Trajectories as heuristics

I now describe how my colleagues and I used trajectories as heuristics to discuss and critique the design of an existing experience.

This process follows Steve Benford and Edward Anstead’s approach of “applying trajectories” to existing experiences. It was used with two BBC multiscreen experiences, the Antiques Roadshow and the Jigsaw app, and has been documented by its authors: the outcome of the first has been published as a zoomable presentation, and the methods and outcomes for the seconds has been formalized in a submission to the EuroITV conference (Anstead et al., 2013).

Figure 4.6: The Antiques Roadshow companion app, analysed as a canonical trajectory and published as a zoomable presentation. Created by Steve Benford on Prezi.

The method described in the paper is a nine-step process (see table below), modelled on the concept of usability heuristics in which different aspects of trajectories are considered.

Canonical Trajectories:

Step 1: Identify the core canonical trajectories in the experience Step 2: Map out the overall structure of each canonical trajectory Step 3: Identify key transitions along these trajectories

Step 4: Consider patterns of encounter between trajectories

Participant Trajectories:

Step 5: Explore possibilities for divergence Step 6: Consider the need for orchestration

Historic trajectories:

Step 7: Ensure that the experience can be documented Step 8: Support the telling and sharing of stories Step 9: Connect this back into repeat experiences

Table 4.1: Nine steps of applying trajectories to multi-screen TV experiences (from Anstead et al. 2013)

I applied that process to a tablet application that was deployed in a nature reserve and had inspired the “Walk in the Woods” scenario described in the previous sub-section. The Wild-I app supports a visiting experience by providing video content relating to different animals residing in the reserve, based on the tablet’s location (see screenshot below). It was developed as part of a research project involving multiple academic and industrial partners4 _{aimed at} investigating video delivery over wireless networks in public spaces.

Figure 4.7: A screenshot of the Wild-I app for the Bristol Zoo, from aiyponline.org

Within that partnership, the BBC was tasked with evaluating and documenting the user experience. They had therefore sent a team of researchers to the nature reserve, who were handing out questionnaires, conducting short interviews, and filming app users on location. I met with the research team and did observations, both by using the app myself, looking at others use the app, and asking for informal feedback from BBC researchers. After I came back from the nature reserve, I followed the evaluation heuristics to question the features of Wild-I, producing a report showing design guidelines elicited by applying these steps. I now reflect on the process. First, each of the steps did yield insight on the experience, although some were more productive than others. The “Identify key transitions” step was particularly useful, as I looked at seven different types of transitions. Second, there is some overlap between steps. For example, going out of the charted area could be treated under either the “Identify key transitions” heading or under the “Explore possibilities for divergence” one.

The first step, which is “identifying the core canonical trajectories” could have been done in a number of ways depending on my relationship with stakeholders and on how much I would consider myself as trying to improve a pre-existing canonical trajectory or proposing a whole new one. I took the first approach, and although there was no such canonical trajectory, I reconstituted it by combining information I had about the intent of the app and the app’s navigation structure with how visitor information at the reserve and on the wildlife trust’s website already prescribes a trajectory through the grounds. I looked at the trajectories of three roles in particular. These roles were based on discussions with the research team about target audiences. They are partly based on research commissioned by the wildlife trust about its visitors, and are consistent with the

types of visitors I’ve encountered while on location, and how the trust targets its communications.

Steps in the process that map with app features tend to show issues with these features. For example, considering seams in the infrastructure shows that GPS signal can’t be relied upon to pair content with location, a result previously highlighted in several works around trajectories (Fosh et al., 2013; Nisi et al., 2016). Other steps specifically call for new features to be added, such as “ensuring that the experience can be documented”. Finally, a number of steps use more careful language, phrased as aspects that need to be “considered” or “explored”. Addressing these steps is ambiguous not only because there may be more than one way of orchestrating an experience or supporting divergence, but also because these considerations need to take into account the value that trajectories may bring to the experience. As an example, trajectories call for encounters to be successively encouraged or discouraged depending on the script’s needs, but in Wild-I’s case, these needs (which could have involved the reserve managing crowds or promoting activities) hadn’t been elicited. This resulted in the evaluation resulting in a number of open questions, most importantly to what extent and for which purpose trajectories needed to be managed.

Finally, one important gap in these heuristics, when comparing them with the contents of the trajectory framework, is the lack of a step aimed at eliciting the four “dimensions of experience” – space, time, roles and interfaces – involved. Given that these heuristics cover evaluating the app as part of a trajectory, they don’t address general app usability issues (such as confusing navigation), although these might be discussed along transitions as usability may prevent transitions from happening or trigger early endings or dropouts.

A few months later, I was invited to participate in a second round of evaluations, this time at a zoo. Changes to the user interface, beyond adaptations for the new settings, only included minor tweaks, given that BBC R&D had little input in the design process and most of the design decisions had already been settled. On some aspects, trajectories were a good match for this type of project – thanks to the multiple locations, multiple roles, traversals between virtual and physical assets, and a path across a location that could serve as a canonical trajectory – but there were no opportunities for stakeholders – whose main ambitions were to trial networking technology and to promote an existing set of video content – to engage with the values of trajectories, for example with bringing a sense of a global narrative to the project.

4.6 Co-creating a card-based