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Organization
After the decision to carry out a census, it becomes essential to socialize it as a project. As such, a
number of committees have to be formed namely:
(i) The Central Census Committee whose role is to steer the operation. It consists of knowledgeable members who have authority to take decisions. They normally come from government institutions, data producers and data users.
(ii) The Technical Committee whose role is to deal with all technical aspects. It is responsible for decisions on recruitment and training of census staff, questionnaire design, sampling procedure, tabulation plan, field work, data processing, analysis and publication of reports.
(iii) Inter- Institutional Team comprising subject-matter specialists who are able to coordinate census logistics with crucial role of determining the demand structure of consumers.
Sampling Sampling is done for those establishments engaging 1 – 9 persons as indicated above.
Census Instruments
Two kinds of questionnaires are used for data collection, long and short questionnaires. The long
or the detailed questionnaire is used for establishments engaging ten or more persons and the short
questionnaire is used for establishments engaging one to nine persons.
Data collection Data collection is done through interview. An enumerator is supposed to visit all establishments involved in Industrial Census dealing with mining and quarrying, manufacturing, electricity, gas, steam and air conditioning supply, and water supply, sewerage, waste management and remediation activities. When the completed questionnaires are received from the regions, each questionnaire is registered by recording the establishment’s Identification number, ISIC Code, Region Code, district code and size code. Then the questionnaires are filed region-wise ready for data entry.
Manual editing, coding, data entry, validation and tabulation Editing and coding is done immediately after the arrival of questionnaires at the NBS headquarters. Data entry is done using personal computers to the designed data entry system. Data
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validation is done to detect outliers’ figures and miss-keying in of data by data entry operators. Tabulation is done using statistical packages.
5.3.3 Reference to applicable standard classifications All establishments are classified by ISIC Revision 4 codes by considering the main activity of the establishment.
5.4
PRODUCER PRICE INDEX (PPI)
Producer Price Index measures the average change over time in the prices received by selected
domestic producers for the production of their goods. A basket includes a list of selected
commodities of goods that are being priced on quarterly basis. The producer prices are collected
as at 15th of the mid-month of every quarter that is February, May, August and November for
Quarters (January-March), (April-June), (July-September) and (October-December) respectively
Weights and a Reference Period The index weights are based on gross output derived from the 2008 Annual Survey of Industrial Production. Currently, the PPI release reports the price indices with reference to March 2013, as the base period. It shows the producer price changes since March 2013 on three major sub-sectors of industry (Mining, Manufacturing, and Utilities).
5.4.1 Objectives and uses of the PPI
The survey aims at producing basic quarterly statistics on prices of major or selected
commodities according to International Monetary Fund Recommendations for Producer Price
Index compilation. The survey is intended to:
(i)
Collect quarterly producer price statistics on the industrial sector in the country;
(ii)
To identify the turning points of prices on industrial commodities at early stage;
(iii)
Obtain data for computing National Accounts estimates;
(iv)
Assess the current status of the industrial sector in the country;
(v)
Indices are used in economic policy making and forecasting future economic
performance in the industrial sector;
(vi)
Identify conditions that affect firm-level productivity and competitiveness; and
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5.4.2 Methodology of data production In the process of deriving the structure and weights, a top-down approach is adopted, the basket is selected and currently 2008 is used as a base in weights calculation. A top-down approach is adopted for the calculation of the weights in order to maximize the indirect representation of industries and items. A sample of establishments for inclusion in the price survey is then selected using cut-off sampling procedures. The price relatives of the selected commodities on each four digit level of ISIC is computed. The first level of aggregation is the class 4-digit ISIC; these indices are the un-weighted Elementary Aggregate (EA) and are being compiled using the Jevons geometric mean aggregation formula which refers to Geometric Mean of the price relatives. The Elementary Aggregates indices are then being progressively combined to higher levels within the index structure (i.e. Group 3-digit, 2-digit division and 1-digit Section levels of the ISIC, and then the all groups level) using the standard base-weighted Laspeyres formula. 5.4.3 Reference to applicable standard classifications Commodities Classification follows the International Standard Industrial Classification of All Economic Activities (ISIC) Rev.4.
5.5
CONSTRUCTION INDUSTRY SURVEY (CIS)
The construction industry is a sector of the economy that uses various resources to construct
physical, economic and social infrastructure necessary for socio-economic development.
Construction includes general construction and specialized construction activities for buildings
and civil engineering works, (UN, 2008). It includes new work, repair, additions and alterations,
the erection of pre-fabricated buildings or structures on the site and also construction of a
temporary nature.
General construction is the construction of entire dwellings, office buildings, stores and other public and utility buildings, farm buildings etc, or the construction of civil engineering works such as motorways, streets, bridges, tunnels, railways, airfields, harbours and other water projects, irrigation systems, sewerage systems, industrial facilities, pipelines and electric lines, sports facilities, etc. This work can be carried out on own account or on a fee or contract basis. Portions of the work and sometimes even the whole practical work can be sub-contracted out. A unit that
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carries the overall responsibility for a construction project is classified here. Also, included is the repair of buildings and engineering works.
Construction Industry is classified into the following divisions, (UN, 2008): Construction of Buildings (Division 41), Construction of Civil Engineering Works (Division 42), and Specialized Construction Activities (Division 43).
5.5.1 Objectives and uses of the CIS
General objective
The main objective of the Construction Industry Survey (CIS) is to measure the performance of
Construction and Distributive Trade Sectors
Specific Objectives
(i) To obtain information on the number and geographic distribution of construction establishments; (ii) To estimate the number of persons engaged in this sector; (iii) To get estimates of the contribution of the construction activities to Gross Domestic Product (GDP); and (iv) To obtain data that could be helpful in formulating socio-economic plans and programmes.
Uses of CIS Construction Industry Survey measures the performance of key indicators of the construction sectors of the economy. The information collected is used in the compilation of National Accounts aggregates such as Gross Domestic Product (GDP)
5.5.2 Methodology of Data Production
Methods and approaches The main research methods and approaches include organization; planning, design and concept paper preparation; piloting; refinement of survey instruments; up-dating sampling frame; sample design; recruitment and training of trainers (TOT); training of supervisors and enumerators; field survey; data processing and management; data editing and coding, data entry, validation,
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tabulation and analysis; main investigation variables and statistical indicators; statistical packages (CSPro, MS access, MS excel and MS word); data files and backup systems; report writing; national stakeholders workshop and dissemination/ publication.
Questionnaire Design The construction industry survey uses two questionnaires (small and large) for data collection. The small questionnaire (CIS 1 FORM A) covers establishments of contractors in classes 5 to 7 (with an average investment cost of less than 500 million shillings) and the large questionnaire (CIS 2 FORM B) covers establishments of contractors in classes 1 to 4 (with an average investment cost of more than 500 million shillings)
Sample design The classification of activities is based on the International Standard Industrial Classification (ISIC) Revision 4. In practice, complete coverage is impossible due to limited financial resources, hence the survey is done on a sample basis. In construction survey, all establishments in classes 1 – 4 are fully covered while those establishments in classes 5 – 7 are sampled. The sampling strategy ensures representation by class, size and classification of the economic activities at national level. The stratification in construction is based on the activity and class of the establishment.
Field Work Data is collected from the establishments through interviews. Managers of the respective establishments are visited by enumerators and asked to supply the required information.
Data Processing and Management Data processing centralized at NBS Head Office, starts one month after the commencement of fieldwork and continues concurrently with the field enumeration exercise. The data capture system is developed using CSPro and tables are produced through MS Access. Data processing is accomplished in two months.
Data editors are supposed to edit the questionnaires received from the regions by checking the correctness and fill-in the respective codes. Edited questionnaires are entered into the computer by data entry operators. On completion of data entry, the data are cleaned by the subject matter staff assisted by the IT staff and data verifiers for validation checks of the data variables.
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The main investigation variables used for checking consistence of data entered in the database are employment, labour cost, expenditures and receipts.
5.6
TANZANIA TOURISM SECTOR SURVEY
Tanzania Tourism Sector Survey is managed and implemented by five participating institutions
namely, the Bank of Tanzania (BOT), the National Bureau of Statistics (NBS), the Ministry of
Natural Resources and Tourism (MNRT), Immigration Department and Zanzibar Commission for
Tourism (ZCT). These institutions have been carrying out the International Visitors’ Exit Surveys
since 2001.
5.6.1 Objectives and uses of the Tourism Sector Survey
Tanzania Tourism Sector Survey intends to collect up-to-date tourist expenditure information for use in the ‘’Tourist Expenditure Model” developed in 2001. The Model was developed as a tool for estimation of international tourism receipts required in the compilation of National Accounts (NA) and Balance of Payments (BOP) statistics.
Use of the Tourism Sector Statistics These statistics are used by the public and the private sector for policy formulation and strategic business planning, respectively.
5.6.2 Methodology of data production Scope of the Survey The survey targets international visitors to Tanzania. A person is considered as an international visitor if he/she travels to a country other than that of his/her usual residence, and outside his/her usual environment for a period not exceeding twelve months and whose main purpose of visit is other than an activity remunerated from within the country visited.
Sample size The survey sample size is normally designed to capture about one percent of Tourists arrivals annually. In order to allow comparability, the sample size has remained constant over years.
Survey period
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The survey is usually conducted during the tourist peak season (July -September), in order to be able to capture most of Tourists’ characteristics. In that regard, a two-week survey is normally done during this peak season.
Coverage
Since the survey aims at obtaining data on inter alia, expenditure and length of stay, it is necessary
that it is carried out at departure points. The survey is normally conducted at eight major departure
points, namely Julius Nyerere International Airport (JNIA), Kilimanjaro International Airport
(KIA), Abeid Amani Karume International Airport (AAKIA), Namanga (NAM), Tunduma
(TUN), Mtukula (MTK), Horohoro (HOR) and Manyovu (MANY) border points.
The Questionnaire
The questionnaire is designed to ensure that, the questions asked are in line with users’ data needs.
The information collected is useful for tourism promotion and macroeconomic policy formulation.
A single questionnaire is used to gather information on International Visitors` Exit Survey.
The content of the questionnaire is based on the previous years’ questionnaires with slight
modifications. The questionnaire comprises of four main parts, namely:-
(i)
Visitor profiles - (nationality, country of residence, age group, purposes of visit,
type of tourism activity and source of information about Tanzania),
(ii)
Travel behavior - tour arrangement (package/non-package), items in the package
and number of nights spent.
(iii)
Expenditure patterns - tourists’ earnings ascribed to Tanzania. In addition, the
questions probed for details on the amount of money spent in Tanzania, mode of
payment as well as comparison of cost with other African countries.
(iv)
Visitor comments - whether the visit is the first time or not and; information about
areas that impressed the visitors and those which need improvement.
Data Processing The processing of the International Visitors` Exit Survey data begins after completion of the fieldwork. Data processing involves manual editing, coding of open-ended questions, data entry and editing of computer-identified errors. Data entry and editing are accomplished using the ORACLE11g database and web-based application.