The usability study was conducted through a questionnaire presented to each member of a diverse group (in terms of age, sex and previous fieldwork and computing experience) of thirty-eight ecology volunteers. The acceptance of the technology was unanimous with everyone preferring the prototype over traditional data collection methods, and most of the group feeling comfortable with the system in the first day of use. There was a small degree of worry about using the prototype before trying it, but after their two-week projects all worries were dispelled and most people were in fact looking forward to using the system again given the opportunity.
Very few people had problems using the PalmPilot itself and no one had any difficulties in using the prototype software. One feature in particular that was identified by users as enhancing the ease of use was the automatic recording of location data. The overall usability of the prototype, rated on a five point scale ranging from very difficult to very easy, was found by the vast majority of people to be easy or very easy. The general features that user’s said they liked most about the prototype centred on convenience: compact size, ease of data entry, the prompting of data to enter, and the ease of transcription. The only negative aspects were the resets required, the wish for an increase in speed by advanced users, and the battery charging logistics. The former two problems would be fixed in production quality software, and the latter could be rectified with self-charging internal batteries or simply better organisation of the charging process.
Given such positive feedback from the volunteers throughout the summer of trials we can confidently state that the usability of the tools has been a great success. However, these people are only one part of the equation: the ecology researchers must use the data collected from the tools, and also collect data with the tools themselves. We were already familiar with their very positive opinions on our tools from our early prototype work with them. Their interest in the tools led to this large field trial in the first place (they had requested to use our new tools to aid in data collection with this new volunteer-driven ecology project). They were pleased that, using the tools, the volunteer
Chapter 5: Fieldwork Tools Usability Study
data was indeed reliably and consistently collected and that it was available for immediate analysis after a simple download procedure.
5.5 Summary
We have performed a comprehensive usability study of the prototype in the field with a group of thirty-eight unbiased and diverse fieldwork volunteers over a period of eight weeks. In this chapter we firstly presented the structure of the fieldwork: pairs of volunteers performing various tasks over the course of a two week period, with teams of approximately ten people for each two-week period. We also described the diverse range of activities that each pair would be expected to carry out, ranging from rhino observation to elephant dung counting, and how the prototype would enable such activities through the recording of stick-e notes.
The benefits to the ecology project managers were clear from the outset: they would get immediate and effortless transcription of the recorded data into a spreadsheet (through a simple downloading procedure), the time and location data would be reliably recorded (because it was automatically extracted from a GPS receiver and system clock), the data collection would be performed in a consistent manner (via standard stick-e note templates and enforced data types and ranges), and the data could be easily secured (through various electronic backup strategies). However, we were also interested in how the prototype would be received by the volunteers actually performing the fieldwork. Therefore, to ascertain the usability of the tools in the field we gave each volunteer a questionnaire that aimed to capture their feelings and experiences of using the prototype. The results of an analysis of the data gathered were very positive: every single volunteer preferred the prototype to traditional methods, in particular citing features such as the ability to automatically record location data. Most users were comfortable using the prototype within the first day after only half an hour of training, and the majority were looking forward to using the prototype again in future projects. In conclusion, we can safely state that the prototype is certainly most useful, practical, and well received in real fieldwork projects.
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The usability study effectively demonstrated the ability of context-aware systems to help people in real world tasks and situations. However, it is rare to find such context- aware systems in use today due to the large development overhead incurred in imbuing software with a context-awareness. In effect there is a need for generic context-aware services that can be compared to the GUI services available for user-interface developers; imagine developing a user interface by manipulating individual pixels on the screen. As was the case with the development of common GUI services, we believe that the construction of context-aware services will encourage the adoption and an increasing sophistication of context-awareness.
The stick-e note framework was our first attempt at providing a context service, and the fieldwork tools were the first applications developed to utilise this service. In this chapter we describe the lessons that we have learnt from the development of this software, and re-examine our beliefs about the nature of context and the facilities a context-aware framework should provide. We go on to present the general concept of a
context information service and define its structure in terms of a layered model of context-
aware capabilities. Using this model we compare a number of research projects that are exploring context-aware services, and conclude with some suggestions as to the desirable characteristics that a good context information service will exhibit.
6.1 The Nature of Context
At the start of our work on context-awareness we had conceived of context as being a relatively simple snapshot of a set of environmental values such as location, temperature, time, etc., which described a particular instance of the user’s environment.
But as our work has progressed it has revealed a more rich and complex nature of context.
6.1.1 Context and Content May Not Be So Different
In our stick-e note framework we initially made a very clear distinction between context and content. This was understandable given our concepts of Post-It notes and tourist guides in which an item of data was electronically attached to a particular situation. However, in developing the data collection tools for the ecologists the difference became much less distinct. When using the tools they were just as interested in the context of the note (i.e. the location in which it was recorded) as they were in the behavioural observations that they recorded. Additionally, the information they recorded, such as the current activity of a giraffe, could be considered to be as much context as it was content. To them the only distinction between the content and context of a stick-e note was that the computer automatically completed the contextual parts.
We thus adjusted our concept of a stick-e note to accommodate this change of perception. Instead of two separate context and content parts, there is now simply a set of fields that describe a situation.
6.1.2 Context Can be Complex
Upon first consideration a context element such as location may appear to be a relatively simple item of data to manipulate. However, it soon becomes apparent that there is a plethora of different location sensing systems available such as GPS [Texas- University 1999 - #141], active badges [Want, Hopper 1992 - #145], visual identifiers [Rekimoto and Ayatsuka 2000 - #110], etc. These all tend to use their own measurement systems and work in different, though sometimes overlapping, domains. For example, GPS only works outdoors and tends to use latitude and longitude measurements, whereas active badges are more often deployed indoors (due to infrastructure costs) and use a cell-based measurement system. What is more, some of these individual measurement systems have different operational attributes that can dramatically affect their correspondence with the real world, e.g. latitude and longitude is expressed in relation to a specific datum (essentially, a mathematical representation of