Small Screen Access to Digital Libraries

Small Screen Access to Digital Libraries Gary Marsden, Robert Cherry & Alan HaefeleCollaborative Visual Computing Group,Department of Computer Science,University of Cape Town+27 21 650 2666gaz@cs.uct.ac.zaABSTRACTThis paper looks at the possibilities of taking existing digi-tal library technology and using it for educating those who do not normally have access to the Internet. We have built a system which allows WAP devices to access an HTML based digital library. Whilst building such a system is technically possible, our work has shown that there are a wide range of usability issues which need to be tackled. We investigate these problems, suggest improvements and out-line where future research needs to take place.KeywordsDigital libraries, digital divide, mobile interaction INTRODUCTIONThe research reported in this paper is based around building a mobile interface to the Greenstone digital library soft-ware1. Greenstone is robust, powerful, freely available and, most importantly for our work, is used by UNESCO to distribute their collections of humanitarian information. Being based in South Africa, we are interested in making the information contained in these collections available to the widest possible audience. Given the low rates of tele-density in South Africa, a straightforward, Web-based solu-tion will not suffice.DistributionThe ability of Greenstone to burn CD-ROM versions of its collections goes some way to overcoming the problems of poor Internet access. To be useful, however, the recipient must possess a computer with a CD-ROM drive; some-thing which is not available to most rural South Africans. Strangely, the technology most available to South Africans are cellular telephone handsets. In a country where only 11% of the population are registered tax payers[5], some 22% own cellular handsets[2]. With the introduction of a third service provider (November 2001) and a reduction in tariffs, access to cellular services is continuing to grow.1 /There are a number of reasons for this, but perhaps two of the strongest are:Poor land based infrastructure: South Africa still has a tele-communications monopoly which has led to poor services and tariffs being higher than cellular for non-local calls. Urbanisation is still increasing in South Africa, so a large percentage of the population have no fixed abode from which they could access land based telecommunications. Cellular communication better suits an itinerant lifestyle. Given these facts, we decided that the best way to provide access to the UNESCO resources was through WAP en-abled cellular handsets.WAPA lot has been written about the usability of WAP: some analysis coming down heavily against it [4] and some less damning[1]. However, in this situation we do not have the luxury of issuing our clients with new GPRS or GSM en-abled PDAs or tablet PCs. In fact, as WAP handsets are superseded in developed economies, it is likely that they will become prevalent in our local market. We therefore set about investigating the possibility of providing full access to Greenstone using nothing more than WAP and WML. All interaction with Greenstone is currently conducted via HTTP and HTML. To bridge the gap with WAP and WML, we implemented a proxy server, details of which can be found in [3]. We were able to generate sensible WML as the Greenstone content is well defined and regular in structure. Having built the server, we had to tackle a variety of usability issues which are not easily solvable. Each issue was tackled using heuristic evaluation with a selection of Web literate users (who were not familiar with digital libraries per se).Document StructureSimple problemsDigital library documents tend to be arranged in a hierar-chy: collection, document, chapter, section etc. There is a convention of indentation for showing this information. However, indentation on a WAP device is not easily achieved as several of the browsers we worked with ignore white space. After trying a variety of solutions we discov-ered that minus signs ‘-’ served to force indentation with-out cluttering the display.Also, when browsing Greenstone, only the section head-ings of a document are retrieved. On our system, we used a‘+’ symbol to denote an open branch and a ‘-’ symbol to denote a closed branch. This caused problems in the usabil-ity tests as users familiar with Windows Explorer associ-ated ‘+’ with the functionality to expand a branch and ‘-’with the function to close a branch. Once we altered the design to conform to Windows, users no longer stumbled on opening and closing branches.BrowserWe used several browsers in our evaluation and discovered that each had a different interpretation of the WML stan-dard. We found browsers whose back button did not work; browsers that would place buttons in arbitrary screen posi-tions and browsers that would not display hyperlinks longer than the screen width. Although these are implemen-tation issues, one usability issue common to most brows-ers was the indication of scrolling. When a page stretched over more than one screen, our users would often not scroll down. When asked about this, most responded they had no idea that there was more information (unless there was an uncompleted sentence or other accidental cue). The reason users did not scroll was related to the small size of the scroll bar on most WAP browsers. Designed to take up as little screen real-estate as possible, these widgets are barely noticeable, providing no feedback to the user on the length of the page. If usability of WAP is to improve, then scrolls bars need to remind users that more information may be hidden beyond the bottom of the screen.Digital librariesAfter watching our subjects struggle to retrieve information with our system, we conducted some usability tests with the full, HTML, version of Greenstone. Our results showed that some usability issues lay with Greenstone, rather than being artifacts of our system.As our target users have had little experience with libraries, let alone digital ones, we discovered that the basic meta-phor of information structure (i.e. chapter, section, sub-section etc.) proved problematic. We found two key prob-lems which stemmed from the disparity between the digital library and general Web search engines:Browsing: When a document is accessed in Greenstone, an outline is presented at the top of the screen. To go to a particular section, the user clicks the relevant part of the outline and the target text appears beneath the outline. This confused users who expected to be taken to a text only page, as would happen in a Web document.Searching: When the results of a free text search are re-turned in Greenstone, there can be different types of entry: chapter, books, document etc. (each denoted by a different icon). When one of these is selected, the user will be pre-sented with a different screen layout, depending on result type. Our users were confused by this, regardless of the icon, expecting to be taken to a new HTML page, as would happen in a Web search.If digital libraries are to make an impact beyond English speaking, computer literate users, then there are several interesting questions which need to be answered. What is clear, is that a simple translation (into a local language) of the interface will not be enough – more fundamental re-search is needed in to how information can be structured and presented to those not familiar with document conven-tions. Our preliminary work[6] has shown that many cul-tures have no concept of hierarchies of any kind (subjects were unable to draw a simple family tree). CONCLUSIONWe have implemented a system which exploits digital li-braries and cellular technology to make relevant informa-tion available to the widest possible community within South Africa. Whilst the technology is not a problem, our usability tests have shown that there are problems with WML, WML browsers and the organization of digital li-brary content.In the short term, we have adapted our system to follow the conventions of the Web and Web searching. This has greatly improved the usability of our system, to the extent that web-literate users can perform meaningful queries and retrieve useful results. The issues of WAP browser and digital library design still remain.We are confident that as mobile internet access becomes more common, the usability of mobile browser software will improve. The work of altering digital libraries for use in developing countries, however, has no direct commercial benefit and is only likely to happen, therefore, as an aca-demically motivated project. Unless the promise of the Internet as an empowering technology is to ring hollow in the developing world, we believe that we need to rethink such fundamental concepts as libraries before we can create interfaces which can start to close the digital divide. REFERENCES[1]Heylar, V. Usability Issues and User Perspectives of a1st Generation WAP Service. Proceedings of the Wire-less-World Symposium, 2000.[2]http://www.cellular.co.za/[3]Marsden, G., Cherry, R. and Haefele, R. Small ScreenAccess to Digital Libraries. Proceedings CHI-SA con-ference, 2001. (.za/CHI-SA2001/proceedings.htm)[4]Nielsen, J WAP backlash (2000) Alertbox, 09/07/2000at /alertbox/000907[5]Statistics-SA Census data, .za/[6]Walton, M., Marsden, G. and Vukovic, V. Key chal-lenges for project-based learning: A study of SouthAfrican student web searching strategies. Pro-ceedings CHI-SA conference 2001 (.za/CHI-SA2001/proceedings.htm。