Transcript SiStaN in Brief

European conference on quality in official statistics
Rome, 8-10 July 2008
How to assess the quality of the Italian
classification of occupations
Francesca Gallo
Pietro Scalisi
Aim of the presentation
 How to transpose and adapt Eurostat
definition of quality which is thought for a
statistic to the sphere of a classification
 Results of our assessment as far as the
classification of occupation is concerned
 Actions and instruments we have set up in
order to better meet quality criteria
Comparability
Statistic: “…extent to which differences between
statistics are attributed to differences between
the true values of the statistical characteristic”
Classification: differences between statistics
collected in different countries or at different
times should not be addressed to the
classification tool
Comparability
The Italian classification of occupation is a
derivation of the International Standard
Classification of Occupation
(ISCO88 and ISCO08)
A clear mapping of the national
classification into the international one
makes space comparison feasible
Relevance
Statistics: “… degree to which statistics meet
current and potential users’ needs”
Classifications: … degree to which classifications
meet current and potential users’ needs
Relevance
The need to better satisfy users’ needs (labour market
researchers, policy makers) led Istat to improve the 2001
National classification of occupation
Nomenclature of the occupational units (2006)
 adds a further digit (the 5th) to the 2001 classification,
i.e. splitting the 519 4-digit codes into 805 5-digit codes;
 gives a general description of the tasks and duties of the
5-digits involved in the classification.
Accessibility and clarity
Download version
Occupations quick search
Accessibility and clarity
Look-up the
5-digit structure
Accessibility and clarity
Occupations descriptions
Accessibility and clarity
Isco 88
code
Coherence
Statistics: “…. statistics originating from different
sources convey coherent messages”
Classification:
…criteria
inspiring
the
classification structure are in accordance with
data on occupations coming out from
statistical sources
Coherence
Do Isco (and the derived national
classification) criteria comply with
the characteristics of the Italian
occupations stemming from
statistical surveys?
Coherence
Isco is based on the concept of skill level
MAJOR GROUPS
1. LEGISLATORS, SENIOR OFFICIALS
AND MANAGERS
2. PROFESSIONALS
Education level
(ISCED)
as a skill level
proxy
6+7
3. TECHNICIANS
5
4. CLERKS
2
5. SERVICE AND SALES WORKERS
2
6. CRAFT, TRADES AND AGRICULTURAL
SKILLED WORKERS
7. PLANT AND MACHINE OPERATORS
2
8. ELEMENTARY OCCUPATIONS
1
9. ARMED FORCE
-
2
Coherence
What are the leading characteristics of the
occupations performed in the Italian labour market?
Istat survey on occupation
The object was :
 to describe 805 occupational units (the 5th
digit of the classification of occupation) in
terms of skills, knowledges, abilities,
generalised work activities, … requirements.
Coherence
A sketch of the survey on occupations
 A sample of workers of a given occupational unit
is asked to assess the importance and level of a
given set of skills, knowledges, abilities,
generalised work activities needed to perform their
current job.
 Their answers are used to obtain an occupational
unit mean profile in term of skills, knowledge,
abilities, generalised work activities requirements
Coherence
A sketch of the survey results
Table - Importance of a given skill for the performance of the occupation (values range 0-100)
Occupations
Skills (a given set of 35 skills)
Occ_1
Occ_2
Occ_3
..
Occ_n=805
Writing
90
82
43
..
88
Speaking
10
66
54
..
100
Active learning
20
60
44
..
19
Monitoring
23
43
40
..
54
Problem identification
7
54
30
..
44
Negotiation
45
44
20
..
40
Service orientation
12
40
23
..
30
Reparing
88
30
7
..
82
Judgement and decision making
100
82
45
..
33
Time management
19
66
12
..
77
..
..
..
..
..
..
Management of Personnel resources
67
60
56
..
28
Coherence
The observed skills.
P
R
O
D
U
C
T
I
O
N
Is it consistent with the classification criteria?
V
E
R
S
U
S
S
E
R
V
I
C
E
S
Manual activities



versus
Intellectual activities
PLANT AND MACHINE OPERATORS
Installation
Repairing
Monitoring
machines
CRAFT, TRADES AND
AGRICULTURAL SKILLED WORKERS



Complex problem solving
Time management
Critical Thinking
TECHNICIANS
PROFESSIONALS
LEGISLATORS, SENIOR OFFICIALS AND MANAGERS
SERVICE AND SALES WORKERS
ELEMENTARY OCCUPATIONS


Equipment
maintenance
Monitoring machines

Controlling equipments


Service orientation
Social Perceptiveness

Adaptability
CLERKS
Timeliness
Statistic: “… the length of time between
information availability and the event or
phenomenon it describes”
Classification: it should integrate the changing
signals coming from the world of occupations
as soon as they occur
Timeliness
The feedback from the real world
 The classification is used in the labour force
survey
 The feedback coming from the interviewers
network will help us to understand and
integrate the changing signals of the
occupation world into the classification
Accuracy
Statistics: “… the closeness of estimates to the
exact or true values”
Classification: the closeness of the codes
attributed to a given occupation by different
interviewers to the exact code
Accuracy
True code
Codes attributed by:
Interviewer_1
3.2.1.6.1 – Dietist
Interviewer_2
…………
Interviewer_n
MSE can be caused either by the classification
tool and by the interviewer’s effect
Classification
tool
Accuracy
 Monitoring action to estimate the ‘wrong-code’
percentage in the Labour Force Survey
 concentration of the wrong codes in some specific place
of the classification
This led us to
 add more details to the definitions of those specific
occupations and to plan training sessions in order to
make the use of the classification instrument as
objective as possible