23 July 2001
Symposium on Global Review of 2000 Round of
Population and Housing Censuses:
Mid-Decade Assessment and Future Prospects
Department of Economic and Social Affairs
United Nations Secretariat
New York, 7-10 August 2001
Census Mapping In Ethiopia*
1. Population and housing censuses can be conducted using any of the following methods:
· The group assembly method,
· The direct interview or the canvasser method, and
· The self-response method.
2. During the first attempt to conduct a population census in Ethiopia in September 1974, it was planned to have the urban areas covered entirely through the direct interview method. On the other hand, in the rural areas, where transport and communications were major problems, where the terrain is rough and difficult, and where more than 90 per cent of the country’s population lived, the group assembly approach was to be administered. In the group assembly method, all the heads of the households in a locality were obliged to assemble in one area and were required to supply limited information about all the members of their household. Moreover, for collecting detailed demographic data, a sample of 5 per cent of the localities were expected to be covered by the direct interview method conducted through house-to-house calls.
3. In a pilot census conducted in February 1974, both the group assembly method and the direct interview method were applied in three weredas (districts) in rural areas located in different parts of the country. The data collected using the two methods were compiled and compared; an underenumeration of about 20 per cent was found for the group assembly method compared with the population figure obtained by the direct interview method. Based on the lessons learned from the 1974 pilot census, it was decided to cover the entire population using direct interviews by making house-to-house calls.
4. Accordingly, in the 1984 and 1994 national population and housing censuses the direct interview method was used in the enumeration operation. The self-response method, where households or persons are supplied with blank questionnaires which they fill in and submit to the nearest census office, requires a highly educated population and could not be used under Ethiopian conditions either at that time or in the near future. However, the self-response method was used to enumerate foreign residents in the 1994 census. For this purpose a self-responding questionnaire was prepared in English and was handed over to the various embassies and homes of foreign residents by census supervisors. The filled-in census questionnaires were collected by the supervisors after a day or two. This approach helped to solve the language problem in enumerating foreign residents.
5. This paper deals with mapping activities in the national population and housing census carried out in 1994; it gives a brief note on mapping activities for the next national population and housing census planned to be conducted in the year 2004, and it ends with some conclusions and recommendations.
6. To conduct a census through direct interviews, it is essential to delineate the country into enumeration areas (EAs) in order to ensure that there is no duplication or omission of persons or households at the time of enumeration. The delineation of EAs also helps to fulfil the following functions:
· Assess the size of the manpower, questionnaires and other equipment required for the census;
· Provide comparable workloads to the enumerators;
· Ensure that the census is completed in the specified time;
· Follow up on the quality of the data collected (four to five EAs are designated as a supervision area (SA), and a supervisor is assigned to follow up on the quality of the data collected by the enumerators); and
· Provide a statistical frame for future socio-economic and demographic surveys.
7. The first stage in the process of the 1994 census map work consisted of collecting all the maps that were available for the rural areas and the urban centres. These maps were used as the base on which the census maps were prepared. The major maps for the purpose of census mapping that were available at the Ethiopian Mapping Authority for most parts of the rural areas were large-scale maps (1:50,000 or 1:250,000) and medium-scale maps for urban areas (1:5,000 or 1:10,000) of the country.
8. Ethiopia has a land area of 1,150,516 square kilometres. The country is divided into nine regions and two administrative councils. The regions or the administrative councils are further subdivided into 71 zones and 546 weredas (Ethiopia, CSA, 1998). The rural areas of the weredas are made up of Peasants’ Associations (kebeles) numbering 21,149, while the urban areas are made up of Urban Dwellers Associations (kebeles) numbering 1,656. The boundaries of all regions and most zones were changed between the 1984 and 1994 census, making comparisons over time at the subnational level very difficult. The administrative boundaries of many zones and most weredas in Ethiopia have changed since the 1994 census fieldwork as well.
9. The country also has a very rough terrain and most areas are inaccessible by motor vehicles. Most of the roads are dry-weather roads and can be used only during certain months of the year. All these indicate the difficulty involved in the delineation of the entire country into enumeration and supervision areas.
10. In the 1994 census mapping work, enumeration areas were constructed by tracing an area which contains a certain number of households or housing units on the base map. For this purpose, it is necessary to go from one housing unit to the next, listing all households and the number of persons in every household. A certain area is then delineated, such that it can easily be traced on the map, its boundaries can easily be described and identified during the census enumeration and it can be covered by one enumerator. This section briefly presents the process of preparing a manual for census mapping; recruitment and training of census mapping field staff; organization of field operations during census mapping; delineation of enumeration areas and formation of enumeration area maps; formation of supervision area maps; construction of wereda (district) maps; and other uses of census maps.
11. In undertaking census mapping work, it is essential to prepare a manual which will be used for the training of census mapping field staff and during the actual census mapping fieldwork. The manual for census mapping was prepared by a census mapping task force that was established by the Central Statistical Authority (CSA). The manual covered different aspects of census mapping work, such as geographic concepts, map reading, and the delineation of enumeration and supervision areas in rural and urban areas. Moreover, the manual covered the use of different maps for the formation of enumeration areas, as well as how to make a sketch map for a town when no base maps were available (Ethiopia, CSA, 1992).
12. The second phase of the census mapping work involved recruiting and training of census mapping fieldworkers. At the CSA, the census mapping supervisors were recruited from the regular staff of the office and were given 15 days of training. The fieldworkers (called geographical assistants) were recruited from youth with an educational background of grade 12 and above who had at least a passing grade in geography and English in the Ethiopian School Leaving Certificate Examination (ESLCE). The first batch of 1,000 geographical assistants was recruited in July 1992 and trained for eight weeks by the members of the census mapping task force. The training consisted of classroom instructions, classroom exercises and fieldwork. A few personnel from organizations other than the CSA also participated in the training of the geographical assistants. In addition, the census mapping supervisors later took part in the training of the geographical assistants. More geographical assistants were later recruited, trained and deployed in the operation so that by July 1993 there were around 2,000 census mapping fieldworkers in the field. It took about 18 months to complete the census cartographic work.
13. The existence of small administrative units like the peasants’ associations (kebeles) in the rural areas and the urban dwellers’ associations (kebeles) in the urban areas, greatly facilitated the census mapping work. This was because these kebeles had distinct boundaries which are well recognized. The officials in charge of these kebeles also substantially helped the cartographic work by providing consultations, publicity, transportation, lodging and other facilities to the geographical assistants and their supervisors.
14. During the census mapping fieldwork, the geographical assistants were organized into teams. Each team consisted of eight geographical assistants, two technical supervisors, one administrative supervisor, a driver, a cook and a camp guard. Each team was provided with a 10-seat four-wheel-drive vehicle; a tent for every two members of the team; and a mattress, a folding cot and a sleeping bag for every member of the team. The team was also provided with the necessary kitchen utensils—silverware, plates, cups and so forth.
15. During the census mapping field operation, the team stayed in a camp that was centrally located for their operation. Thus, the team proceeded to a wereda (district) and approached the wereda administration and briefed the officials on the objectives of their presence and the need for the support of the administration officials of the wereda as well as the kebeles in the rural or the urban areas. With the cooperation of the wereda officials, the team identified the wereda boundaries and collected the list of the kebeles and the names of chairpersons of the kebeles from the wereda office. The team also obtained a letter to the chairpersons explaining the objectives of the census mapping and the need to provide the team with administrative support in carrying out the census mapping in their respective kebeles.
16. Accordingly, at the outset the team selected a central location in one part of the wereda, where it established its camp and covered the kebeles in the rural or the urban areas within walking distance from the camp. When the team completed the census mapping in a location, they moved their camp to another location, where they carried out the census mapping for the rural or the urban kebeles around the new camp. This process of relocating the camp continued until the team completed the census mapping in the wereda; then the team moved to a new wereda to launch similar mapping activities.
17. The kebeles in rural areas were delineated into one enumeration area or subdivided into two or more enumeration areas according to the size of the kebele in question. Enumeration areas were never allowed to cross the boundaries of a kebele. An enumeration area in the rural area was expected to contain from 150 to 200 households, depending on its terrain and density. If the terrain was difficult or the population settlement pattern was very dispersed, the enumeration area held around 150 households, whereas if the terrain was good and if the population settlement pattern was not dispersed, it contained up to 200 households. In the urban areas, the kebeles were divided into enumeration areas which were entirely contained within the boundaries of the kebele. The enumeration areas in the urban areas also contained 150-200 housing units. Thus, for the 1994 population and housing census a total of 58,702 enumeration areas were delineated, of which 49,978 were in rural and 8,724 in urban areas.
18. Enumeration area maps contained the following information: region, zone, wereda, kefetegna (a higher kebele or groups of kebeles, in urban areas only), name of the kebele, name of the chairperson of the kebele, code number of the enumeration area, size of the enumeration area (in square kilometres), number of households in the enumeration area and number of housing units (in urban areas only). The EA maps also showed important landmarks, such as schools, health institutions, churches, mosques, roads and rivers, in the area and in its boundaries. Moreover, a description of the enumeration area, particularly of its boundaries, was also attached with the EA map.
19. About four to five adjacent enumeration areas were formed into one supervision area. During the census, one supervisor was assigned to one supervision area and had the responsibility of providing the enumerators with the necessary materials and facilities and in following up on the quality of their work. In the rural areas an average of five enumeration areas were grouped to form one supervision area, while in the urban areas around six enumeration areas were grouped to form one supervision area. Supervision areas were never allowed to cross the boundary of an urban kebele, a wereda or a kefetegna. Supervision area maps showed the boundaries of all the enumeration areas and the urban or the rural kebeles that it contained, the supervision area, and the code number of the supervision area. Accordingly, in the 1994 census mapping exercise, a total of 11,420 supervision areas were formed, of which 9,845 were in rural and 1,575 in urban areas.
20. Wereda (district) maps were also constructed during the census map work. The wereda maps indicated the number and also the boundaries of the kebeles in the wereda, the supervision areas, and the towns (the urban centres) in the wereda. The maps of the urban centres in a wereda were also constructed; these maps indicated the boundaries of the centre, the kebeles in the urban centre, the kebele boundaries and the EAs and SAs formed in the urban centre.
21. The EA, the SA and the wereda census maps are being used as a frame for drawing a sample in undertaking various socio-economic and demographic surveys. The maps are also being used for various administrative and socio-economic development activities by different government and non-government agencies, individual researchers and others.
22. The current population of Ethiopia, which is 65.3 million, is expected to reach 71.1 million by July 2004, 59.9 million in rural areas and 11.2 million in urban areas (Ethiopia, CSA, 1998). In the 1994 population and housing census the observed average household size was 4.8 persons. Assuming that this average household size will prevail at the time of the 2004 census map work, it implies that there will be about 15 million households. If an enumeration area constitutes about 150 households or housing units, the country will be delineated into about 100,000 enumeration and 20,000 supervision areas.
23. Since the 1994 census map work, the boundaries of the regions, zones, weredas and kebeles have changed considerably. More zones and weredas have been created and these changes are continuing. That is, weredas are being subdivided into either two or three weredas. Also two or three adjacent weredas are being combined into a single wereda. Moreover, adjacent kebeles in rural areas have been merged into one or a kebele has been subdivided into two or more. Hence, boundaries for most of the weredas and the kebeles in rural areas have to be demarcated in census mapping work for the next census. Accordingly, EA delineation is expected to be carried out for the entire country.
24. Census mapping operations require huge human and financial resources and are expected to take quite a long time, particularly if launched with limited field staff and logistics support. The 1994 census mapping operation required about one third of the entire census expenditure. It was carried out by deploying over 2,000 field staff and using over 100 four-wheel-drive vehicles, and it took about 24 months to complete the exercise in the settled parts of the country. This exercise did not cover the nomadic areas, which constituted about 10 per cent of the total population of the country at that time. In terms of area, the nomadic part of the country constituted not less than 30 per cent of the total land areas of the country.
25. The Central Statistical Authority is responsible for undertaking all the activities of the forthcoming decennial population and housing census planned to be conducted in 2004. However, currently the Authority is in the process of launching the first ever national agricultural sample census. The fieldwork (that is, the data collection) for this census is expected to start in September 2001, and this exercise will last until June 2002. Thus, most of the Authority’s professional as well as field staff, logistics support, field vehicles and so forth will be deployed in this operation. As a result, the Authority will not be in a position to undertake any major population census preparatory activities, particularly those that involve fieldwork, until June 2002. However, some preparatory activities for the planned census could be carried out between now and June 2002.
26. These preparatory activities, which include preparation of the census project document, have already started. A draft project document was prepared in collaboration with UNFPA-CST Addis Ababa in March 2001. In this project document, among others, emphasis was given to the census mapping exercise, including identification of maps and mapping equipment, human resources, training requirements, and the work plan for the census mapping exercise.
27. The procurement of Global Positioning System (GPS) equipment, computers, Geographic Information System (GIS) software and field vehicles and the training of the professional staff that will be involved in the planning and execution of the census mapping work could be carried out between now and June 2002. Moreover, activities such as the preparation and printing of census mapping documents such as the census mapping manual, household listing forms, and other forms associated with census mapping work could also be carried out during the above mentioned-period. Also, training of the trainers of the field staff could take place during this period.
28. The major census preparatory activity, which is census mapping, could be launched by recruiting the field staff during the first week of July 2002. This will be followed by training the field staff in different training stations ranging from 8 to 10 of the Authority’s 22 branch statistical offices all over the country. The training of the census mapping field staff will last for a period of six to seven weeks, and the actual mapping fieldwork, which is the delineation of EAs and SAs, will start during the first week of September 2002.
29. The census mapping exercises involve the identification of the boundaries of the kebeles in rural areas and in urban centres or towns. This activity is carried out by the mapping field staff with the assistance of the officials of the kebeles. These areas are demarcated on census base maps by acquiring georeferenced data with the help of the GPS receiver sets. The exercise will be followed up by listing of the households and housing units within each kebele. The listing activity is expected to be carried out on the basis of localities within the kebele. If the kebele in rural or urban areas has fewer than 150 households, it is left intact and becomes an enumeration area. However, if the number of households or the housing units within the kebele exceeds 150—and in most of the cases it does—the kebele area will be delineated into two or more enumeration areas and EA maps will be prepared. In the process of delineation of EAs, information on basic social services and infrastructural facilities will be collected. The location of these facilities will be recorded using GPS receivers.
30. In census mapping, if an urban centre does not have a base map—which is usually the case in small urban centres—a sketch map will be prepared for the urban centre (town) and will be delineated into two or more EAs, depending on the total number of households or housing units in the town.
31. The 2004 census enumeration is planned for mid-May 2004. Therefore, the census mapping activities should be completed by February 2004. This allows only about 18 months to complete the census mapping activities for the entire country, including the nomadic areas. Hence, enough field staff to undertake this exercise in about 18 months should be recruited and trained. Moreover, the necessary logistics and transportation facilities should be acquired to enable deployment of as many field staff as required for the exercise to be completed within the stipulated time.
32. The use of the latest state-of-the-art technology has the advantage of speeding up the operations, making it cost-effective, and improving the accuracy of census mapping. Hence, the Central Statistical Authority, in consultation with census mapping advisers of UNFPA-CST Harare and Addis Ababa, decided to make use of GPS receivers and GIS in its forthcoming census map work.
33. If this exercise is supported by such technology, it is estimated that a pair of mapping field staff could delineate and prepare eight EAs in a month. This implies that a team of eight mapping field staff supported by two technical supervisors and one administrative supervisor could delineate and be able to prepare up to 32 EA and five to six SA maps in a month.
34. As indicated above, the country’s population is expected to reach 71.1 million persons and about 15 million households by 2004. If we assume that an EA consists of a locality or localities with about 150 households or housing units, roughly about 100,000 EAs and 20,000 SAs will be demarcated in the country. Thus, in order to carry out this exercise in about 18 months, about 174 census mapping teams should be organized and deployed by the first week of September 2002. Accordingly, in terms of human resources requirements, the office has to recruit and train 1,408 census mapping field staff (with a minimum educational background of grade 12), 352 technical supervisors (regular CSA field staff who took part in the 1994 census mapping) and 176 administrative supervisors (regular CSA field supervisors).
35. Census mapping is one of the major census preparatory activities. It minimizes omission and/or duplication of households and/or persons at the time of the census enumeration. The enumeration and the supervision area maps also help the census office in determining the manpower and the census documents required for the census; help provide comparable workloads to the census enumerators and ensure that the census enumeration is completed in the specified time; help in the quality of census data collection; and provide a statistical frame for future socio-economic and demographic surveys. Considering these important uses of census mapping outputs, it is essential that mapping should be carried out with utmost care.
36. If the 2004 census is to use latest technology, it will be highly desirable to:
· Procure the required number of GPS receivers, including computers and software, that will enable the Authority to set up GIS capable of producing the necessary census maps at least by June 2002;
· Provide training to the Authority’s staff involved in the planning and execution of the census mapping in the use of GPS receivers and the use of computers and computer software in the application of GIS and consequently in producing the necessary EA, SA and district census maps. The training could be organized locally with the Ethiopian Mapping Authority (EMA) or with an overseas training institution offering courses in the application of GIS and related fields. This training should take place during the first quarter of 2002;
· Procure the required number of copies of different scale maps and available GIS data from EMA by January-February 2002; and
· Ensure that the census map work covers the nomadic areas of the country.
37. If CSA produces such maps, they should be shared with other users after the completion of the census enumeration and during the dissemination of the census results.
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_____ (2000). Handbook on Census Management for Population and Housing Censuses. Studies in Methods, Series F, No. 83. New York: United Nations.