29 January, 2014
Once upon a time, Streetmap.co.uk was one of the most popular Web Mapping sites in the UK, competing successfully with the biggest rival at the time, Multimap. Moreover, it was ranked second in The Daily Telegraph list of leading mapping sites in October 2000 and described at ‘Must be one of the most useful services on the web – and it’s completely free. Zoom in on any UK area by entering a place name, postcode, Ordnance Survey grid reference or telephone code.’ It’s still running and because of its legacy, it’s around the 1250 popular website in the UK (though 4 years ago it was among the top 350).
So far, nothing is especially noteworthy – popular website a decade ago replaced by a newer website, Google Maps, which provide better search results, more information and is the de facto standard for web mapping. Moreover, already in 2006 Artemis Skaraltidou demonstrated that of the UK Web Mapping crop, Streetmap scored lowest on usability with only MapQuest, which largely ignored the UK, being worse.
However, recently, while running a practical session introducing User-Centred Design principles to our MSc in GIS students, I have noticed an interesting implication of the changes in the environment of Web Mapping – Streetmap has stopped being usable just because it didn’t bother to update its interaction. By doing nothing, while the environment around it changed, it became unusable, with users failing to perform even the most basic of tasks.
The students explored the mapping offering from Google, Bing, Here and Streetmap. It was fairly obvious that across this cohort (early to mid 20s), Google Maps were the default, against which other systems were compared. It was not surprising to find impressions that Streetmap is ‘very old fashioned‘ or ‘archaic‘. However, more interesting was to notice people getting frustrated that the ‘natural’ interaction of zooming in and out using the mouse wheel just didn’t worked. Or failing to find the zoom in and out buttons. At some point in the past 10 years, people internalised the interaction mode of using the mouse and stopped using the zoom in and out button on the application, which explains the design decision in the new Google Maps interface to eliminate the dominant zoom slider from the left side of the map. Of course, Streetmap interface is also not responsive to touch screen interactions which are also learned across applications.
I experienced a similar, and somewhat amusing incident during the registration process of SXSW Eco, when I handed over my obviously old laptop at the registration desk to provide some detail, and the woman was trying to ‘pinch’ the screen in an attempt to zoom in. Considering that she was likely to be interacting with tablets most of the day (it was, after all, SXSW), this was not surprising. Interactions are learned and internalised, and we expect to experience them across devices and systems.
So what’s to learn? while this is another example of ‘Jacob’s Law of Internet User Experience‘ which states that ‘Users spend most of their time on other sites’, it is very relevant to many websites that use Web Mapping APIs to present information – from our own communitymaps.org.uk to the Environment Agency What’s in Your Backyard. In all these cases, it is critical to notice the basic map exploration interactions (pan, zoom, search) and make sure that they match common practices across the web. Otherwise, you might end like Streetmap.
Following the two previous assertions, namely that:
‘you can be supported by a huge crowd for a very short time, or by few for a long time, but you can’t have a huge crowd all of the time (unless data collection is passive)’ (original post here)
‘All information sources are heterogeneous, but some are more honest about it than others’ (original post here)
The third assertion is about pattern of participation. It is one that I’ve mentioned before and in some way it is a corollary of the two assertions above.
‘When looking at crowdsourced information, always keep participation inequality in mind’
Because crowdsourced information, either Volunteered Geographic Information or Citizen Science, is created through a socio-technical process, all too often it is easy to forget the social side – especially when you are looking at the information without the metadata of who collected it and when. So when working with OpenStreetMap data, or viewing the distribution of bird species in eBird (below), even though the data source is expected to be heterogeneous, each observation is treated as similar to other observation and assumed to be produced in a similar way.
Yet, data is not only heterogeneous in terms of consistency and coverage, it is also highly heterogeneous in terms of contribution. One of the most persistence findings from studies of various systems – for example in Wikipedia , OpenStreetMap and even in volunteer computing is that there is a very distinctive heterogeneity in contribution. The phenomena was term ‘Participation Inequality‘ by Jakob Nielsn in 2006 and it is summarised succinctly in the diagram below (from Visual Liberation blog) – very small number of contributors add most of the content, while most of the people that are involved in using the information will not contribute at all. Even when examining only those that actually contribute, in some project over 70% contribute only once, with a tiny minority contributing most of the information.
Therefore, when looking at sources of information that were created through such process, it is critical to remember the nature of contribution. This has far reaching implications on quality as it is dependent on the expertise of the heavy contributors, on their spatial and temporal engagement, and even on their social interaction and practices (e.g. abrasive behaviour towards other participants).
Because of these factors, it is critical to remember the impact and implications of participation inequality on the analysis of the information. There will be some analysis to which it will have less impact and some where it will have major one. In either cases, it need to be taken into account.
Following the last post, which focused on an assertion about crowdsourced geographic information and citizen science I continue with another observation. As was noted in the previous post, these can be treated as ‘laws’ as they seem to emerge as common patterns from multiple projects in different areas of activity – from citizen science to crowdsourced geographic information. The first assertion was about the relationship between the number of volunteers who can participate in an activity and the amount of time and effort that they are expect to contribute.
This time, I look at one aspect of data quality, which is about consistency and coverage. Here the following assertion applies:
‘All information sources are heterogeneous, but some are more honest about it than others’
What I mean by that is the on-going argument about authoritative and crowdsourced information sources (Flanagin and Metzger 2008 frequently come up in this context), which was also at the root of the Wikipedia vs. Britannica debate, and the mistrust in citizen science observations and the constant questioning if they can do ‘real research’.
There are many aspects for these concerns, so the assertion deals with the aspects of comprehensiveness and consistency which are used as a reason to dismiss crowdsourced information when comparing them to authoritative data. However, at a closer look we can see that all these information sources are fundamentally heterogeneous. Despite of all the effort to define precisely standards for data collection in authoritative data, heterogeneity creeps in because of budget and time limitations, decisions about what is worthy to collect and how, and the clash between reality and the specifications. Here are two examples:
Take one of the Ordnance Survey Open Data sources – the map present themselves as consistent and covering the whole country in an orderly way. However, dig in to the details for the mapping, and you discover that the Ordnance Survey uses different standards for mapping urban, rural and remote areas. Yet, the derived products that are generalised and manipulated in various ways, such as Meridian or Vector Map District, do not provide a clear indication which parts originated from which scale – so the heterogeneity of the source disappeared in the final product.
The census is also heterogeneous, and it is a good case of specifications vs. reality. Not everyone fill in the forms and even with the best effort of enumerators it is impossible to collect all the data, and therefore statistical analysis and manipulation of the results are required to produce a well reasoned assessment of the population. This is expected, even though it is not always understood.
Therefore, even the best information sources that we accept as authoritative are heterogeneous, but as I’ve stated, they just not completely honest about it. The ONS doesn’t release the full original set of data before all the manipulations, nor completely disclose all the assumptions that went into reaching the final value. The Ordnance Survey doesn’t tag every line with metadata about the date of collection and scale.
Somewhat counter-intuitively, exactly because crowdsourced information is expected to be inconsistent, we approach it as such and ask questions about its fitness for use. So in that way it is more honest about the inherent heterogeneity.
Importantly, the assertion should not be taken to be dismissive of authoritative sources, or ignoring that the heterogeneity within crowdsources information sources is likely to be much higher than in authoritative ones. Of course all the investment in making things consistent and the effort to get universal coverage is indeed worth it, and it will be foolish and counterproductive to consider that such sources of information can be replaced as is suggest for the census or that it’s not worth investing in the Ordnance Survey to update the authoritative data sets.
Moreover, when commercial interests meet crowdsourced geographic information or citizen science, the ‘honesty’ disappear. For example, even though we know that Google Map Maker is now used in many part
s of the world (see the figure), even in cases when access to vector data is provided by Google, you cannot find out about who contribute, when and where. It is also presented as an authoritative source of information.
Despite the risk of misinterpretation, the assertion can be useful as a reminder that the differences between authoritative and crowdsourced information are not as big as it may seem.
Looking across the range of crowdsourced geographic information activities, some regular patterns are emerging and it might be useful to start notice them as a way to think about what is possible or not possible to do in this area. Since I don’t like the concept of ‘laws’ – as in Tobler’s first law of geography which is stated as ‘Everything is related to everything else, but near things are more related than distant things.’ – I would call them assertions. There is also something nice about using the word ‘assertion’ in the context of crowdsourced geographic information, as it echos Mike Goodchild’s differentiation between asserted and authoritative information. So not laws, just assertions or even observations.
The first one, is rephrasing a famous quote:
‘you can be supported by a huge crowd for a very short time, or by few for a long time, but you can’t have a huge crowd all of the time (unless data collection is passive)’
So the Christmas Bird Count can have tens of thousands of participants for a short time, while the number of people who operate weather observation stations will be much smaller. Same thing is true for OpenStreetMap – for crisis mapping, which is a short term task, you can get many contributors but for the regular updating of an area under usual conditions, there will be only few.
The exception for the assertion is the case for passive data collection, where information is collected automatically through the logging of information from a sensor – for example the recording of GPS track to improve navigation information.
10 December, 2013
There is something in the physical presence of book that is pleasurable. Receiving the copy of Introducing Human Geographies was special, as I have contributed a chapter about Geographic Information Systems to the ‘cartographies’ section.
It might be a response to Ron Johnston critique of Human Geography textbooks or a decision by the editors to extend the content of the book, but the book now contains three chapters that deal with maps and GIS. The contributions are the ‘Power of maps’ by Jeremy Crampton, a chapter about ‘Geographical information systems’ by me, and ‘Counter geographies’ by Wen Lin. To some extent, we’ve coordinated the writing, as this is a textbook for undergraduates in geography and we wanted to have a coherent message.
In my chapter I have covered both the quantitative/spatial science face of GIS, as well as the critical/participatory one. As the introduction to the section describes:
“Chapter 14 focuses on the place of Geographical Information Systems (GIS) within contemporary mapping. A GIS involves the representation of geographies in digital computers. … GIS is now a widespread and varied form of mapping, both within the academy and beyond. In the chapter, he speaks to that variety by considering the use of GIS both within practices such as location planning, where it is underpinned by the intellectual paradigm of spatial science and quantitative data, and within emergent fields of ‘critical’ and ‘qualitative GIS’, where GIS could be focused on representing the experiences of marginalized groups of people, for example. Generally, Muki argues against the equation of GIS with only one sort of Human Geography, showing how it can be used as a technology within various kinds of research. More specifically, his account shows how current work is pursuing those options through careful consideration of both the wider issues of power and representation present in mapping and the detailed, technical and scientific challenges within GIS development.”
To preview the chapter on Google Book, use this link . I hope that it will be useful introduction to GIS to Geography students.
27 August, 2013
An interview by Prof Anthony Costello of UCL Institute of Global Health, discussing the growth in citizen science today.
During the symposium “The Future of PGIS: Learning from Practice?” which was held at ITC-University of Twente, 26 June 2013, I gave a talk titled ‘Keeping the spirit alive’ – preservations of participatory GIS values in the Geoweb, which explored what was are the important values in participatory GIS and how they translate to the Geoweb, Volunteered Geographic Information and current interests in crowdsourcing. You can watch the talk below.
To see the rest of the presentations during the day, see https://vimeo.com/album/2475389 and details of the event are available here http://www.itc.nl/Pub/Events-Conferences/2013/2013-June/Participatory-GIS-Symposium.html