TUV_2010_HIES_v01_M
Household Income and Expenditure 2010
Name | Country code |
---|---|
Tuvalu | TUV |
Income/Expenditure/Household Survey [hh/ies]
The "Household Income and Expenditure Survey (HIES)" is the largest national survey carried out by the Central Statistics Division (CSD) of the Ministry of Finance, Economic Planning and Industries in accordance with international standards. The first survey was carried out in 1994, the second in 2005, with this being the third. It provides statistical information on income and expenditure patterns of households in Tuvalu.The first objective is the update of the CPI. Poverty analysis are based on this survey and many MDG indicators can be calculated from this survey.
The main objectives of the survey were:
Sample survey data [ssd]
Version 01: Raw data, available for internal use.
2010-10
HOUSEHOLD FORM
INDIVIDUAL FORM
DIARY
National, including Funafuti and Outer islands
All the private household are included in the sampling frame. In each household selected, the current resident are surveyed, and people who are usual resident but are currently away (work, health, holydays reasons, or border student for example.
If the household had been residing in Tuvalu for less than one year:
Name | Affiliation |
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Central Statistics Division | Ministry of Finance and Economic Development |
Name | Affiliation | Role |
---|---|---|
Chris Ryan | Secretariat of the Pacific Community | Technical assistance - questionnare design, data proccessing and analysis |
Bertrand Buffiere | Secretariat of the Pacific Community | Technical assistance - questionnare design, data proccessing and analysis |
Name | Role |
---|---|
Asiatic Bank of Development | Funding |
United Nations Develpment Program | Funding |
Republic of China | Funding |
Government of Tuvalu | Funding |
It was decided that 33% (one third) sample was sufficient to achieve suitable levels of accuracy for key estimates in the survey. So the sample selection was spread proportionally across all the island except Niulakita as it was considered too small.
For selection purposes, each island was treated as a separate stratum and independent samples were selected from each. The strategy used was to list each dwelling on the island by their geographical position and run a systematic skip through the list to achieve the 33% sample. This approach assured that the sample would be spread out across each island as much as possible and thus more representative.
For details please refer to Table 1.1 of the Report.
Only the island of Niulakita was not included in the sampling frame, considered too small.
The final response rates for the survey was very pleasing with an average rate of 97 per cent across all islands selected. The response rates were derived by dividing the number of fully responding households by the number of selected households in scope of the survey which weren't vacant.
For details please refer to Table 1.2 of the Report.
The sample weight were calculated for each island (8 differents weight).
For the island i, the weight of the household (W) was calculated as shown:
Wi = Total number of household in island i / number of valid questionnaire in the island i
There were three main survey forms used to collect data for the survey. Each question are writen in English and translated in Tuvaluan on the same version of the questionnaire. The questionnaires were designed based on the 2004 survey questionnaire.
HOUSEHOLD FORM
INDIVIDUAL FORM
DIARY (one diary per week, on a 2 weeks period, 2 diaries per household were required)
Questionnaire Design Flaws
Questionnaire design flaws address any problems with the way questions were worded which will result in an incorrect answer provided by the respondent. Despite every effort to minimize this problem during the design of the respective survey questionnaires and the diaries, problems were still identified during the analysis of the data. Some examples are provided below:
Gifts, Remittances & Donations
Collecting information on the following:
Defining Remittances
Because people have different interpretations of what constitutes remittances, the questionnaire needs to be very clear as to how this concept is defined in the survey. Unfortunately this wasn?t explained clearly enough so it was difficult to distinguish between a remittance, which should be of a more regular nature, and a one-off monetary gift which was transferred between two households.
Business Expenses Still Recorded
The aim of the survey is to measure "household" expenditure, and as such, any expenditure made by a household for an item or service which was primarily used for a business activity should be excluded. It was not always clear in the questionnaire that this was the case, and as such some business expenses were included. Efforts were made during data cleaning to remove any such business expenses which would impact significantly on survey results.
Purchased goods given away as a gift
When a household makes a gift donation of an item it has purchased, this is recorded in section 5 of the diary. Unfortunately it was difficult to know how to treat these items as it was not clear as to whether this item had been recorded already in section 1 of the diary which covers purchases. The decision was made to exclude all information of gifts given which were considered to be purchases, as these items were assumed to have already been recorded already in section 1. Ideally these items should be treated as a purchased gift given away, which in turn is not household consumption expenditure, but this was not possible.
Some key items missed in the Questionnaire
Although not a big issue, some key expenditure items were omitted from the questionnaire when it would have been best to collect them via this schedule. A key example being electric fans which many households in Tuvalu own.
Start | End |
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2010-03-03 | 2010-06-12 |
Name | Affiliation |
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Central Statistics Office | Ministry of Finance and Economic Development |
The fieldwork was carried out by 42 specially selected interviewers and 13 supervisors, supported by 2 trainers and 4 staff of the Statistics Department who acted as supervisors.
The Household Income and Expenditure Survey 2010 was carried out by the Tuvalu Central Statistics Division over a period of 3 ½ months throughout the first half of 2010, covering eight islands of Tuvalu. The survey collected information from 541 households from these islands, with the only island excluded from scope of the survey being Niulakita.
Although "Dwellings" were selected in the sample, information was collected from "Households". A dwelling was considered to have more than one household if there more than one group of people living in the dwelling that pooled their money and shared their food together. In this survey, there were four cases on Funafuti only. Three of these dwellings had two households reside in them, whereas one dwelling had three households
The fieldwork was carried out by 42 specially selected interviewers and 13 supervisors, supported by 2 trainers and 4 staff of the Central Statistics Division who acted as supervisors. The interviewers were selected via a recruitment process, with preference given to those applicants who had previous survey experience with the Central Statistics Division. Interviews were conducted to select the final list of interviewers. The supervisors did the training of fieldworkers on the Outer Islands and also assisted in the supervision of the fieldwork.
There was a one-week training course for supervisors, followed by a one-week training course for interviewers (also attended by the supervisors). All field staff had to swear and sign an oath of confidentiality.
The survey was publicized by means of radio - that is an interview was broadcasted by Radio Tuvalu to inform the public about the survey. Fieldwork for each island lasted about 3-4 weeks. This involved an initial few days for becoming familiar with the work area each enumerator was responsible for, and making an initial contact with the selected households to drop off the diaries. The households then had two weeks for completion of the diaries, and during this period the interviewers would call in from time to time to check that the recording of daily expenditures was proceeding satisfactorily. They would also use the occasion of their visits to collect some of the information required for the household and individual schedules. They would then make a final visit to the households to collect the diaries, and after checking the questionnaires, they passed them to their supervisors.
Respondent Error
Whether intentional or not, respondents in the household will at times provide incorrect information to questions, despite how well the question is worded and asked by the interviewer. This may sometimes be because the respondent may not wish the interviewer to know the true amount and intentionally provide an incorrect answer, which happens at times for income, or they simply misunderstood the question. A common misunderstanding for questions in a HIES is the reference period being referred. Interviewers are trained to reduce the likelihood of this error as much as possible.
Consistency of the data:
All data entry, including editing, edit checks and queries, was done using CSPro (Census Survey Processing System) with additional data editing and cleaning taking place in Excel.
The staff from the CSD was responsible for undertaking the coding and data entry, with assistance from an additional four temporary staff to help produce results in a more timely manner.
Although enumeration didn't get completed until mid June, the coding and data entry commenced as soon as forms where available from Funafuti, which was towards the end of March. The coding and data entry was then completed around the middle of July.
A visit from an SPC consultant then took place to undertake initial cleaning of the data, primarily addressing missing data items and missing schedules. Once the initial data cleaning was undertaken in CSPro, data was transferred to Excel where it was closely scrutinized to check that all responses were sensible. In the cases where unusual values were identified, original forms were consulted for these households and modifications made to the data if required.
Despite the best efforts being made to clean the data file in preparation for the analysis, no doubt errors will still exist in the data, due to its size and complexity. Having said this, they are not expected to have significant impacts on the survey results.
Under-Reporting and Incorrect Reporting as a result of Poor Field Work Procedures
The most crucial stage of any survey activity, whether it be a population census or a survey such as a HIES is the fieldwork. It is crucial for intense checking to take place in the field before survey forms are returned to the office for data processing. Unfortunately, it became evident during the cleaning of the data that fieldwork wasn?t checked as thoroughly as required, and as such some unexpected values appeared in the questionnaires, as well as unusual results appearing in the diaries. Efforts were made to indentify the main issues which would have the greatest impact on final results, and this information was modified using local knowledge, to a more reasonable answer, when required.
Data Entry Errors
Data entry errors are always expected, but can be kept to a minimum with double entry taking place. Unfortunately time did not permit for double entry to take place for the Tuvalu 2010 HIES which will increase the likelihood of such errors. A large number of checks were performed on the final dataset and suspicious results checked against the questionnaires. When errors in data entry were detected during this process the values were rectified, but this could only be possible for suspicious data.
Systematic sampling was adopted for each island in the survey. This was achieved by sorting all households on the island by geographical position and then running a skip of 3 through the list to achieve a 33 per cent sample. Ideally, the approach for calculating sampling errors should be to adopt the formula which best reflects the sample design, but for this report, it was decided to adopt the formula assuming "simple random sampling" was adopted. This made things a lot simpler and this approach is a more then suitable approximation.
It was not possible to calculate sampling errors for all estimates in this report, so just some sample errors for key estimates of expenditure and income were produced for selected geographical areas. This in itself should give users a guide as to what can be expected from results with respect to sampling errors.
The procedure for addressing this was to firstly calculate the variance associate with key estimates, convert these to standard errors, and then represent these standard errors as a percentage of the estimate. Such a figure is referred to as a relative standard error (RSE) and is useful for comparing the quality of different size estimates from a survey.
Please refer to Section 4 of the HIES 2010 Report for details.
Non-response Bias
Name | Affiliation | URL | |
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Government Statistician | Central Statistics Division | http://www.spc.int/prism/tuvalu/ | statistics@tuvalu.tv |
Use of the dataset must be acknowledged using a citation which would include:
Example:
Central Statistics Division, Tuvalu. Household Income and Expenditure 2010. Ref. TUV_2010_HIES_v01_M. Dataset downloaded from [source] on [date].
The user of the data acknowledges that the original collector of the data, the authorized distributor of the data, and the relevant funding agency bear no responsibility for use of the data or for interpretations or inferences based upon such uses.
Name | Affiliation | URL | |
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Government Statistician | Central Statistics Division | statistics@tuvalu.tv | http://www.spc.int/prism/tuvalu/ |
DDI_TUV_2010_HIES_v01_M
Name | Affiliation | Role |
---|---|---|
Toakai. PUAPUA | Secretariat of the Pacific Community | Documentation of survey metadata |
Accelerated Data Program | International Household Survey Network | Editing for the IHSN Survey Catalog |
2011-02-16
Version 01 (September 2012) - Adapted version of the DDI "DDI-TUV-SCD-HIES-2010-v01" documented by SPC in February 2011.