Implementing Coding Tools for a New Classification

1
Implementing Coding Tools for a New Classification

• John Perry, UK Office for National Statistics

2
Operation 2007 - The players

• In the UK The Standard Industrial
  Classification of Economic Activities (SIC)
  (current version SIC (2003)
• In Europe NACE, the Nomenclature générale
  des activités économiques dans les
  Communautés européens (current version NACE
  Rev 1.1)
• In the UN ISIC, the International Standard
  Industrial Classification of all Economic
  Activities (current version ISIC Rev
  3.1)

3
The UK SIC

• is a 5 digit classification system
• is required, by EU legislation, to be identical
  to NACE down to and including the 4 digit Class
  level
• contains a national 5th digit level which does
  not exist in NACE

4
The Results changes in structure
5
ACTR as an aid to coding

• ACTR Automatic Coding by Text Recognition
• Developed by Statistics Canada
• ONS standard tool for coding, initially industry
  and occupation
• Replaces Precision Data Coder for industry coding
• Determines a code from a text description
• Extent of automation of process is controlled by
  parameters

6
Knowledge Bases SIC2003

• ACTR relies heavily on indexes of standard
  descriptions
• Business descriptions from responses to the
  Business Register Survey
• Published index for the SIC2003
• The short descriptions for each SIC2003 code
• Standard descriptions for construction industry
  statistics
• Trade code descriptions for PAYE (Pay As You Earn
  Tax) employers
• Farm type descriptions
• With a total of gt 30,000 standard descriptions

7
How ACTR works

• Each input description is converted to a standard
  form
• This is compared with the standard forms of
  descriptions held in the knowledge base
• The closeness is presented as a score between 0
  and 10
• The system has rules to determine whether the
  score is sufficient to confirm a match
• Requires a score of more than 7.5 to code
  automatically (our setting which may differ for
  other data sets)
• Lower scores are passed through interactive
  coding
• Coding does not depend on the order in which the
  knowledge bases are checked

8
Extract from Business Register Survey
Questionnaire
9
(No Transcript)
10
(No Transcript)
11
(No Transcript)
12
ACTR Process

• Supplied text Horticultural services
• HORTICULTURAL SERVICE
• Best fit index entry Sales and service of
  horticultural machinery
• HORTICULTURAL MACHINERY SALE SERVICE
• Score is 6.911 (out of 10)
• ACTR prefers SIC 2003 code 51880 (Wholesale of
  agricultural machinery and accessories)

13
(No Transcript)
14
Interactive coding

• Scores below 7.5 are passed to clerical staff for
  coding interactively
• The system presents options in descending order
  of score
• If none of the choices appear good, staff modify
  the description
• Once a decision is made, the person coding
  confirms the choice
• The index description is then held on the IDBR.

15
Introducing the SIC2007 (NACE Rev 2)

• New index files
• SIC2007 headings
• SIC2007 index
• Initially code forward from the SIC2003 using
  bridging codes these are codes for each
  knowledge base entry that link the SIC2003 and
  SIC2007
• Later will change to code backwards from the
  SIC2007
• Eventually dual coding will cease

16
Impact of ACTR on IDBR at Micro Level

• Existing SIC 2003 is 01120 (Growing of vegetables
  etc)
• The preferred ACTR SIC 2003 is 51880 (Wholesale
  of agricultural machinery and accessories)
• The SIC 2007 comes from the bridging code
• SIC 2003 51880
• Bridging code MTOLR
• SIC 2007 46610
• SIC 2003 code will change but only when agreed

17
Conversion to SIC2007

• ACTR will deal with units that have a suitable
  business description
• Conversion tables will deal with
• Units with descriptions that ACTR is unable to
  code (vague descriptions)
• Units without a description
• Units supplied through administrative sources
  (existing VAT traders, PAYE employers, Registered
  Companies)

18
Creation of Conversion Tables

• Tables have been created to convert units from
  SIC2003 to SIC2007
• Using ACTR bridging codes
• Coding existing data through ACTR
• Producing cross-tabulation of SIC2003 to SIC2007
• Allocating on a probability basis rounded to
  nearest 5
• Validate relationships against the acceptable
  range of industries
• Best fit tables also produced for users who
  cannot accommodate probability based conversion

19
Codingprocess
20
Impact on the IDBR at the Macro Level

• Impact on SIC 2003 is only on those reporting
  units that have business descriptions for local
  units, where ACTR can code.
• ACTR codes 620,000
• ACTR does not code 210,000
• No business description 340,000
• Administrative data only 1,660,000
• Total local units 2,830,000
• SIC 2007 comes from the bridging codes only where
  ACTR codes otherwise SIC 2007 comes from
  conversion from SIC 2003

21
A AGRICULTURE, HUNTING AND FORESTRY SIC
2003 B FISHING C MINING AND QUARRYING D MANUFACTUR
ING E ELECTRICITY, GAS AND WATER SUPPLY F
CONSTRUCTION G WHOLESALE AND RETAIL TRADE
REPAIR OF MOTOR VEHICLES H HOTELS AND
RESTAURANTS I TRANSPORT, STORAGE AND
COMMUNICATION J FINANCIAL INTERMEDIATION K REAL
ESTATE, RENTING AND BUSINESS ACTIVITIES L
PUBLIC ADMINISTRATION AND DEFENCE COMPULSORY
SOCIAL M EDUCATION N HEALTH AND SOCIAL
WORK O OTHER COMMUNITY, SOCIAL AND PERSONAL
SERVICE ACTIVITIES P PRIVATE HOUSEHOLDS
EMPLOYING STAFF AND UNDIFFERENTIATED Q
EXTRA-TERRITORIAL ORGANISATION AND BODIES
22
Impact at SIC 2003 broad industry level
(provisional counts)
23
A Agriculture, Forestry And Fishing SIC
2007 B Mining And Quarrying C Manufacture D Electr
icity, Gas, Steam And Air Conditioning
Supply E Water Supply Sewage, Waste Management
And Remediation Activities F Construction G Wholes
ale And Retail Trade Repair Of Motor Vehicles
And Motorcycles H Transportation And
Storage I Accommodation And Food Service
Activities J Information And Communication K Finan
cial And Insurance Activities L Real Estate
Activities M Professional, Scientific And
Technical Activities N Administrative And Support
Service Activities O Public Administration And
Defence Compulsory Social Security P Education Q
Human Health And Social Work Activities R Arts,
Entertainment And Recreation S Other Service
Activities T Activities Of Households
U Activities Of Extraterritorial Organisations
And Bodies
24
Correspondence between SIC 2003 and SIC 2007 for
local units coded by ACTR
25
Implementation timetable
26
Conclusions

• The ACTR tool delivers considerable savings in
  terms of cost and burden on businesses compared
  to traditional survey approaches.
• The knowledge base is portable (i.e. independent
  of the coding engine), enabling sharing this with
  any interested parties, e.g. administrative data
  suppliers, to increase the consistency of coding.
• The use of bridging codes permits simultaneous
  coding to multiple classification systems,
  essential if periods of dual-coding are required.
  
• The knowledge base approach can help to inform
  the development of future versions of a
  classification, by providing a reference frame of
  business activity descriptions.