Exploring geospatial data issues from the Global Souths perspective. Approaches, sources and methodologies
Francesco Curci, Alessandro Frigerio, Fabio Manfredini, Stefano Saloriani
Department of Architecture and Urban Studies, Politecnico di Milano
The objects of this contribution are, broadly speaking, geospatial data and analyses, whether or not they are overtly geographic information, whether they have public or private origin, whether they are freely accessible – potentially anywhere and by anyone – or subject to various kinds of restrictions.
The focus is placed rather on the different geographical scales (global, national, regional, urban, local) that characterize them, on the formats – which are nowadays fundamentally digital or digitalized – and on the IT and web environments and tools through which they can be consulted and processed.
Of great relevance is also the value attributed to such information by the different subjects (natural or legal, formal or informal, institutional or non-institutional entities) that collect, produce, validate, analyse, interpret, disseminate and use it. Depending on the case, this value can be political, economic, social, cultural, scientific, and technical, and it can certainly change in relation to the different types of activities to be performed: strategic, planning, programmatic, cognitive, marketing, experimental activities, etc.
Equally important is obviously the cultural and geographical context, with its variables and peculiarities, within which geospatial data and analyses originate and spread, just as their potential recipients with their different competences and aspirations are fundamental. In relation to this last point, the paper is addressed mainly, but not exclusively, to PhD students who make research in the field of urban and regional studies in the so-called countries of the South of the World.
The paper reflects on the role and methods of production, dissemination, use and exploitation of geospatial data and analyses adopting a point of view necessarily mediated by the constructs and systems that characterize the countries of the global North, but with a particular focus on those research activities that investigate the Global South environments and spaces. One of our objectives is to propose some precautions regarding the approach to take in relation to different data sources and issues and their treatment with reference to the countries of the South of the World. In fact, we believe that the scope, the size and the complexity of the question we are asked to address require us to put forward some clarifications about the way in which we approach on a global scale the question of data and its analysis, particularly urban and territorial data, together with a whole series of more strictly methodological considerations. The next section provides some considerations of general and theoretical nature, while all the other paragraphs are devoted to more practical examples about different ‘families’ of data that could be useful to explore when carrying on different urban research activities.
- Data and Global Souths, between capitalism imperatives and research purposes
To begin with, we need to spend a few words on the different meanings the concept of data assumes according to the geopolitical and socio-cultural contexts to which it refers, also and above all with respect to the economic and technological revolutions that occurred during the last decades. The starting point is to recognize in a broad sense that there is a profound link between the modern concept of data and the rationalism inherent in the scientific method but also in modern capitalism, as theorized by Max Weber. As known, both the scientific and the industrial revolution took place in Europe, and even the mediaeval proto-capitalism took shape in this precise geographical and cultural context. Both science and capitalism are therefore originally Western inventions. It is not a coincidence that the first examples of geospatial data and analysis were developed in the heart of neo-industrial Europe thanks to positivist, scientific (and bourgeois) impulses present at the time in some important capital cities such as Paris and London. We expressly think of the pioneering maps by Charles Piquet (1832) and John Snow (1854) developed to study the cholera epidemies in Paris and London, but also the subsequent London’s poverty maps by Charles Booth (1898-1899) [fig. 1, 2, 3].
Fig. 1 – Cholera map by Charles Picquet (48 districts, Paris, 1831)
Fig. 2 – Cholera map by John Snow (Soho District, London, 1854)
Fig. 3 – Poverty map by Charles Booth (Inner Wester District, London, 1898-9)
Leaving aside the relationship – much more evident and explored – between data and science, we want to try to reflect here more on the relationship between data and capitalism. This is because the same concept of the South of the World is strongly linked in a Weberian sense to this long-running phenomenon. Therefore, if it is true that the South of the World is the geopolitical and socio-cultural space in which modern capitalism has not yet become the only or prevalent mode of satisfying daily needs (Weber, 1923/1997, pp. 195 ss.), it becomes fundamental to understand how diffusion and extensive use of data, whatever it may be, even when dealing with experiences of anti-capitalist (and / or de-colonialist) data activism, are directly or indirectly connected to the way the capitalism reproduces itself, expands its influence and impacts on contemporary spaces and societies.
To address these arguments, one cannot ignore the specifics of the current phase that capitalism is going through, i. e. digital capitalism (Schiller, 1999; Fuchs, 2013) or platform capitalism (Srnicek, 2017). According to some scholars working in the field of so-called ‘critical data studies’, «when we map Big Data, we map the contours of capital» (Dalton, Taylor and Thatcher, 2016, p. 6). This poses obvious problems relating to the growth of inequalities at all scales, since «a great variety of ‘software-sorting techniques’ is now being widely applied in efforts to try to separate privileged and marginalized groups and places across a wide range of sectors and domains» (Graham, 2005, p. 562). It is interesting to note that according to these critical approaches the current differences in production, diffusion and access to data (in particular the ‘big data’, but not only) are not exclusively a consequence of the intrinsic structural differences between advanced contexts and backward contexts (such as the digital divide issue), but more likely they are also the sign of the absence of specific profit imperatives (Dalton, Taylor and Thatcher, 2016) and market strategies.
«Digital exclusion confirms capitalism’s selective interest in creating markets and exploiting labor. Not every population is equally attractive to capital. A totalizing push for data extractivism, driven either by corporate expansionism or state policies, would have improved digital access. However, just like previous forms of capitalism, digital capitalism selectively targets publics while completely ignoring others. It is not equally driven to monitor, track, and commoditize all populations. In a region with historically entrenched, abysmal levels of social inequality, digital exclusion is another form of social marginalization» (Segura and Waisbord, 2019, p. 416).
Studies that relate dataification (Van Dijck, 2014) and data justice are increasingly numerous and in some cases they place a strong emphasis on cities of the Global South and their specificities to investigate above all the risks for urban populations that are already marginalized (especially those living in informal areas) and who risk being further marginalized and under-represented. According to some scholars, the intrinsic power of knowledge structures and information flows have exacerbated existing divides and debased the Global South specific knowledge (Andrejevic, 2014; de Sousa Santos, 2014; Milan and Treré, 2019). Milan and Treré (2019, p. 324) argue that there is a growing necessity to question data universalism, i.e. «the tendency to assimilate the cultural diversity of technological developments in the Global South to Silicon Valley’s principles» and to go beyond it to avoid or mitigate what de Sousa Santos (2014) specifically defines epistemicide of the South.
Therefore, given this inexorable capacity of profit-linked mechanisms to determine the fate of the territories and populations that inhabit them, does it really make sense to wonder about other possible data regimes as an alternative to capitalism-driven ones? If this is the case, as we believe, then what are or must be the ethical imperatives (beside scientific ones, of course) to be placed at the base of alternative and complementary ways of collecting and disseminating data from subjects able to free themselves from capitalist domination (Dalton, Taylor and Thatcher, 2016)?
All these considerations and questions become crucial and urgent if we assume the thesis according to which in the XXI century the countries of the South of the World will progressively complete their process of assimilation to the capitalist model regardless of the specific forms that it will take. Accordingly it becomes important to recognize the specificity of the current situation – evidently the result of a phase of geopolitical and socio-cultural transition – and also to consider apparently negative facts – such as the lack of data or the inability to produce them like in the North of the World – in a possibilist, pluralist and anti-epistemic perspective. Perhaps also in the scope of urban and territorial studies, thanks to the techniques and methodologies typical of these disciplines, new practices and trajectories of production and use of data could be developed in the future in an alternative way to those of strictly capitalistic matrix. We know that this is already happening in various forms, but we are not able to establish whether even the most virtuous experiences will be able over time to subvert the dominant logics already mentioned. However, insisting on the search for a new data ethic remains something desirable at least to try to push away the spectre of data colonialism, but also that, certainly more misunderstood, of academic and professional colonialism.
We can now introduce the methodological issues on which we have decided to build this contribution based on the start of the work of the School of Global South. We must certainly begin by saying that we will base ourselves on the awareness that the work we are called to do as urban and regional scholars is now completely performed within the field of digitalization of processes, communications and social relationships. These are processes that, in addition to expanding our possibilities of knowledge, hide various ethical pitfalls. Therefore, when referring to geospatial data issue we have to recognize the existence of «two contradictory forces in contemporary digital societies: (1) data extractivism and surveillance driven by corporations and states and (2) the possibilities for citizens’ resistance and autonomy in late capitalism» (Segura and Waisbord, 2019, p. 412). Notwithstanding this evidence, since this contribution is strongly oriented to instruct concrete research activities, we do not intend to take sides with either one or the other force. We rather prefer to explore a wide range of sources and methodologies based on the actual availability and usability of information and tools within a conceptual framework based on the awareness of what they are and represent.
It is the intention of this contribution to provide some general coordinates on geospatial data, trying to recall terms and concepts from which to conduct more specific research in different geographical contexts. Providing a few key words, accompanied by some concrete examples, can be very useful since we are addressing an audience of young researchers with extremely different backgrounds, competences and abilities. Our aim is to increase awareness about the multifaced world of urban data and specifically of geospatial data. Our experience in the educational and training field tells us how some technical-methodological notions are not always guaranteed by the university educational offer and how the acquisition of certain notions should not be taken for granted even for students attending the same course degree program or for doctoral students of the same doctoral course. For this reason, we believe that this paper must fundamentally provide an overview of notional and terminological “realignment” even before being strictly methodological. In this sense, our contribution intends to provide stimuli and clues on how to navigate the vast and varied world of geospatial data.
The following paragraphs are dedicated to some large types or families of data, tools and infrastructures that it would be important for PhD students to recognize at least in their purpose and specificity. The articulation of the different paragraphs is dictated by our intention to provide a first broad classification of the vast world of urban and territorial data. This classification, which cannot be exhaustive, is fundamentally based on the type of sources, scales, formats and work environments. Each paragraph tries roughly to return definitions, actors involved in the processes of innovation and application, methods of functioning, aims and possible recipients. With reference to the latter, in some cases, any measures to be adopted for each case will be reported. In general, this contribution constitutes a synthesis effort that we certainly consider useful, if not even preparatory, to the conduct of empirical research activities dictated by the methodological approach of the School of the “Souths of the World 2019”. What is gathered in this contribution is in fact the prerequisite for more detailed explorations to be hopefully constructed around one or more of the ten urban variables identified by the aforementioned methodological framework: density; diversity; dimension; porosity; social and geographical mobility; informality, poverty, informal economy; social norms and commons; governance and social capital, rationality and openness; housing and ecology.
- Institutional geoportals and Open Data
In the last two decades, technologies related to spatialization and geo-referencing of data have made great strides. Not only private companies and institutions specialized in this sector have developed information systems and web platforms dedicated to the systematization and querying of geospatial data. Also public institutions, at different levels, have designed and implemented innovative platforms for managing and sharing their official data, starting with the registry and census records referring to a variety of administrative and functional geographies. This fact has produced positive impact on the academic research initiatives since official statistics can and must still represent a fundamental resource for urban research. Every institutional effort to detect and harmonize census and registry statistics, to make them accessible, searchable, downloadable, continues to be valuable even in an age in which big data seems to annihilate effectiveness, in describing ever more changeable and complex contemporary phenomena, of databases, geo-statistical repositories and more traditional atlases. The main concerns, as is known, are on the one hand the gradual aging of information, on the other their space-time comparability since the historical detection thresholds do not always coincide with data coming from other innovative sources in more rapid updating. Other kind of problems derive from the anchoring of official institutional data to administrative boundaries that are less and less able to reflect the socio-spatial phenomena in progress.
With reference to institutional data, it is important to note that in recent years interesting initiatives have been developed for the construction and management of homogeneous databases on a global or continental level positively affecting the knowledge of the Global South countries. Some operations specifically addressed to these countries have led to Open Data portals managed by or in cooperation with some international institutions such as the World Bank, the United Nations and the OECD. Since the first government policies on Open Data appeared in 2009, many improvements have been made and today more than almost 50 developed and developing countries have launched their Open Data initiatives at national, subnational and city levels (World Bank, Open Government Data Toolkit). A very detailed overview designed to conduct comparative analyses on the spread of institutional Open Data at a global level is offered by The Open Data Barometer (ODB), a portal produced by the World Wide Web Foundation with the support of the Omidyar Network. The ODB aims «to uncover the true prevalence and impact of open data initiatives around the world» combining «contextual data, technical assessments and secondary indicators» [fig. 4].
Fig. 4 – Open Data Barometer: chart illustrating the state of the Open Data implementation in India
The World Bank open data portal is also worth mentioning as it systematically collects thousands of datasets from countries around the world, also concerning microdata. On the microdata front, the NADA case is particularly relevant since it is an open source microdata cataloguing system developed by the World Bank Group that “serves as a portal for researchers to browse, search, compare, apply for access, and download relevant census or survey datasets, questionnaires, reports and other information”.
If we exclude for a moment the strictly geospatial data, a very interesting relationship to explore and to spend a few words on is that between official data and statistics and informal phenomena which tend, for obvious reasons, to escape from official surveys. Since informality (urban and not only) is a distinctive trait for many realities in the southern hemisphere, it may be useful to clarify that some countries are attempting to obviate its physiological statistical fleetingness. As the World Bank makes clear, “in the principle, the informal sector should be included in national statistics”, however the governments of some countries have long started to include in their surveys also data referable to the informal sector. The World Bank also mentions the virtuous example of the United Nations Economic Commission for Europe (UNECE) that has built an inventory of practices of its 29 member countries that measures “non-observed economic activities (underground, illegal, informal or undertaken by households for their final use)”. The OECD also conducted a similar operation in the past (2002) by publishing a real handbook entitled Measuring the Non-Observed Economy. Among the virtuous experiences on this topic we find also the General Data Dissemination System published by the International Monetary Fund (IMF), as reported as well on the World Bank web site.
In addition to the cases described above, other types of not merely statistical geoportals are offered by different (not only institutional) subjects. Unlike the official statistics which often, especially in the countries of the southern hemisphere, make use of obsolete and therefore rigid portals and information technology, this second case is characterized by being accessible and consultable through new generation websites and platforms often with dedicated software and Web GIS clients. Worldwide, the first actual geoportals (web portal used to access geospatial information and geographic services) were developed and launched in the 1990s by US governments. Today there is a proliferation of geoportals for sharing of geographic information based on region or theme. Even when developed within US or Europe, new geoportals and data management standards produce positive impacts on other countries. As examples we can consider the ESRI ArcGiS Hub dedicated to Africa [fig. 5] (geospatial tools data and training, free for users working on Africa geospatial challenges) and the EU-JRC worldwide observatories. Another representative of this family is the Africapolis.org portal produced by the OECD Sahel and West Africa Club. It is the «only comprehensive and standardised geospatial database on cities and urbanisation dynamics in Africa. Combining demographic sources, satellite and aerial imagery and other cartographic sources, it is designed to enable comparative and long-term analyses of urban dynamics» [fig. 6].
Fig. 5 – A screenshot from the Africa GeoPortal (ESRI ArcGIS Hub)
Fig. 6 – A screenshot from Africapolis.org (OECD Sahel and West Africa Club)
A great innovation in the field of geospatial data consultation and OpeGIS was the introduction of the so-called Consultation Service, in particular the Web Map Service (WMS) and the Web Feature Service (WFS). This type of web services has allowed forms of standardization and intersection between different geographic systems offering the possibility to directly transfer, access, analyse and process spatial data coming from different sources. According to the European INSPIRE guidelines, a Consultation Service should allow at least to display, navigate, vary the display scale and portion, overlap datasets that can be consulted, and to display the information contained in the legends and any relevant content of the metadata (Directive 2007/2/EC). Also this type of web services developed in Europe are gradually spreading to other parts of the world.
- Photo-cartographic mosaics
The term “mosaic” in the field of geospatial data refers to assemblages of single or multiple images and cartographies from different sources. These can be the result of systematic activities (automated or manual) or more sporadic and circumscribed technical, scientific, cultural or media operations.
In this section we deal in particular with some fundamental photo-cartographic mosaics with global or at least supranational coverage, produced by highly qualified and specialized subjects. In addition to the more or less free initiatives mentioned in the following paragraph – in certain cases, it must be said, lacking in the methodological rigor or exhaustive information about the same methodologies used – there are also types of photo-cartographic assemblages that are the work of specialized subjects who are responsible for the construction and management of global mosaics used by millions of people all around the world.
Photo-cartographic mosaics can cover different families of information, different themes and different types of data. This means that even the primary sources from which the materials subject to mosaic are derived can have different nature and sources. In most cases purely cartographic mosaics tend to recompose, homogenize and make usable (at least accessible) fragmented information layers at national or sub-national level referring to land cover (natural, agricultural, urban), infrastructure and related flows, presence of population (mainly resident population), boundaries (administrative and otherwise), hydro-geomorphological elements and phenomena, environmental, climatic, epidemic phenomena etc. The level of definition can vary depending on the type of information and the origin of the data, but it is not always possible to push up to the urban and local level. With reference to the theme of “soil”, for example, it seems useful to point out the great work by ISRIC (International Soil Reference and Information Centre), an independent foundation whose mission is to serve the international community through the production, gathering and compilation of reliable and freely-available relevant soil information to address global environmental and social challenges. The SoilGrids.org project, powered by ISRIC, seems exemplary with respect to the specific issue discussed in this section [fig. 7].
Fig. 7 – A screenshot from SoilGrids.org (powered by ISRIC)
Besides the purely cartographic mosaics, photo satellite mosaics are available. These are extremely important because they are often at the origin – through technically complex remote-sensing and photo-interpretation processes – of thematic cartographies, in particular those on land covers, soil features and soil temperatures. In fact, thanks to the radiometer and thermal infrared sensor on board of the last generation satellites, such as Sentinel-3 (ESA) and Landsat-8 (NASA-USGS), it is possible “to detect long wavelengths of light emitted by the Earth whose intensity depends on surface temperature”.
Photo-cartographic mosaics play an important role in research for several reasons. The first reason is related to their use as maps of first (in remote) exploration and knowledge of the geographical contexts under study. The second is related to their use as basic layers (cartographic backgrounds) for different sectorial analyses that need to be spatialized, even for those who lack specific cartographic skills. Other equally important reasons concern the “mediation” effort, also linguistic, between different cultural contexts, as well as the effort of homogenization and construction of dedicated platforms that allow their use to any type of user. Moreover, it is evident that photo-cartographic mosaics are particularly useful where research interests and questions require comparative approaches and methodologies in the study of cities and regions distant from each other. In addition to geographical comparisons, thanks to the high technical skills and technological endowments of the actors involved, these mosaics allow to obtain information referred to contexts that are otherwise under-represented or lacking visibility. In this sense, the efforts of voluntary consortia aimed at developing international standards for the management of geospatial data were of fundamental importance. That is the case of the Open Geospatial Consortium (OGC), an international organization comprising almost 500 companies, government agencies and universities which has developed “more than 30 standards for a variety of geospatial data types, including the KML format developed by Google and submitted to the OGC”.
In terms of geospatial mosaicking, Google Earth is probably the best known and most used case in various scientific and professional fields. It is in fact a system of satellite and topographic imagery mosaicisation made available through a specific software but also through a web version. A very useful function for several reasons, also very popular even if available in a non-homogeneous manner, is Google Street View. This tool allows users to make screen observations at ground level through panoramic views (360° horizontally and 160º vertically) [fig. 8].
Fig. 8 – In blue, the geographical areas where the Google Street View function is available.
- Assembled maps and datasets
In recent years the potentials and the possibilities offered by technology have become the basis for many mapping and information sharing projects globally. At the urban scale, information is available almost all over the planet for what concerns socio-economic data, but also for environmental and demographic ones. Therefore, the technologies and the availability of information – not necessarily ready to be mapped – have led to the proliferation of digital mapping initiatives. The assembled data are those examples in which the promoters bring together in a usually virtual space various information that can be of two types (i) scattered information coming from different databases (for example house numbers, national population, etc.) that are globally combined (as for example, GeoNames); (ii) different information already present at a global level that are reworked with the construction of indicators between the different information layers (world population, urbanized area, etc.) realizing new information (population density, accessibility, etc.).
The subjects that promote this kind of actions are multiple but usually it is the result of the work of researchers, freelancers, private citizens or associations etc. The purposes are often different and range from research objectives combined with the desire of scholars to show and share information to the public up to reporting operations or more simply pure sharing of information. The objective of the section is to understand whether these types of data can be used in researches or as a tool to support the monitoring or the reporting of existing situations. For this purpose, four key factors that can guide the user in the search (and combination) of information sources have been investigated: reliability, open or closed dataset, technical skills needed, temporality and funds. These will be discussed further in the following examples.
The first case concerns the investigation of data reliability. Especially in situations where these data will become the basis for official projects it is necessary to explore their authority. The user must therefore be aware of how rigorous and correct those data are from the point of view of their construction-aggregation and the correspondence to the reality of the facts.
The first example is the Global map of travel time to cities to assess inequalities in accessibility in 2015 (Weiss et al., 2018) published on Nature during 2018. The aim of the research was to develop and validate a map that quantifies travel time to cities at a spatial resolution of one by one kilometre by integrating ten global scale surfaces and 13k high density urban centres. The results highlight disparities in accessibility relative to wealth as 50.9% of individuals living in low-income settings reside within an hour of a city compared to 90.7% of individuals in high-income settings [fig. 9].
Fig. 9 – Example of a research on the accessibility to cities
This is an assembled map that uses the technology of the European Community “Global Human Settlements Grid” together with the open data of OpenstreetMap and the Google Maps data concerning infrastructures. There is, therefore, a double mix both of data (population and infrastructures) and sources. The research consists of authoritative and truthful data as verified by both the researchers and the journal’s reviewers.
At the same time this research – as well as other cases i.e. Strava website or the ArcGis initiatives  – does not allow other subjects to reuse data and therefore this could be a limitation. In fact, as seen above, the paradigm of open data is fundamental to guarantee the diffusion of new studies and works related to the knowledge of places and political decisions.
Regarding the positive elements of re-use possibility, the case of data opening of GADM is important. The initiative started within the academic environment – at the University of Berkeley – as a database of the location of the world’s administrative areas. Boundaries in this database include States, regions, departments, municipalities etc. and cover every country in the world [Fig. 10]. Visitors to the GADM website can download administrative boundaries for individual Nations or they can download administrative boundaries for the entire world. There are other similar websites like Natural Earth or Contour Map Generator and many others that are created following the open data paradigm.
Fig. 10 – Example of the GADM database (Brazil)
Source: author’s elaboration
Another crucial example is The Armed Conflict Location & Event Data Project (ACLED). It is “a disaggregated data collection, analysis and crisis mapping project”. ACLED records the information of all reported political violence and protest events across the world with the aim to “capture the forms, actors, dates, and locations of political violence and protest as it occurs across states” [Fig. 11]. All the data are available for free download and the website features a dashboard that allow some data analysis and interpolation.
Fig. 11 – Example of the ACLED online map
The objective of these works is not to provide an interpretation or analysis of the data by combining various databases or information, but to collect information regarding boundaries, or toponyms, or contour lines, or protests and fights from various sources or by data manipulation and to share information with the community allowing the creation of new analyses / studies.
Whether in the case of the travel time to cities it is the map, as a final result, that leads the user to understand the objective of the researchers, in these cases the objective is not the study of a phenomenon but the information sharing. To use the data, the user – as in many cases similar to these – should be an expert and know software and technologies that allow the usability of the datasets. This should be a part of a general reflection related to the importance of the user-friendly dataset release but at the same time it should help to understand how to train the user to increase their capacity to use the dataset. It is important in order to consolidate and expand a community that knows how to use, improve, update and increase the data.
For the last key factors, we use another global map – this time produced by a private organization – as an example of the “Global Forest Watch” [fig. 12]. It is an online platform providing data and tools for monitoring forests that was born in 1997 as a part of NGOs funding network.
Fig. 12 – Example of the Global Forest Watch map
This type of mapping has the purpose of monitoring and reporting some environmental aspects that in this case concern global forests and their development or disappearance. The positive element of this example is the importance of simplifying and restoring complex data (in this case, satellite images produced by various institutions). Compared to the first case, it is possible to interact with data and download some of them.
One of the main nodes of this type of database is their economic sustainability. This is a common theme for most online initiatives: their destiny in the medium-long term. In many cases, the websites are funded with the community or organization support (UN, European Union, etc.) for a limited amount of time and money. Therefore, the dilemma regarding what will happen in the future cannot be avoided. It is a crucial point because some of the (non-official) databases might disappear leaving a huge gap in the knowledge of the contexts.
In conclusion, it is useful to underline that these typologies of initiatives, with pros and cons previously described, are very important because they increase the information and the knowledge about the global phenomena grouping and spreading data otherwise difficult to recover. Several examples range from economic macro-data to the submarine infrastructures to the number of scientific publications of each state to the spread of social networks and to the population density. Clearly, this type of database is fundamental for those countries in the Souths of the world, which, sometimes, do not have internal databases able to provide precise information: for example, the activities of ACLED are useful and crucial to report and denounce the fights that usually are not monitored especially in those fragile areas.
The work of searching for alternative sources and data can really be fundamental for the studies and for the communities of those countries. It turns out therefore that these mixed examples are useful to underline the richness of information about the Souths of the world. Maybe, it could be interesting to create a portal to gather these websites or researches in order to have an easier starting point to understand our planet and to reuse the information produced over the years.
- Volunteered geographic information (VGI) as global data source
An overview on geospatial data available in different geographical contexts cannot avoid to treat some specific sources provided directly by users according to their personal interest, their willing, their involvement in local projects and communities.
In 2007 Goodchild introduced the broad concept of Volunteered geographic information (VGI) as a novel source of geographic data coming from collaborative mapping projects that represent the set of geographic information generated and shared by a community of users through a data infrastructure (Goodchild, 2007). The reason why people decide to map, how accurate are the results and how this user generated content can augment more conventional sources can be discussed, but there is no question that this is one of the biggest innovations in the world of data production in recent years.
The VGI represents an innovation in the panorama of geographic data especially as a potential tool for solving the problem of cartographic material production and update involving the citizens’ knowledge. This is important for the public bodies mostly when the official cartography is lacking (Haklay et al. 2014). The constantly modifiable nature of the information characterizes the VGI as a new concept of knowledge: a cartographic representation that puts the “absolute power of the map, which admits neither criticism nor correction” into crisis. (Farinelli, 2003, p. 37). More and more open data-VGI hybrid systems are proving to be the most effective enabling technology vectors for innovative methods of mapping and enhancement of fragile and abandoned areas. This depends on many different factors but, first of all, on the possibility of interpolating extremely diversified data families coming from sources closely linked to the territory: this allows to make visible parts of that kind of local embedded knowledge that is often hidden or partially forgotten. In other cases, the use of local information sources is able to detect elements of the cultural landscape that are not mapped only because they are no longer part of the collective memory or have ended up unused due to an inability to enhance the stratified and lesser-known weave of our territories. This specific topic will be discussed in the next chapter.
Among the main VGI projects aimed at producing maps or data at the global scale, the most prominent and useful for urban research is definitely Openstreetmap (OSM).
OSM is a collaborative project aimed at creating an “open source” and editable map of the world. The data is grouped into different features, described by a number of tags such as amenities, buildings, highways, shops, railway, natural and many others. The map is created and maintained by nearly 5 million registered users and more than 1 million map contributors in every country in the world, using free tools and software.
Moreover, it has active mapper communities in many locations and it provides free and flexible contribution mechanisms for data (useful for map provision, routing, planning, geo-visualization, point of interests (POI) search, etc.) (Senaratne et al., 2017).
For this reason, it is not easy to state at the global level how this source is good and reliable for mapping purposes but at the same time there are some clear evidences that OSM is constantly improving in all regions, that OSM is often as good as or even better than what is commercially available and that more and more governments, institutions and researchers (Arsanjani et al., 2015) increasingly use and contribute to OSM [fig. 13-14].
Fig. 13 – Openstreetmap / Google map comparison in September 2017
Fig. 14 – Example of Openrouteservice for disaster management. Openrouteservice is a project based on OSM for routing application on a global scale. Available at https://disaster.openrouteservice.org
Humanitarian OpenStreetMap Team (HOT) for example, is an international team dedicated to humanitarian action and community development through open mapping. Among the projects, promoted by HOT OSM, it is worth to cite Missing Maps, an open, collaborative project in which it is possible to map areas where humanitarian organisations are working, some initiatives aimed at mapping different cities around the world (Accra, Monrovia) and a collaboration between HOT OSM and Facebook for building and improving OSM coverage for Southern Asia countries by using Machine Learning technology.
In urban research, OSM can be very useful as a starting point for further analysis and elaboration because it is very well integrated with Open Source GIS software and with spatial databases. It’s anyhow important to verify the quality and completeness of VGI data in respect of the scale and requirements of the ongoing investigations.
- Counter-mapping and back: participatory mapping as empowerment process
The role of maps as tools to exert power has changed in the last decades thanks to VGI frameworks allowing anyone to place oneself on a map, getting visibility, fighting spatial abuses and claiming for rights. This grassroots political effort to contrast hegemonic uses of maps by dominant powers and to democratize mapmaking has been defined as “counter-mapping” and has opened the way to several experimentations in participatory mapping that involve or are developed by initiatives of local communities, incorporating local cultural knowledge and promoting meaningful access to information in context of emergency or critical invisibility.
The concept of counter-mapping was introduced by Nancy Peluso to describe mapping initiatives that indigenous people in Indonesia undertook to contest governmental land-use plans disregarding the customary ownership and uses of community forests (Peluso, 1995). Similar projects already existed before coinage of the term, but since then, the connection between fragile communities and the potential of GIS technologies has opened to several experimentations in terms of participatory mapping initiatives moved by the aim to “cartographically and politically represent marginalized groups in relation to governments” (Craig et al., 2002).
Harris and Hazen stress these political implications defining counter-mapping as “any effort that fundamentally questions the assumptions or biases of cartographic conventions, that challenges predominant power effects of mapping, or that engages in mapping in ways that upset power relations” (Harris and Hazen, 2005, p.115). And Sebastian Cobarrubias, discussing the term in the Encyclopedia of Geography (Warf, 2010) recalls how “countermapping refers to the use of cartographic tools and maps to correct or denounce injustice. It is usually carried out in opposition to maps or spatialities produced by powerful interests, be they from the state, the private sector, or elsewhere.”
The political role of counter-mapping is explicit and it’s often related to activism as an aware process of reclaiming rights with spatial implications, “a conceptual framework for understanding and creating geographic and political change in the post-Fordist economy” (Dalton and Mason-Deese, 2012).
Among the different counter-mapping methodologies and strategies, as already discussed by Peluso (1995), two main mapmaking processes have emerged in consideration of the promoter of the counter-mapping effort. The most popular model sees international organizations and NGOs supporting local communities in collaborative mapping initiatives, while it’s less common to have local NGOs and communities directly contracting the services of international experts to be trained in mapping. In both cases a counter-mapping initiative requires the match of locally owned knowledge and the contribution of exogenous skills for the sake of a common goal, under the umbrella of a shared set of values that are violated or disregarded by the dominant power.
In both cases, mapmaking is intended as a social process, evolving from basic mapping and data collection to very detailed and high quality analysis to build awareness and visibility on peculiar culturally rooted spatial features (rules, uses, tenures) in areas of limited statehood (Kovačič and Landine, 2014). Thus, the mapmaking process, beyond filling knowledge gaps, turns into a capacity development and empowering occasion, also promoting active citizenship.
Sub-Saharan Africa, due to the relevance of the urbanization phenomenon in combination both with high socio-political fragility and a widespread availability of personal digital devices, has provided in the last decade a fertile context for counter-mapping initiatives coping with the challenge to bring invisible informal urbanities and citizens on a map to foster inclusive and sustainable urban plans, policies and projects. In this context, the initiative of external actors advocating local communities has prevailed.
In this perspective, Map Kibera has been a ground-breaking experience. The project, started in 2009 by Erica Hagen and Mikel Maron, aimed at overcoming the lack of available maps and data about Kibera, one of the world’s most-known slums in Nairobi (Hagen, 2011). As Hagen points out, Kibera wasn’t really invisible at first glance, being one of the most famous slums worldwide and “saturated with international NGOs, community-based organizations, and faith-based groups. The problem was that none of the existing maps were shared with the public or used by Kibera’s residents”, left disempowered and excluded from the processes to cope with their own neighbourhood’s challenges.
The first phase of the project was dedicated to participatory GIS mapping involving groups of local volunteering citizens and uploading data to OpenStreetMap. Participants were trained, getting “new knowledge about the impact technology can have on a community”, and validated as “holders of important information rather than poorly educated slum dwellers”, thanks to their sharing of “intimate knowledge of the paths, businesses, and social relations of their own neighbourhood […] This continues to be a primary concept behind Map Kibera’s work, but it remains a challenge because such local knowledge is traditionally held in low regard” (Hagen, 2011). Few in Kibera had seen themselves on a map before and paper printouts of the map were posted in public spaces and distributed in the neighbourhood to share the results of the first phase; on paper maps, residents were stimulated to add further information, opening the way to the following phase.
The second phase was aimed at transforming the map “to become an information resource that was truly useful to the community”, developing “a model for a comprehensive, engaged community information project” (Hagen, 2011). Citizen reporting was considered an essential part of the acknowledgment process and gave birth to two other parallel projects: The Voice of Kibera (voiceofkibera.org), an online community information and news platform, and the Kibera News Network (kiberanewsnetwork.org), a citizen video team. Lately, Map Kibera was institutionalised by becoming a Kenyan-based Trust, while the founders gave birth to GroundTruth Initiative, established as a new media and technology consulting company specializing in community-based participatory technologies, especially mapping and citizen journalism, in poor and marginalized regions throughout the world [fig. 15].
Fig. 15 – Map Kibera. Making informal settlements visible through cartography and digital media narratives.
Building on the experience in Kibera, the project was scaled-up and extended to another informal settlement: Mathare, the second largest slum in Nairobi. In Mathare, the mapping effort was directly focused on community development and followed the model of open data and open source software combined with participatory techniques to build a platform of dialogue within and outside the community. In 2012 another ICT-based collective action named Spatial Collective tested a further step by pushing the use of ICT from information delivery to concrete action complementing State’s activity (as facilitating water delivery in case of shortage) (Kovacic and Lundine, 2014).
Building on these experiences, in 2011, GroundTruth Initiative kickoffed community mapping in Dar es Salaam starting from Tandale and later supporting Slumdwellers International in their work mapping Keko Machungwa. In each community a target issue was selected as a focus to work on through reporting/mapping; in Tandale, it was the building of a secondary school. By mapping all the local schools, citizens were able to demonstrate the long distances separating some children from the closest school, as relevant information to support claims for the building of a new local school. Furthermore, a widespread awareness on the neighbourhood features was developed and shared by the local community.
The project scaled up in 2015, when the initiative Dar Ramani Huria (Swahili for “Dar Open Map”) extended the field of action. The community-based mapping project got funded by the World Bank and involved university students and the local community to create highly accurate maps of the most flood-prone areas of the city, essential tools to develop culturally rooted patterns of metropolitan resilience (Ramani Huria, 2016). Community mapping techniques were used to engage with local leaders and teach community inhabitants free, open source data collection tools from their smartphones. The data collected are enabling people across all levels of society to improve flood mitigation plans and to raise awareness and resiliency to natural threats. Furthermore, contemporary Dar es Salaam finally appeared on a map [fig. 16].
Fig. 16 – Ramani Huria. Mapping Dar es Salaam informal settlements to improve urban resilience.
In the last years, several similar initiatives popped up, and got a crucial role even in contexts of emergency or crisis, investigating methodologies to deal with humanitarian action and community development through participatory or community-led open mapping initiatives. In particular, it’s worth to recall two examples. One is the involvement of local communities by Médecins Sans Frontières (MSF) in creating updated maps to face the Ebola outbreak in Sierra Leone (Nic Lochlainn et al, 2018), a technological update of what happened in 1854 London with Snow’s fight to cholera, combined with capacity building. The other is the collaborative project led by Humanitarian Open Street Map (HOT) to help clarifying the spatial impact of refugee populations on local services in Northern Uganda (West Nile Region) with the aim of supporting decision makers to overcome siloing, to focus on operational efficiency, and to draft better strategies and policies to address the challenges of the ongoing humanitarian crisis by empowering local communities (Allan, 2018, p. 4) [fig. 17].
Fig. 17 – Humanitarian Open Street Map training local and refugee communities in the West Nile Region, Uganda, to map basic infrastructure and social facilities, claiming for rights.
The progressive institutionalization of counter-mapping as a practice adopted even by international organizations implies the risk of losing the radical drive that generated it, but opens to further extensive empowerment implications overlapping data ecosystems to urban patterns of digital citizenship. The Open Cities Africa (https://opencitiesproject.org) set of initiatives, supported by the World Bank, is a relevant example of this tendency. The project is carried out in 11 cities in Sub-Saharan Africa to engage local government, civil society, and the private sector to develop information infrastructures to build urban resilience by a collaborative approach [fig. 18].
Fig. 18 – Map of Zanzibar City showing the impact of participatory mapping initiatives in the last decade (https://opencitiesproject.org)
All the above-mentioned examples, representative of many more, consider counter-mapping as a socio-spatial platform for tailoring planning and design initiatives to communities’ needs and priorities in a more precise way, thanks to the understanding of culturally rooted patterns of value.
At the same time, when analysing them, few criticalities emerge, to be considered while dealing with counter-mapping. First, it’s relevant to stress how getting a place on the map means securing a place in the existing political framework, with relevant rights and duties, including the possibility (or right) to claim rights. This is not always an easy choice. Where political conditions are particularly critical, invisibility could still be preferred (Frigerio and Elgendy, 2019). Second, data validation could be an issue, as the processes don’t always imply specific verification methodologies and self-verification patterns can be ineffective. Third, the perspective of counter-mapping initiatives could sometimes be excessively limited to certain fragile categories or specific issues, lacking an overall synergy with broader urban phenomena. Fourth and last, the effectiveness of the initiatives and their legacy is still an issue to be further investigated. The cartographic legacy is clear, with most of the collected data contributing to Open Street Map or other open-source databases, but the socio-cultural legacy is difficult to evaluate and monitor.
- Media & telecommunication data and statistics owned by multinational companies
In recent years more and more new sources of data, mainly based on media and telecommunication data, have become available for urban and regional research. Thanks to spatial and temporal resolution, such data showed a great potential for understanding urban transformations, for analysing and mapping spatial patterns of activities within the cities. Such information can hardly be gained through conventional data. The census data output is usually coarse in resolution (e.g. local areas or counties rather than individuals or households). Moreover, the methods used to generate them are quite inflexible (for example, once a census is being implemented it is impossible to add/remove questions).
At the same time, it is not easy, if not impossible, to make general considerations on the quality and on the updating of the censuses at a global scale since the Census is conducted at the national level. For this reason, Census data quality and completeness must be evaluated case by case and depend on survey and estimate techniques, budget, competences, technical skills just to cite some issues.
On the other side, in urban research, the recognition of the “right” geographical scale for observing urban phenomena is not always easy. The re-scaling of data sources requires more flexible data and tools able to intercept urban phenomena in their correct spatial dimension. It clashes with the traditional data collection, because urban and regional data are normally available at the level of statistical subdivisions that correspond to municipal and administrative domains and not to the geographic dimension of processes and urban transformations. For this reason, in the last ten years, dozens of scholars searched for new data sources able to overcome some limits of conventional data (Blondel et al., 2015).
The idea is that mobile devices with location information leave digital traces when used by users. This implies to consider the phone traffic data as the effect of behaviours and individual habits that become indirect information on the characteristics of the territory and, somehow, an intrinsic feature of the same, that changes in time. The widespread use of mobile phone devices guarantees that the potential information available is huge and distributed among all the countries of the world.
ITU, the United Nations specialized agency for information and communication technologies (ICTs), estimates that at the end of 2018, 51.2 per cent of the global population, or 3.9 billion people, will be using the Internet. According to ITU, the growth in mobile cellular subscriptions in the last five years was driven by countries in Asia-Pacific and Africa regions. Growth was minor in the Americas and the Commonwealth of Independent States (CIS) region while a decline was observed in Europe and the Arab States. For this reason, this topic appears to be relevant within the context of this contribution aimed at presenting and discussing the main sources of data for the Souths of the world countries.
Media and communication data, and among them, mobile phone data appear to have great potential in urban analysis and planning, for recognition and identification of urban practices occurring in time and space. These phenomena are difficult to recognize through conventional data sources since they are rarely updated and since they are not able to intercept phenomena which change over time such as typically, mobility or the temporary presence of people in certain parts of the city, or the density of uses of territories or informal activities. Recent years have seen a growing debate on evaluation of the potential contribution of new sources of data, based on information collected anonymously by users, to official statistics.
In particular, the main question is the definition of methods able to integrate them with conventional data sources to overcome the limitations of conventional data in describing and measuring phenomena occurring in urban spaces.
Among these urban phenomena, mobility in its spatial and temporal articulation appears to be one of the main issues that call for the identification of new sources of data and methodologies able to describe it (Pucci et al., 2015).
Media and telecommunication data have a very fine spatial and temporal resolution and are very flexible. It is therefore feasible to analyse customized areas depending on the aims of the research (urban blocks, linear infrastructures, etc.). The precise spatial accuracy is therefore one relevant aspect that creates greater possibilities for detailed research.
Recent years have seen a growing debate on the potential contribution of new sources of data, based on information collected anonymously by users, to official statistics. The main issue relates to defining methods that can integrate new data sources with conventional data sources to overcome the limitations of conventional data in describing and measuring the phenomena that occur in urban spaces.
On the other hand, the real availability of mobile phone data is a relevant issue because of the huge fragmentation of providers in world countries and their lack of willingness to cooperate for public interest purposes such as an improved understanding of territorial development. The identification of conditions for the acquisition of private data by public institutions is a topic that needs to be fully addressed to define how this data source can contribute to a near real-time understanding of urban spatial processes [fig. 19].
Fig. 19 – Above normal flows from Kathmandu to other districts, as of
19 August 2015 on the basis of mobile phone data provided by Ncell (https://www.worldpop.org/region/nepal)
The original raw data are acquired by the network, processed directly by the company and provided to the scientific community in different formats, at different spatial and temporal resolutions and without an established standard for privacy issues, which is a dimension regulated by national laws.
Some relevant initiatives have been undertaken in order to expand the use of new sources of data for development and to improve data awareness in the context of the Souths of the world countries [fig. 20].
Fig. 20 – Mobility patterns and connectivity in West Africa (Wesolosky et al., 2014)
One example is United Nations Global Pulse which is a flagship initiative of the United Nations Secretary-General on big data. Big data, in its vision, is harnessed safely and responsibly as a public good. Global Pulse has worked on several research projects in collaboration with public and private partners for example on the use of mobile phone CDR for understanding refugee integration or for estimating socioeconomic indicators.
This concept is also promoted by several organizations and tech or telecommunication giants with ongoing programs and activities developed in the context of data for social good and international development initiatives. An interesting starting point for further analysis is a collection of projects and experiences based on the use of data provided mainly by private companies within the Data Collaboratives initiative. Collaboratives are a new form of collaboration, beyond the public-private partnership model, in which participants from different sectors exchange their data to create public value.
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 This paper is the outcome of a joint effort by the four authors. However, F. Curci (firstname.lastname@example.org) took primary responsibility for the introduction and wrote sections 1, 2 and 3; S. Saloriani (email@example.com) wrote section 4; F. Manfredini (firstname.lastname@example.org) and A. Frigerio (email@example.com) took primary responsibility for section 5; A. Frigerio wrote section 6; F. Manfredini wrote section 7.
 Paolo Perulli, “Alla ricerca del Sud Globale”, PhD Seminar held on 30th January 2019 at DiARC, University of Naples “Federico II”.
 OpenStreetMap (OSM), Wikimapia, Google Map Maker, Map Insight are some examples of Map-based VGI.
 For example, PostGIS is a spatial database based on the PostgreSQL object-relational database.
 The United Nations Statistics Division issues standards and methods to assist national statistical authorities and other producers of official statistics in planning and carrying out successful population and housing censuses.