Po Ve Sham - Muki Haklay’s personal blog

This week, we have released the ‘Suburban Town Centres Profiler’. The application can be accessed from the Towards Successful Suburban Town Centres website, and was originally developed to support hypotheses development within the project’s team. It’s been quite a while that we’ve been working on the range of maps and information the profiler is based on, practically since last summer.

All the details about the profiler are on its website, but an interesting point that underpins it is that, in some cases, it is worth sacrificing the interactivity of the map itself to allow users to concentrate on the information. In HCI terminology, the main task is not about interaction with the map but with the information and its meaning, so providing interactive maps will actually reduce the usability of the application!

The maps on the profiler do not support zoom in, zoom out or panning. However, they are not meant to be interactive by themselves. The idea behind the application is to allow systematic and consistent comparison of many layers of geographic information across a range of 26 town centres in London’s suburbs. To achieve this task, the interface allows us to switch between themes and explore various datasets quickly, and, by ‘locking’ the map itself, we can ensure that we are looking at each Town Centre at the same scale and to the same extent. I’m sure that there are other cases where such an approach is the correct one – not all interactions are necessarily helpful to the user’s task…

MySociety’s FixMySteet is somewhat similar – it is holding the scale constant while allowing Panning.

The Manifold training course that we ran earlier in February is always an excellent opportunity to observe how new GIS users interact with such a system.

Running a training session for new users of any GIS will expose major usability problems with the interface. Many of these problems are unnoticeable to experienced users, since they have learned the idiosyncratic aspects of the interface. Usability problems surface in such a session through misunderstandings and questions that the participants raise.

With Manifold, one of the interesting problems that came up is with the query toolbar (see below):

The way the query toolbar works is that you select a field in the left drop-down list, an operator at the central drop-down and a value in the text box on the right and click on select to see the result. For example, if you enter 5 in the toolbar in the picture, it will lead to a selection of the 5 polygons on the map with the smallest area.

The confusing part of the interface is the ‘not’ between the left drop-down and the central one. For a new user, the interface reads ‘find objects on the map where the field Area (I) are not the bottom X’. The ‘not’ in this case is a toggle button that can be activated to negate the operation that was selected in the central drop-down. Clearly, it would be better if, when not activated, it had the word ‘is’ (Area is the bottom 5) and ‘not’ appeared only when it was active. This is one of the cases where usability enhancement could be carried out in less than a minute of a programmer’s time – and surely makes life less confusing to many novice users…

During the visit to Turin, I had an opportunity to experience the consequences of address matching and georeferencing which I’ve noted in the entry ‘British Museum Test’. After touring the city, I needed to get to a restaurant to meet colleagues that were staying in the Institute for Scientific Interchange (ISI) in Turin. The meeting place was the ‘Il Porto di Savona’ restaurant in Piazza Vittorio Veneto 2. Since the hotel room was connected to the Internet through a relatively slow ‘Swisscom Hospitality Service’ connection, I decided to try to find my way to the restaurant with Google Maps, which are the fastest to download.

My first attempt with Google was unsuccessful – trying to search for ‘Piazza Vittorio Veneto 2, Turin’ pointed me to a place 10 miles away from the city. The next attempt was with Yahoo! Maps, but this one could not find anything. Microsoft Virtual Earth failed to find the full name, but offered a location called ‘Piazza Vittorio’ which I selected, only to zoom in and discover that the full proper name does appear on the map! Using this name (‘Piazza Vittorio’) with Google also worked and it managed to find the location.

Interestingly, because the connection was relatively slow, the interface of Microsoft was fairly annoying as parts failed to upload, and I was deterred from using Multimap as I’ve experienced slow response in the past on a fast broadband connection at home. Even so, checking more recently with Multimap shows that it will direct you to the wrong place in the city – although again, if you zoom to the map, the square is clearly mapped with its proper name…

The experience demonstrated how significant the problem of georeferencing is on these public mapping sites. This is a fundamental problem for these search engines to make them really usable. In this case, I used my knowledge of the range of public mapping sites, manipulated the address until I got the location and did a lot of things that, I suspect, a less experienced user would not do. I persevered with the problem because of my interest in usability and because it was an interesting problem. Actually, in terms of efficiency, it would have taken me less time to just go downstairs and ask the concierge…

Another aspect is that download time still matters. This is an aspect that web designers tend to ignore. I suspect that the assumption here is that broadband connections are ubiquitous. The speed of downloading a page is significant in geospatial applications – because there is no way round the fact that, unlike text based sites, the map is the most significant part and must be delivered as graphic files which tend to bulk-up the overall size of the page, as far as the end-user is concerned.

I must note that once I managed to find the location, it was again a pleasure to use the old style tourist map to navigate to and from the restaurant, which, by the way, I warmly recommend.

Map reading and navigation can be challenging – personally, finding my location on the map when touring a new place is not always easy. As a result, I thought for many years that having a device that could guide me ‘home’ would be really useful. Of course, away from home, ‘home’ may mean the hotel that I’m staying in. Today, it is possible to have such a device, as many smartphones are capable of finding their location and use services such as Google Maps.

A recent visit to Turin (Torino) made me rethink this view. The hotel I stayed in provided a typical tourist map (see example below) with a delightful depiction of the buildings in the centre of the city, clearly marked tourist attractions and, as always, some additional information on the back of the map.[ The map was produced by A&C e Turismo Torino ]

Touring the centre of a new place is a very enjoyable activity, and I realised that I didn’t want to get from the hotel to the centre in the most direct and efficient way. I really enjoy in looking in shops, public buildings, markets and other urban features along the way. Also, the fact that the map covered a large area at ‘high information density’ (the amount of information per square inch of interface area), because the printing is 6 to 10 times denser than a computer screen and arguably 60 times the area that is covered by the best smartphone screen, enabled me to see the ‘big picture’ and to notice more or less where I was heading. Instead of navigation by following a specific street, I was using the map to provide me with the general direction.

Nothing of the above is new, but, when I consider my experience and the enjoyment of touring a city and compare it to the current provision in navigation devices, I can see how much they are capable of spoiling the enjoyment of getting lost. Maybe the smart compass, as suggested by Max Egenhofer, can be useful for keeping the experience without destroying the really enjoyable aspects of it.

For a more general comment in the same vein, see Don Norman’s discussion in the recent ACM ‘Interactions’ journal for a more general complaint about devices and services which can destroy certain human enjoyments.

Back in 2005, when I worked with Artemis Skarlatidou on an evaluation of public mapping websites, we came up with a simple test to check how well these search sites perform: Can a tourist find a famous landmark easily?

The reasoning behind raising this question was that tourists are an obvious group of users of public mapping sites such as Multimap, MapQuest, Yahoo! Maps, Microsoft’s Virtual Earth or Google Maps. Market research information presented by Vincent Tao from Microsoft in a seminar a year ago confirmed this assumption.

During the usability evaluation, we gave the participants the instruction ‘Locate the following place on the map: British Museum: Great Russell Street, London, WC1B 3DG’. Not surprising, those participants who started with the postcode found the information quickly, but about a third typed ‘British Museum, London’. While our participants were London’s residents and were used to postcodes as a means of stating an address precisely, a more realistic expectation from tourists is that they would not use postcodes when searching for a landmark.

In the summer of 2005 when we ran the test, the new generation of public mapping websites (such as Google Maps and Microsoft Virtual Earth) performed especially bad.
The most amusing result came from Google Maps, pointing to Crewe as the location of the British Museum (!).

The most simple usability test for a public mapping site that came out of this experiment is the ‘British Museum Test’: find the 10 top tourist attractions in a city/country and check if the search engine can find them. Here is how it works for London:

The official Visit London site suggests the following top attractions: Tate Modern, British Museum, National Gallery, Natural History Museum, the British Airways London Eye, Science Museum, the Victoria & Albert Museum (V&A Museum), the Tower of London, St Paul’s Cathedral and the National Portrait Gallery.

Now, we can run the test by typing the name of the attraction in the search box of public mapping sites. As an example, here I’ve used Yahoo! Maps, Google Maps, Microsoft’s Virtual Earth and Multimap. With all these sites I’ve imitated a potential tourist – I’ve accessed the international site (e.g. maps.google.com) and panned the map to the UK, and then typed the query. The results are:

Notice that none of these search engines managed to pass the test on all the top ten attractions, which are visited by millions every year. There is a good reason for this – geographical search is not a trivial matter and the semantics of place names can be quite tricky (for example, if you look at a map of Ireland and the UK, there are two National Galleries).

On the plus side, I can note that search engines are improving. At the end of 2005 and for most of 2006 the failure rate was much higher. I used the image above in several presentations and have run the ‘British Museum Test’ several times since then, with improved results in every run.

The natural caveat is that I don’t have access to the server logs of the search engines and, therefore, can’t say that the test really reflects the patterns of use. It would be very interesting to have Google Maps Hot Trends or to see it for other search engines. Even without access to the search logs though, the test reveals certain aspects in the way that information is searched and presented and is useful in understanding how good the search engines are in running geographical queries.

By a simple variation of the test you can see how tolerant an engine is for spelling errors, and which one you should use when guests visit your city and you’d like to help them in finding their way around. It is also an indication of the general ability of the search engine to find places. You can run your own test on your city fairly quickly – it will be interesting to compare the results!

For me, Microsoft Virtual Earth is, today, the best one for tourists, though it should improve the handling of spelling errors…

As part of the Mapping Change for Sustainable Communities project, we organised the first workshop in the Royal Docks area, at the Sunborn Yacht Hotel last Saturday (27/10). The workshop was very successful and, as I usually do in these workshops, I start with ‘what mapping information can we find on the WWW about your locality’. I’ve been doing it now for about 7 or 8 years, but during the period, the Environment Agency’s Pollution Inventory maps never failed me as an example for technocratic dissemination of information which is not helping the people on the ground.

I find that, in all these workshops with people from many communities across London, very few knew about the Environment Agency information, let alone ever accessed it independently had. As the participants are usually from community or environmental interest groups, they are interested in the information – they just don’t know where to find it. I associate this lack of awareness with the fact that users find the information unfriendly and unhelpful, so there is no ‘word of mouth’ effect that leads to more use of the site. As someone in our Saturday workshop declared, ‘these maps are not written in community language or for community use’ – yet, they tick all the boxes of the Aarhus convention…

To understand what’s wrong, see the image below, which provides a view of the site on an average monitor (1024×768):

The header area is so big that all that is left is a fairly small area for the map.

Furthermore, as the full image of the page shows, the map is supposed to offer several layers of pollution data (on the right-hand side) but, as many of the layers include point data about the same site – all using the same symbols which overlap one another – the user can’t see if, in a given location, there is information from multiple categories.

The area of the map is very small (less than 400×400 pixels), and people find it very difficult to locate where they are or where the postcode is that they have selected in relation to the information on the map. Zooming in to the largest scale, or at any stage during the process, the system will run a query and provide information about the specific location only if the ‘learn more’ option is selected. Even as a more frequent user, I fail to click on this option and find the interaction with the system frustrating.

This site demonstrates that the Aarhus model of access to information, which is ‘we’ll build it and they’ll come’, is not sufficient and that a more user-centred approach is required to achieve public access to environmental information.

UCL’s licence for Manifold GIS 8.0 finally arrived. While testing the new 64-bit version I was reminded of one of the interface features of Manifold that I believe many other GIS should have as standard – a request to verify projections when a new component is added to the project.

One of the most confusing issues for new GIS users is to use projections within their workflow. Nowadays, it is common to integrate data from different sources, such as information gathered by GPS receivers with data from the Ordnance Survey, or any other data that is using a local projection. Therefore, it is important to ensure that the system ‘knows’ what the projection of each layer and image is.

Without proper configuration when trying to put all the data together, it doesn’t work because the projection of one layer doesn’t match another layer.

In Manifold GIS, when an image or vector layer is imported, when it is opened for the first time, the system asks the user to verify the projection, and opens the interface that allows the assignment of the current projection. Unfortunately, Manifold GIS does not give the option to set the most common the default projection for the locale in which the system is used – or at least set a group of favourite projections. Room for improvement there!

As for Manifold GIS 64 bit – it seems to work faster, although it was a surprise to see that in some operations the 4 cores were not busy at 100% or even 50% even though the system loads the data slowly. Apart from that, Windows Vista 64 bit is quite incompatible with many legacy applications and it is quite a pain to use. Maybe it’s time to return to Windows XP…

One of the questions that might arise from a look at my publications and work is ‘how public access to environmental information links to GIS, and what are the reasons to explore usability and HCI in this context?’

The answer is straightforward – there are strong links between all 3 areas and, in order to make sense of one of them, you need the others. In my 2001 paper ‘Public access to environmental information: past, present and future’ I go into more details , but here is my current summary of the issue.

One of the core concepts of environmental decision making is the use of information. In current environmental debates you can see how much opponents dispute the accuracy and validity of information, but rarely dispute the need for information or the role of information in decision making. This approach to information in decision making can be traced back more than 40 years, and has been a constant feature of environmental politics.

The next element in the chain is Geographical Technologies – GIS, Remote Sensing, ground-based monitoring and the like. One of the features of environmental information is the heavy reliance on these technologies that, historically, the environmental field adopted early on. For example, consider the following (rephrased) paragraph:

‘Existing technology now makes possible the development of a global resource data base (GRID), which will be a data management service designed to convert environmental data into information usable by decision makers. The technical feasibility of GRID has been assessed by expert groups.

‘GRID technology allows us initially to describe, eventually to understand and ultimately to predict and manage the environment.’

This is not a description of Digital Earth or from a specification document of Google Earth – it is based on UN Environmental Programme documents from 1985 and 1986, when the GRID system was in its first stages. Even today we don’t have anything like the system that is outlined above. Was it a visionary view of the potential of GIS or yet another example of technophilia? In any case, it shows the strong link between GIS and environmental information.

The next element is usability and Human-Computer Interaction. GIS are hard to use (more about this in other posts) and the reliance on them to deliver information creates real obstacles for occasional users – which most users are. I have observed the difficulties of intelligent and competent people during workshops where they were faced with the task of using GIS or web mapping technologies. That’s where my interest in this area emerged.

In summary, the challenge of providing environmental information to the public is not just the technical one of making it available over the Internet – without understanding how to make GIS more accessible for the average user and understanding which are the most efficient, effective and enjoyable ways of helping people to use the information effectively, we can’t really deliver on the promises of the Aarhus convention on public access to information, participation and justice.