

Jan Kietzmann and Silvia Elaluf-Calderwood would like to acknowledge thesupport provided by the Mobility Group at the Information SystemsDepartment at the LSE.

Amarolinda Zanela Saccol would like to acknowledge CAPES (Ministry ofEducation –Brazil) for the scholarship received during her Visiting StudentProgramme at the London School of Economics.

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