Transcript Dissemination Workshop for African countries on the Implementation of International Recommendations for Distributive Trade Statistics 27-30 May 2008, Addis Ababa, Ethiopia UNITED NATIONS STATISTICS.

Dissemination
Workshop for African countries on the Implementation of International
Recommendations for Distributive Trade Statistics
27-30 May 2008, Addis Ababa, Ethiopia
UNITED NATIONS STATISTICS DIVISION
Trade Statistics Branch
Distributive Trade Statistics Section
Outline of the presentation
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National reporting
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Statistical confidentiality
Data dissemination timetable
Data revisions
International reporting
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List of data items on DTS recommended
for international reporting
National reporting
Data dissemination
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Key activity of NSOs
Responsibilities of NSOs
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Provide policy makers, business community
and other users with high quality statistical
information
Motivate respondents to participate in
statistical surveys
Protect confidentiality of respondents
Statistical confidentiality
Most of the information about individual statistical
units classified in section G of ISIC, Rev.4 is
considered to be confidential
Statistical confidentiality is necessary in order to
gain and keep the trust of:
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Those required to respond to statistical surveys
Those using the statistical information
UN Fundamental Principles of Official Statistics (the
sixth principle)
National Statistical Laws or other supplementary
governmental regulations
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National definitions of confidentiality and rules for
microdata access may differ, but they should be consistent
with this fundamental principle
DTS and statistical confidentiality
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NSOs usually disseminate DTS in the form of various
statistical tables
The statistical confidentiality is protected if tabulated
data do not allow statistical units to be identified
either directly or indirectly, thereby disclosing
individual information
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Direct identification - if data of only one statistical unit
are reported in a cell
Indirect identification - if individual data can be derived
from disseminated data (e.g. because there are too few
units in a cell, or because of the dominance of one or
two units in a cell)
Statistical disclosure control
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Set of methods to reduce the risk of disclosing
information on individual units
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Manifest themselves at the dissemination stage,
however
Pertinent to all stages of statistical production process
Disclosure control methods - attempt to find an
optimal balance between the improvement in
confidentiality protection and the reduction in data
quality
Identification of sensitive cells - first step in statistical
disclosure control
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Sensitive cells – cells that tend to reveal directly or
indirectly information about individual statistical units
Methods for protecting confidentiality
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Aggregation
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Suppression
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A confidential cell in a table is aggregated with another cell
and then the information is disseminated for the aggregate
and not for the two individual cells
Removing records from a database or a table that contains
confidential data
Primary suppression - values in sensitive cells are not
published while the original values of the others are
Secondary suppression - some other cells are also
suppressed to guarantee the protection of the values under
the primary suppression
Other methods
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Control rounding – the original value of each cell is modified
by rounding it up or down to a near multiple of a base
number
Perturbation – linear programming variant of the controlled
rounding technique
Confidentiality rules for DTS
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Rules for protecting confidentiality of DTS - should be
in line with the provisions of countries national
legislation and practice
Confidentiality criteria
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Number of units in a tabulation cell
Dominance of a unit or units contribution over the total value
of a tabulation cell
Decision in respect to the exact definition of the
confidentiality criteria in terms of number of units per
cell and percentage of dominance - left to the NSOs
Confidentiality rules may be relaxed in individual cases
by requesting the permission of the dominating
respondent (s) to disclose their data
Recommendations
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Countries are encouraged to develop their
own statistical disclosure methods suiting
best their specific circumstances
If suppression is preferred as a method for
protecting confidentiality of DTS
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Any data deemed confidential should be reported
in full detail at the next higher level of
classification that adequately protect
confidentiality
The confidentiality protection must result in a
minimum loss of information
Data dissemination timetable (1)
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Advance release calendar
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Guarantees well established relations between
NSOs as producers of DTS and the user community
Countries should develop and announce in advance
the precise dates at which DTS statistics will be
released
To be posted in the beginning of each year on the
country’s statistical office website
Timelines of DTS data
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Monthly – 45 days after the reference month
Quarterly – 3 months after the end of the quarter
Annual – 18 months after the end of the year
Data dissemination timetable (2)
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Issues of importance for the
development of advance release
calendar
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Timing of collection of initial data from
major DTS surveys
To what extent data derived from the major
data sources are subject to revisions
Timing of preparation of important national
economic policy documents that need DTS
as inputs
Modes of data dissemination
Data revisions
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Essential part of countries practices on
compilation of DTS
Occur as a consequence from the trade-off
between the timeliness of published data and
their reliability, accuracy and
comprehensiveness
Conducted for the benefit of users - to provide
them with data that are as timely and accurate
as possible
Affect both annual and short-term DTS but are
more pronounced for the short-term data
Reasons for revision
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Revisions due to “normal” statistical procedures
(current revisions) - conducted at regular intervals of
time
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New information becomes available
Change in the methodology
Change in data source
Change of base year
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Revisions due to the correction of errors that may
occur in source data or in processing
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Special revisions - carried out at longer, irregular
intervals of time
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Re-assessing the data
Investigating in depth some new economic structures
Revision policy
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Countries are encouraged to develop a welldesigned, carefully managed and coordinated with
other areas of statistics revision policy for DTS
Essential features of a well-established revision
policy
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Predetermine schedule
Reasonable stability from year to year
Openness
Advance notice of reasons and effects
Easy access of users to sufficiently long time series of revised
data
Adequate documentation of revisions included in the statistical
publications and databases
Dissemination of metadata
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Provision of an adequate metadata and quality
assessment of DTS is as important to users as
provision of data
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Countries are encouraged to develop and
disseminate metadata on DTS
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Metadata components
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Data coverage, periodicity and timeliness
Access by the public
Integrity of disseminated data
Data quality
Summary methodology
Dissemination formats
International reporting – Annual data
Code
Data item
A
1.10
Demography
Number of enterprises
B
2.1
Employment
Total number of persons
employed
Total number of employees
2.1.3
C
3.1
H
8.1
8.1.1
J
10.1
K
Compensation of
employees
Wages and salaries in cash
and in kind of employees
Output
Gross output at basic prices
Gross margin
Value added
Total value added at basic
prices
Gross Fixed Capital
Formation
Level of details
Minimum
requirements
(in terms of ISIC,
Rev.4)
Deadline
By activity and
size class
3-digit level for
activity breakdown
1-digit level for size
class breakdown
18 months
By activity and
size class
By activity and
size class
- do -
18 months
- do -
18 months
By activity
3-digit level
18 months
By activity
By activity
-do -do -
18 months
18 months
By activity
-do -
18 months
1-digit level
18 months
International reporting – Quarterly data
Code
B
2.1
2.1.3
C
3.1
E
5 (a)
Data item
Employment
Total number of persons
employed
Total number of employees
Compensation of
employees
Wages and salaries in cash
and in kind of employees
Turnover
Turnover
Level of details
Minimum
requirements
(in terms of ISIC,
Rev.4))
Deadline
By activity
2-digit level
3 months
By activity
2-digit level
3 months
By activity
2-digit level
3 months
By activity
2-digit level
3 months
International reporting – Monthly data
Code
Data item
Wholesale and retail trade
turnover indices (value
and/or volume)
Level of details
Broken down by
activity
Minimum
requirements
(in terms of
ISIC, Rev.4)
2-digit level
Deadline
45 days for retail
trade (division 47
of ISIC, Rev.4)
60 days for
wholesale trade
and motor vehicle
trade (divisions
45 and 46 of
ISIC, Rev.4)
Thank You