The documented dataset covers Enterprise Survey (ES) panel data collected in Yemen in 2010 and 2013, as part of the Middle East and North Africa Enterprise Surveys rollout, an initiative of the World Bank.
New Enterprise Surveys target a sample consisting of longitudinal (panel) observations and new cross-sectional data. Panel firms are prioritized in the sample selection, comprising up to 50% of the sample in the current wave. For all panel firms, regardless of the sample, current eligibility or operating status is determined and included in panel datasets.
Yemen ES 2013 was conducted between March 2013 and July 2014 as part of the joint World Bank, European Bank for Reconstruction and Development (EBRD) and European Investment Bank (EIB) Enterprise Survey. Yemen ES 2010 was carried out between March and June 2010.
The objective of the Enterprise Survey is to obtain feedback from enterprises on the state of the private sector as well as to help in building a panel of enterprise data that will make it possible to track changes in the business environment over time, thus allowing, for example, impact assessments of reforms. Through interviews with firms in the manufacturing and services sectors, the survey assesses the constraints to private sector growth and creates statistically significant business environment indicators that are comparable across countries.
Stratified random sampling was used to select the surveyed businesses. The data was collected using face-to-face interviews.
Data from 830 establishments was analyzed: 214 businesses were from 2013 ES only, 338 - from 2010 ES only, and 278 firms were from both 2010 and 2013 panels.
Kind of data
Sample survey data [ssd]
Regions covered are selected based on the number of establishments, contribution to employment, and value added. In most cases these regions are metropolitan areas and reflect the largest centers of economic activity in a country.
Unit of analysis
The primary sampling unit of the study is an establishment. An establishment is a physical location where business is carried out and where industrial operations take place or services are provided. A firm may be composed of one or more establishments. For example, a brewery may have several bottling plants and several establishments for distribution. For the purposes of this survey an establishment must make its own financial decisions and have its own financial statements separate from those of the firm. An establishment must also have its own management and control over its payroll.
The whole population, or universe of the study, is the non-agricultural economy. It comprises: all manufacturing sectors according to the group classification of ISIC Revision 3.1: (group D), construction sector (group F), services sector (groups G and H), and transport, storage, and communications sector (group I). Note that this definition excludes the following sectors: financial intermediation (group J), real estate and renting activities (group K, except sub-sector 72, IT, which was added to the population under study), and all public or utilities-sectors.
Producers and sponsors
European Bank for Reconstruction and Development
European Investment Bank
European Bank for Reconstruction and Development
European Investment Bank
For Yemen ES 2013, two sample frames were used. The first was supplied by the World Bank and consisted of enterprises interviewed in Yemen in 2010. The World Bank required that attempts were made to re-interview establishments responding to the Yemen 2010 Enterprise Survey where they met eligibility criteria. This sample is referred to as the panel. The second sample frame, referred to as a fresh sample, was obtained from the Central Statistics Office, 2010 Establishment Census, with updates and validation provided by the Yemen Polling Center (YPC).
Survey non-response must be differentiated from item non-response. The former refers to refusals to participate in the survey altogether whereas the latter refers to the refusals to answer some specific questions. Enterprise Surveys suffer from both problems and different strategies were used to address these issues.
Item non-response was addressed by two strategies:
a- For sensitive questions that may generate negative reactions from the respondent, such as corruption or tax evasion, enumerators were instructed to collect the refusal to respond as a different option from don’t know.
b- Establishments with incomplete information were re-contacted in order to complete this information, whenever necessary.
Survey non-response was addressed by maximizing efforts to contact establishments that were initially selected for interview. Attempts were made to contact the establishment for interview at different times/days of the week before a replacement establishment (with similar strata characteristics) was suggested for interview. Survey non-response did occur but substitutions were made in order to potentially achieve strata-specific goals.
For some units it was impossible to determine eligibility because the contact was not successfully completed. Consequently, different assumptions as to their eligibility result in different universe cells' adjustments and in different sampling weights. Three sets of assumptions were considered:
a- Strict assumption: eligible establishments are only those for which it was possible to directly determine eligibility.
b- Median assumption: eligible establishments are those for which it was possible to directly determine eligibility and those that rejected the screener questionnaire or an answering machine or fax was the only response. Median weights are used for computing indicators on the www.enterprisesurveys.org website.
c- Weak assumption: in addition to the establishments included in points a and b, all establishments for which it was not possible to finalize a contact are assumed eligible. This includes establishments with dead or out of service phone lines, establishments that never answered the phone, and establishments with incorrect addresses for which it was impossible to find a new address. Note that under the weak assumption only observed non-eligible units are excluded from universe projections.
Dates of collection
Mode of data collection
The following survey instruments were used for Yemen 2013 ES:
- Manufacturing Questionnaire;
- Services Questionnaire.
The survey is fielded via manufacturing or services questionnaires in order not to ask questions that are irrelevant to specific types of firms, e.g. a question that relates to production and nonproduction workers should not be asked of a retail firm. In addition to questions that are asked across countries, all surveys are customized and contain country-specific questions. An example of customization would be including tourism-related questions that are asked in certain countries when tourism is an existing or potential sector of economic growth.
The eligible manufacturing industries have been surveyed using the Manufacturing Module Questionnaire (includes a common set of core variables, plus manufacturing specific questions). Eligible service establishments have been covered using the Services Module Questionnaire. Each variation of the questionnaire is identified by the index variable, a0.
All variables are named using, first, the letter of each section and, second, the number of the variable within the section, i.e. a1 denotes section A, question 1. Variable names proceeded by a prefix "MNA" indicate questions specific to the Middle East and North Africa region, therefore, they may not be found in the implementation of the rollout in other countries. All other suffixed variables are global and are present in all economy surveys over the world. All variables are numeric with the exception of those variables with an "x" at the end of their names. The suffix "x" denotes that the variable is alpha-numeric.
The following survey instruments were used for Yemen 2010 ES:
- Core Questionnaire + Manufacturing Module [ISIC Rev.3.1: 15-37]
- Core Questionnaire + Retail Module [ISIC Rev.3.1: 52]
- Core Questionnaire [ISIC Rev.3.1: 45, 50, 51, 55, 60-64, 72]
The "Core Questionnaire" is the heart of the Enterprise Survey and contains the survey questions asked of all firms across the world. There are also two other survey instruments- the "Core Questionnaire + Manufacturing Module" and the "Core Questionnaire + Retail Module."
Data collection in 2010
Data collection in 2013
Yemen Polling Center
Data collection in 2013
Data entry and quality controls are implemented by the contractor and data is delivered to the World Bank in batches (typically 10%, 50% and 100%). These data deliveries are checked for logical consistency, out of range values, skip patterns, and duplicate entries. Problems are flagged by the World Bank and corrected by the implementing contractor through data checks, callbacks, and revisiting establishments.
Confidentiality of the survey respondents and the sensitive information they provide is necessary to ensure the greatest degree of survey participation, integrity and confidence in the quality of the data. Surveys are usually carried out in cooperation with business organizations and government agencies promoting job creation and economic growth, but confidentiality is never compromised.
The use of the datasets must be acknowledged using a citation which would include:
- the identification of the Primary Investigator (including country name);
- the full title of the survey and its acronym (when available), and the year(s) of implementation;
- the survey reference number;
- the source and date of download (for datasets disseminated online).
World Bank, European Bank for Reconstruction and Development, European Investment Bank. Yemen, Rep. Enterprise Survey (ES) 2010-2013, Panel Data. Ref. YEM_2010-2013_ES-P_v01_M. Dataset downloaded from [URL] 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.