DLV011 Summary report on ESCO skills pillar pilot...DLV011 – Summary report on ESCO skills pillar pilot Results and lessons learnt 4 of 28 Skills hierarchy The results of structuring

DLV011 – Summary report on ESCO skills pillar pilot

1. The current structure of the ESCO skills pillar ........................................... 6

2. Current trends ............................................................................................ 12

3. Objective and scope of the pilot ................................................................ 14

4. The methodology of the pilot .................................................................... 14

5. Results and lessons learnt .......................................................................... 19

6. Recommendations ..................................................................................... 26

7. Open issues ................................................................................................ 27

DLV011 – Summary report on ESCO skills pillar

pilot

Document version and date : Version 1.1

2018-05-16


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Document Metadata Property Value

Release date 2018-05-16

Status Draft

Version 1.0

Authors Aikaterini Sylla

Honza Förster

Reviewed by

Approved by

Document History Version Date Description Action

1.0 2018-04-30 First release For acceptance

1.1 2018-05-16 Updated release For acceptance


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Executive summary

Purpose of the document

The purpose of this document is to provide the ESCO Maintenance Committee with a

short overview of the ESCO skills hierarchy1 pilot which was carried out between 10

November 2017 and 15 March 2018. This would allow the ESCO Maintenance

Committee to become more familiar with the ESCO skills hierarchy in view of the June

2018 meeting, where the Commission intends to discuss with the committee the further

development of the skills pillar.

The scope of the pilot

In the context of the skills hierarchy pilot, the ESCO team tested various approaches to

structure further the ESCO skills and assess how well those approaches can support the

user needs described above. Those needs are reflected in examples of use cases, as

follows:

Find a concept in the classification

Select groups of concepts for a specific action

The system suggests related concepts

Within the framework of this pilot, the ESCO team tested several structuring approaches

on a sample of the ESCO skills pillar. These are the following:

Skills hierarchy:

DISCO (European Dictionary of Skills and Competences)2

Kompetenzklassifikation (the skills classification used by the German PES)3

Grouping skills by using other domains as structure/collections:

NACE (Statistical Classification of Economic Activities in the European Union);

ISCED-F (International Standard Classification of Education - Fields of

Education and Training);

CPA (Statistical classification of products by activity);

work context using the work "Arbeitsorte" in the Kompetenzklassifikation

Contextualisation:

analysis of how transversal skills, competences or knowledge are applied in the specific

context of a sector or an occupation.

1 Pyramid-like ranking of skill where every level (except the top and the bottom ones) has one

higher and one lower neighbour. Lower level means more granularity. 2 http://discotools.eu/disco2_portal/ 3 https://download-portal.arbeitsagentur.de/files/login.do

http://disco-tools.eu/disco2_portal/





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Results and lessons learnt

Skills hierarchy

The results of structuring skills with the hierarchy of Kompetenzklassifikation and

DISCO are similar since both classifications i) follow a similar approach to structuring

skill concepts, ii) use a hierarchical grouping of concepts and iii) use sectors of economic

activity to structure sector-specific skills.

Neither contains detailed descriptions of their skill groups that could clarify their scope,

which makes it difficult to assign ESCO skills to the respective groups. Furthermore, both

classifications use economic sectors to classify domain-specific skills. Due to this, they

cannot be easily used as a mono-hierarchical structure, where each skill fits exactly in one

skill group.

Using other domains as structure/collection

Another approach to structuring skills is by expressing how they relate to other types of

concepts. This can be particularly useful for filtered search. The existing relationship

between skills and occupations in ESCO is of this type: it expresses which skills are

normally relevant in the context of an occupation and thus allows the user to filter the

skills pillar by occupation.

NACE

This would allow users to filter on skills that typically contribute to a specific

economic activity. “Load animals for transportation” could, for example, be a skill

relevant, among others, in the economic activities “freight transport by road” and

“animal production”.

In the pilot, several transversal skills were assigned to all NACE sections since they

apply to all sectors of economic activity. There was hardly any ESCO skill that could

be related to only one single NACE section.

The definitions of the NACE sections and the indications of the scope of the section

are very useful to delimit the scope and be accurate in assigning skills.

ISCED-F

The ESCO team assigned skills to the domains of education and training, where these

skills are usually taught. “Load animals for transportation” could, for example, be a

skill taught in education and training programs in the field of “transport services” or

“crop and livestock production”.

The results showed that the ISCED-F classification is valuable and would be

particularly useful when annotating learning outcome descriptions.

CPA

The CPA classification lists services and products in 3,218 subcategories. It proved

difficult to decide on the appropriate relation to skills. It could, for example, express

that knowledge of a certain product or service category is useful for developing a

skill. For example, knowledge of “road transport services of live animals” or of “dairy

cattle, live” is useful for developing the skill “load animals for transportation”.


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Work Context

The Kompetenzklassifikation work context classification is limited to 156 concepts

which are a small number to assign to 13,485 ESCO skills, whereas it is usually not

possible to assign a skill to a single work context. Skills are usually performed in a

range of different locations.

Contextualisation

Contextualisation relations can be established if the description of the skills is clear

enough to define its content and scope. The approach was used when developing ESCO

v1, but it has not been applied consistently over the entire skills pillar.

Therefore, the ESCO team proposes a set of rules for improving the skills descriptions.

This will allow creating more precise and consistent relations. The rules will be listed in

the final report of the pilot project.

Recommendations

Following the results of the pilot, the ESCO team recommends further exploring the use

of ISCED-F and NACE as external classifications to structure ESCO.

Contextualisation is a useful methodology since it provides clear relations among skill

concepts. It can be used for various purposes and the skills pillar is already annotated

with such relations. Furthermore, revising the contextualisation and the methodological

rules related to it would improve the consistency of the skill pillar. On the other hand, it

requires a high effort to manually maintain such relations due to a high number of

concepts in the skills pillar.

DISCO and Kompetenzklassifikation, the two hierarchical skills classifications

evaluated within the scope of this project, use sectors of economic activity to structure

skills. Sectors of economic activity are not suitable as a base for a hierarchical

arrangement of concepts in which each concept can have only one broader concept

(mono-hierarchy), which is the hierarchical arrangement of interest in the case of ESCO,

because a single skill can inherently be related to several different sectors of economic

activity.

Pending issues

The main pending issue identified during the pilot is the lack of an existing suitable

mono-hierarchy that could be used for statistical labour market data purposes. This could

be the default browsing mechanism of the skills pillar. Such classification would have to

be composed of skill groups which are mutually exclusive, i.e. a single skill can be placed

only in a single group, thanks to clear scoping of groups. For the ESCO occupational

pillar, ISCO serves as such a mono-hierarchical structure.

In case a mono-hierarchy of skills would be the most suitable structure to address the user

needs which are reflected in the use case examples, it would be necessary to build a

custom solution for the purposes of ESCO.


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Summary report on the ESCO skills pillar pilot

1. The current structure of the ESCO skills pillar

The skills pillar of ESCO v1 structures 13,485 concepts in four different manners:

• through their relationship with occupations, by using occupations as an entry

point;

• through a hierarchy (only for transversal knowledge, skills and competences);

• through associative4 and contextualised

5 relations (not consistently applied

throughout the entire classification);

• through functional collections grouping only a subset of the skills available that

is of interest for examples of use cases. ESCO v1 includes three functional

collections: digital competences (identical to the Digital Competence

Framework6); language skills and transversal skills.

Covering certain user needs requires the improvement of ESCO's current structure. Such

user needs would include searching for specific skills, doing semantic search, filtering

search results, clustering skills in groups (e.g. language skills, digital skills or

management skills) to work at a more aggregated level, identifying related concepts,

identifying concepts of a specific interest for the user, using only part-subset of the

classification, getting statistics etc. To address this need, the ESCO team developed and

carried out a pilot to arrive at a structure of the ESCO skills pillar that would better serve

such functionalities.

Each one of the manners is described in the sections that follow.

1.1. Relationship with occupations

Each ESCO occupation is related to essential and optional knowledge, skill and

competence concepts. The image on the next two pages shows an example of the

information attached to each ESCO occupation and its relationship to knowledge, skills

and competences.

4 Associative relations indicate how knowledge, skills and competences are relevant to other knowledge, skills and

competences. 5 Skill contextualisation is a method to create knowledge or skill and competence concepts by analysing how

transversal skills, competences or knowledge are applied in the specific context of a sector or an occupation. For more

information and example, you can visit the ESCO portal:

https://ec.europa.eu/esco/portal/escopedia/Skill_contextualisation

6 https://ec.europa.eu/jrc/en/digcomp

https://ec.europa.eu/esco/portal/escopedia/Skill_contextualisation

https://ec.europa.eu/jrc/en/digcomp


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7

Figure 1: ESCO Occupation profile

1.2. Hierarchical relations in the transversal skills

ESCO provides metadata for each concept in the skills pillar. Part of this is the skill

reusability level, which indicates how widely a knowledge, skill or competence concept

can be applied. This is crucial for supporting occupational mobility. ESCO distinguishes

four levels of skill reusability:

• Transversal knowledge, skills and competences: they are relevant to a broad

range of occupations and sectors;

• Cross-sector knowledge, skills and competences: they are relevant to

occupations across several economic sectors;

7 ESCO Handbook, p.15-16. Available at: https://ec.europa.eu/esco/portal/document/en/0a89839c-098d-4e34-846c-

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https://ec.europa.eu/esco/portal/document/en/0a89839c-098d-4e34-846c-54cbd5684d24



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• Sector-specific knowledge, skills and competences: they are specific to one

sector, but are relevant for more than one occupation within that sector;

• Occupation-specific knowledge, skills and competences: they are usually

applied only within one occupation or specialism.

Transversal knowledge, skills and competences are relevant to a broad range of

occupations and economic sectors. They are often referred to as core, basic or soft skills

and are the cornerstone of the personal development of a person.

Within the skills pillar, transversal skills and competences are organised in a hierarchical

structure with the following five headings:

• thinking

• language

• application of knowledge

• social interaction

• attitudes and values

Both the concepts and hierarchical structure of the transversal knowledge, skills and

competences were developed by the Cross-sector Reference Group.8 The development

was based on the analysis of a wide range of existing national and sectoral classifications,

the European Dictionary of Skills and Competences (DISCO)9 and other sources.10 In the

transversal skills, there are hierarchical relations.

Example: The skill group “social interaction” contains as narrower concepts the

following skills, among others:

• report facts;

• persuade others;

• give advice to others.

In addition, there are some hierarchical relations between two skills or small sets which

are not linked to the transversal skills.

Example: The skill “analyse ICT system” is a sector-specific skill which is broader to the

sector-specific skill “identify ICT system weaknesses”.

1.3. Contextualised knowledge, skills and competences

Skill contextualisation is a method to create knowledge or skill and competence concepts

by analysing how transversal skills, competences or knowledge are applied in the specific

context of a sector or an occupation. This allows transversal knowledge, skills and

competences that are abstract to be brought to a more detailed level so that they can be

directly used in occupational profiles.

8 For information about the Cross-sector Reference Group see ESCO Handbook, p.38. Available at:


9 http://disco-tools.eu/disco2_portal/


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Example: The skill “measure” is too abstract to be linked directly to the occupation

“metal furnace operator”. This relationship would produce too many results if used in

competence-based job matching since measuring is relevant for a large number of

occupations and sectors. Through skill contextualisation, the skill can be made more

specific. A skill named “measure furnace temperature” could, for example, be used in the

occupational profile of the “metal furnace operator”.11

Example: The skill “report facts” is too abstract to be linked directly to any sector.

Through skill contextualisation, the skill can be made more specific:

skill named “report pollution incidents” could, for example, be used in the sector of

“agriculture”;

skill named “report mine machinery repairs” could be used for the mining industry;

skill named “report anomalies in aircraft interiors” could be used in the sector of

transport.

1.4. Associative relations

Apart from hierarchical relations, there are also associative relations between skills. An

associative relation between two skills indicates that a skill is essential or optional to

carry out another skill.

Example: The skill “think creatively” is essential to design greeting cards and write

storylines.

11 ESCO Handbook, p.20. Available at: https://ec.europa.eu/esco/portal/document/en/0a89839c-098d-4e34-846c-

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The diagram below illustrates the current hierarchical and associative relations in the

ESCO skills pillar. The green arrows refer to the hierarchical relations while the red

arrows to the associative relations. The diagram can be interpreted as follows:

• the triangle depicts the hierarchical relations among the transversal skills;

• the skills in the red box are contextualized ones. The green arrows show the

relations among them but also with the transversal skills in the triangle;

• the rest of the relations on the left reflect relations among small sets of skills

which are not linked to the transversal skills;

• the skills with no relation established are orphans.

Figure 2: ESCO Associative relations

1.5. Functional collections

Functional collections allow subsections of the skills pillar to be selected, according to

the purpose it is going to be used for.

Example: An organisation may want to use ESCO to implement an online CV editor

where a user can indicate his/her language skills. The organisation would not need all

the ESCO skills in that CV section, only the language skills. If a user searches for

"Chinese" in this section, the system should suggest "Chinese", "understand spoken

Chinese", “understand written Chinese” or "interact verbally in Chinese", but not

"traditional Chinese medicine" or "give shiatsu massages".

A functional collection would allow the user to pick exactly the skills (or occupations)

s/he is looking for. ESCO v1 includes three functional collections: Digital transversal

skills (identical to the Digital Competence Framework); Language skills; Transversal

skills.12


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2. Current trends

This section describes external ongoing initiatives which deal with the structuring of skill

information and labour market data in general:

2.1. Google Cloud Job Discovery (formerly Cloud Jobs API)

Google Cloud Job Discovery13 is a service which enables third party services, e.g. job

boards, to enrich their search algorithm with Google data based on machine learning

analysis of the labour market. Google defines the tools as follows:

“Cloud Job Discovery is part of Google for Jobs - a Google-wide commitment to help

people find jobs more easily. Job Discovery provides plug and play access to Google’s

search and machine learning capabilities, enabling the entire recruiting ecosystem -

company career sites, job boards, applicant tracking systems, and staffing agencies to

improve job site engagement and candidate conversion.”

The tool allows third-party services to perform a wide range of enrichment, such as:

- Recognise jargon used by employers in job vacancies and by job searchers:

Figure 3: Recognising jargon

13 https://cloud.google.com/job-discovery/


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- Recognise searches which have multiple interpretations and variations in order to

list the most relevant results:

Figure 4: Understanding underlying concept

2.2. Cedefop Job vacancy search

Job vacancy search is an initiative, currently under development, by Cedefop to carry out

analysis of vacancies and emerging skill requirements across all EU Member States. The

real-time data collection system is aimed at collecting relevant background characteristics

of jobs, firms and the type of employee they are looking for, e.g. skills, qualifications and

other attributes, to enable the analysis of skills demand.

Once it is completed, Cedefop will be able to retrieve job vacancy information from job

boards of Member states and provide analysis on this data. The knowledge gathered can

then be used, among many other uses, to improve the ESCO classification by providing

real-world information on the usage of skills and occupations. Such statistics can drive

the development of content and terminology of ESCO during its continuous

improvement.

2.3. OPENSKIMR

Open European Skill Match Maker (OPENSKIMR) is an EU-funded project that aims to

create a skill-matchmaking between talents, and jobs and the required learning to support

people in creating their personal career routes. This project is based on:

ESCO

a set of algorithms that match talents with the perfect fitting job and in addition,

suggest learnings which shall be supported in evolving personal career routes of

future STEM talents.

It is a tool which aims to support people individually with their personal career path and

combines life-long-learning opportunities with specific job offers.

http://openskimr.eu/


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3. Objective and scope of the pilot

In the context of the skills hierarchy pilot, the ESCO team tested various approaches to

structure further the ESCO skills and assess how well those approaches can support the

user needs described above. Those needs are reflected in examples of use cases, as

follows:

• Find a concept in the classification

Example: an education provider searches for skills to insert into the learning outcomes

description of a qualification

• Select groups of concepts for a specific action

Example: an employer wants to select a group of skills when preparing a job vacancy

description, instead of picking all skills individually

• The system suggests related concepts

Example: A candidate receives suggestions for skills to complement her/his CV.

4. The methodology of the pilot

4.1. Select the ESCO skill dataset sample

The subset should include cross-sectoral, sector and occupation-specific skills as well as

the entirety of the transversal skills. The selection was based on ISCO-08 using the

relationship between skills and occupation profiles. As a result, the ESCO team extracted

in total 610 skills from the ESCO occupations related to the following two major ISCO

groups:

• ISCO-08 514: Hairdressers, beauticians and related workers

• ISCO-08 2432: Public relations professionals

These include:

skills/competences that are linked to the ESCO occupations of each of the ISCO

groups

skills/competences that are linked to one or more occupations of both ISCO

groups

skills/competences that are transversal to occupations of more ISCO groups

ISCO group ESCO occupations ESCO skills

514: Hairdressers, beauticians

and related workers 17 occupations 272

2432: Public relations

professionals 11 occupations 218

514 and 2432 13 cross-sectoral skills

514 and 2432 + more 107 transversal skills

Table 1: Overview of skill sample


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4.2. Select the structuring approaches

The objective of the pilot was to explore various approaches to further structure the

ESCO skills and assess how well these approaches can support the user needs described

in section 3 Objective and scope of the pilot.

Within the framework of this pilot, the ESCO team tested several structuring approaches

on a sample of the ESCO skills pillar. These are the following:

• Skills hierarchy:

o Applying the hierarchy of DISCO (European Dictionary of Skills and

Competences) to ESCO skills14

;

o Applying the hierarchy of Kompetenzklassifikation (the skills

classification used by the German PES) to ESCO skills15;

• Grouping skills by using other domains as structure/collections:

o By economic activity using NACE (Statistical Classification of Economic

Activities in the European Union)16

;

o By fields of education and training using ISCED-F (International

Standard Classification of Education - Fields of Education and Training)

o By product domain using CPA (Statistical classification of products by

activity)

o By work context using the work location ("Arbeitsorte") in the

Kompetenzklassifikation

• Contextualisation: analysis of how transversal skills, competences or knowledge

are applied in the specific context of a sector or an occupation.

4.3. Assign the ESCO skills to each approach

The ESCO team assigned the skills to NACE, DISCO and Kompetenzklassifikation

manually using spreadsheet dataset per classification:

a spreadsheet listing the ESCO skills sample and

a spreadsheet listing metadata of the external classifications.

Using the information in these files the team assigned each ESCO skill from the sample

to a related concept (or multiple concepts in case of NACE) in the external

classifications. The relations were established using machine-readable fields, e.g. concept

IDs) to enable loading into the testing application.

With respect to the approaches of grouping skills using other domains as

structures/collections and the contextualisation, a different methodology was used.

14 DISCO is a structured vocabulary for the description of skills and competences in different contexts. Its development

was co-financed by the Commission. The top level of DISCO is divided into domain-specific skills and non-domain

specific skills. http://disco-tools.eu/disco2_portal/

15 Kompetenzklassifikation lists occupations and professional activities in various labour market and socio-economic

contexts.

https://berufenet.arbeitsagentur.de/berufenet/faces/index;BERUFENETJSESSIONID=4EZ16arPZ9VHK8807Z7DihYjl

2Uv_swUl5TI619mlkATWaxzAITQ!-132602081?path=null

16 NACE classifies economic activities in the EU. It is organised in 21 sections and indicates 4-digit codes common to

all European countries. http://ec.europa.eu/eurostat/statistics-

explained/index.php/Glossary:Statistical_classification_of_economic_activities_in_the_European_Community_(NACE

)


https://berufenet.arbeitsagentur.de/berufenet/faces/index;BERUFENETJSESSIONID=4EZ16arPZ9VHK8807Z7DihYjl2Uv_swUl5TI619mlkATWaxzAITQ!-132602081?path=null

https://berufenet.arbeitsagentur.de/berufenet/faces/index;BERUFENETJSESSIONID=4EZ16arPZ9VHK8807Z7DihYjl2Uv_swUl5TI619mlkATWaxzAITQ!-132602081?path=null

http://ec.europa.eu/eurostat/statistics-explained/index.php/Glossary:Statistical_classification_of_economic_activities_in_the_European_Community_(NACE)




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This is described in sections 5.2 Other domains as the structure and 5.3

Contextualisation.

4.4. Test the approaches

In order to test how the different structuring approaches, perform in real-life situations,

the ESCO team analysed each one of them on a set of predefined use-cases via a web-

based testing application. These are the following:

• Find a concept in the classification

• Select groups of concepts for a specific action

• The system suggests related concepts

4.4.1. Testing application

The project team developed a test application to test the skills structures.

The application displays the following two screens:

1. Search screen:

Figure 5: a Search screen

The search screen allows the user to look for a specific skill from the sample using a

search engine [1] identical to the one on the ESCO portal. The results are listed under [2]

“Text match”.

The user can further narrow down these results using filters [3] which are populated by

three of the structuring approaches we are testing, i.e. NACE, DISCO and NSC (National

Skills Classification17). For an overview of the structuring approaches, please see 4.2

Select the structuring approaches. This should, in theory, enable the user to identify the

17 In this case the NSC we are testing is Kompetenzklassifikation (the skills classification used by the German PES).

1

2 3 4

https://ec.europa.eu/esco/portal/skill


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skill s/he is looking for in a more accurate manner compared to browsing through the

full-text results [1].

Furthermore, the right panel of the application “Contextualisation/Collections” [4]

supports the search by providing additional skills the user might be interested in. These

were not identified directly using search keywords [1].

2. Skills picker screen:

Figure 6: Skills suggestion screen - select an occupation

1

6 2


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Figure 7: Skills suggestion screen - evaluate skills

The skills picker screen enables users to receive suggestions of skills which might be

relevant for their profiles based on occupations they select. The user first selects one or

more occupations [1] and the structuring approach they want to test [2]. Based on this

input, the application suggests various skills to the user. The user may accept or reject [3]

each one of the skills depending on whether they match her/his profile.

As the user accepts/rejects skills, the algorithm adjusts further suggested skills based on

the selected structuring approaches [2]. The skills which the user already accepted are

listed in the left-hand field “Accepted skills” [4] and further suggestions alongside their

evolving score are listed in the right-hand field “Top suggestions” [5].

The user may also switch the suggestion mode to “Broader concepts” [6]. This allows

her/him receive suggestions from a list of concepts stemming from NACE or the National

Skills Classification (in this case Kompetenzklassifikation) instead of those stemming

from the ESCO skills pillar.

4.4.2. Testing approach

Each screen of the application using the following methodologies:

Testing of “search screen”: The ESCO team searched for skills coming from a job

vacancy and a CV (randomly chosen) using the search and filtering mechanism of

the testing application. Then they filled in a short questionnaire on the usefulness

of each one of the different structuring processes.

Testing of “skills picker screen”: The ESCO team extracted the skills from a job

vacancy and a CV (randomly chosen). Using the skills picker application, the

team accepted those skills which were part of the identified set and rejected the

3

4 5

2


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others. The team evaluated the quality of the suggestions based on (1) the number

of skills assessed, (2) the number of skills identified and (3) the number of

rejected skills.

5. Results and lessons learnt

5.1. Skills hierarchy

The results of structuring skills with the hierarchy of Kompetenzklassifikation and

DISCO are similar since both classifications i) follow a similar approach to structuring

skill concepts, ii) use a hierarchical grouping of concepts and iii) use sectors of economic

activity to structure sector-specific skills.

Neither contains detailed descriptions of their skill groups that could clarify their scope,

which makes it difficult to assign ESCO skills to the respective groups. Furthermore, both

classifications use economic sectors to classify domain-specific skills. Due to this, they

cannot be easily used as a mono-hierarchical structure, where each skill fits exactly in one

skill group. Certain ESCO skills could be assigned to more than one skill group as they

are not mutually exclusive.

While DISCO provides a breakdown of non-domain specific skills,

Kompetenzklassifikation has only one group. DISCO is available in 15 EU languages,

Kompetenzklassifikation only in German.

The effort required to maintain skills hierarchy based on existing classifications (DISCO

and Kompetenzklassifikation) is low since their structuring approach is built specifically

for the context of skills.

5.2. Other domains as the structure

Another approach to structuring skills is by expressing how they relate to other types of

concepts. This can be particularly useful for filtered search. The existing relationship

between skills and occupations in ESCO is of this type: it expresses which skills are

normally relevant in the context of an occupation and thus allows the user to filter the

skills pillar by occupation.

Following desk research, the ESCO team selected and tested four domains in the pilot

project: Economic activities (NACE), fields of education and training (ISCED-F),

product domain (CPA), Work context (Kompetenzklassifikation).

The effort required to maintain skill structure based on other domains listed here is

average since their structuring approaches are not built specifically for the context of

skills. On the other hand, most of the classifications (NACE, ISCED-F, CPA) contain

exhaustive descriptions of concepts which are very helpful when identifying the correct

concept for each relation.

5.2.1. NACE

The ESCO team assigned the ESCO skills to the relevant NACE groups of economic

activities. The relation of ESCO skills to NACE group mean that tasks enabled by the

skill are performed in scope the specific sectors of economic activity. This would allow

users to filter on skills that typically contribute to a specific economic activity. “Load

animals for transportation” could, for example, be a skill relevant among others in the

economic activities “freight transport by road” and “animal production”.


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As NACE is a hierarchical four-level structure, skills can be assigned to economic sectors

at different granularity levels. In the pilot, several transversal skills were assigned to all

NACE sections since they apply to all sectors of economic activity. There was hardly any

ESCO skill that could be related to only one single NACE section.

The definitions of the NACE sections and the indications of the scope of the section are

very useful to delimit the scope and be accurate in assigning skills.

5.2.2. ISCED-F

The ESCO team assigned skills to the domains of education and training. The relation of

OSCO skill to specific ISCO-F code indicates where these skills are usually taught.

“Load animals for transportation” could, for example, be a skill taught in education and

training programs in the field of “transport services” or “crop and livestock production”.

At the lowest level, ISCED-F 2013 contains 80 detailed fields. The results showed that

the ISCED-F classification is valuable and would be particularly useful when annotating

learning outcome descriptions.

5.2.3. Statistical Classification of Products by Activity

The Statistical Classification of Products by Activity (CPA)18 lists services and products

in 3,218 subcategories. The relation of ESCO skills to CPA group mean that tasks

enabled by the skill produce, provide or utilise given product of CPA. It proved difficult

to decide on the appropriate relation to skills. It could, for example, express that

knowledge of a certain product or service category is useful for developing a skill. For

example, knowledge of “road transport services of live animals” or of “dairy cattle, live”

is useful for developing the skill “load animals for transportation”.

5.2.4. Work Context

The Kompetenzklassifikation work context classification is limited to 156 concepts

which is a small number to assign to 13,485 ESCO skills, whereas it is usually not

possible to assign a skill to a single work context. The relation of ESCO skills to work

context means that tasks enabled by the skill are performed in the location indicated by

the work context. Skills are usually performed in a range of different locations. For

example, the skill “load animals for transportation” can among others be performed at a

"harbour/wharf", an "animal hospital" or at an "animal enclosure".

5.3. Contextualisation

Skill contextualisation is a method to create knowledge or skill and competence concepts

by analysing how transversal skills, competences or knowledge are applied in the specific

context of a sector or an occupation. This allows bringing transversal knowledge, skills

and competences which are rather abstract to a more detailed level so that they can be

directly used in occupational profiles.

Contextualisation can be implemented through different relations that are part of the

ESCO data model. These are:

Broader/narrower relation (=hierarchical relation)

18 http://ec.europa.eu/eurostat/statistics-

explained/index.php/Glossary:Statistical_classification_of_products_by_activity_(CPA)

http://ec.europa.eu/eurostat/statistics-explained/index.php/Glossary:Statistical_classification_of_products_by_activity_(CPA)

http://ec.europa.eu/eurostat/statistics-explained/index.php/Glossary:Statistical_classification_of_products_by_activity_(CPA)


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“Essential for” relations (=associative relation)

“Optional for” relations (=associative relation)

These types of relations can be established if the description of the skills is clear enough

to define its content and scope. The approach was used when developing ESCO v1, but it

has not been applied consistently over the entire skills pillar. Therefore, the ESCO team

proposes a set of rules for improving the skills descriptions. This will allow creating more

precise and consistent relations.

The effort required to maintain contextualisation structure is high since it requires a

detailed evaluation of each ESCO skill and (potentially) their relation to all other skills in

the classification.

5.3.1. Current status

Currently, 9,618 skills (71.3%) have at least one relation to another skill. In the figure

below, you can see a breakdown of skills per number of their relations.

Figure 8: Breakdown of ESCO skills with contextualisation

36

72

2

23

5

13

76

9

34

5

18

2

85

2

05

1

13

6

2

63

3

6

21

1

5

7 9

5

5

6

4

1

5

3

2

3

1

1

1

1

3

2

1

1

1

1

2

1

1

2

2

1

1

1

1

1

1

1

1

1

1

1

1

1

10

100

1000

10000

1

3

5

7

9

11

13

15

17

19

21

23

26

29

32

34

38

43

49

58

61

76

11

6

12

6

19

8

27

7

NU

MB

ER O

F K

SC

NUMBER OF RELATIONS

NUMBER OF KSC WHICH HAVE CERTAIN # OF RELATIONS


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5.3.2. Proposed rules for contextualisation

5.3.2.1. Definition of terms

Skill features

• Skill features represent distinct parts that a skill should contain. These are:

• Action [A]: an action performed within the scope of a concept

• Subject [S]: the subject of the action which is performed

• Context [C]: the context in which the action is performed

Example:

work in metal manufacture teams – A: Work; S: In teams; C: metal manufacture

evaluate information – A: Evaluate; S: Information

plan weapon use on stage – A: plan; S: weapon use; C: on stage

advise on poisoning incidents – A: advise on; S: incidents; C: poisoning

Skill A is Broader (BT) to Skill B – Skill B is Narrower (NT) to Skill A

• Skill B represents a specialisation and/or a part of Skill A

• Skill A is more general in all of its features (Action/Subject/Context) to Skill B

In the following examples, we mark with red colour those relations which refer to an

incorrect case, something that should be prevented in the classification. We mark with

green colour the correct ones.

Example: manage data -- BT --> gather data

Explanation: “gathering” is a part of “management”, therefore the relationship is

established correctly

Skill A is Essential (ESS) for Skill B:

• Skill A is required in order to carry out Skill B

• Not possible to establish if a hierarchical relation already exists, e.g. "Skill A is

Broader to a Skill B".

Skill A is Optional (OPT) for Skill B:

• Depending on the context, Skill A may be required or be beneficial in order to

carry out Skill B

• Not possible to establish if a hierarchical relation already exists, e.g. "Skill A is

Broader to a Skill B".


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5.3.2.2. Proposed general rules

The concepts have to be analysed holistically, the analysis should not be solely based on

the preferred term of the concept.

Example:

collection management -/- BT -/-> collection management software

Explanation: The subject of the first skill is a process and of the second a software, since

the subject is different the relationship cannot be established

manage data -/- BT -/-> manage data collection systems

Explanation: The subject of the first skill is a data/database, and a method/strategy for

the second one since the subject is different the relation cannot be established

In case a hierarchical relationship already exists, it takes priority over the associative

relation.

Example:

write work-related reports -- BT --> write stress analysis reports

write work-related reports -/- ESS for -/-> write stress analysis reports

Explanation: The first line establishes a hierarchical relationship, which has priority

over the second line, rendering the second incorrect

5.3.2.3. Proposed rules for the hierarchy

In order to establish a hierarchical relation between two skills, each action, subject and

context of the narrower skill must be the same or narrower than that of the broader (or be

absent).

Broader skill

Narrower skill

Action

Action

Subject

Subject

Context

Context

Each feature should be evaluated and only if all of them follow the aforementioned rule, a

BT/NT relation can be established.

Example: create production schedules -/- BT -/-> adjust the production schedule

Explanation: The action of the first skill is to set up the initial schedule, while the action

of the other one is to adjust it. Therefore, a BT/NT relationship cannot be established.


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In case a feature is missing in a skill, this skill acts as “the broader”.

Example: order products -- BT --> place orders for orthopaedic products

Explanation: The context of the broader skill is missing, therefore the concept is

correctly considered broader

Hierarchical relations can be established only from skills with higher reusability level19 to

lower or the same not vice versa:

1. Transversal (highest)

2. Cross-sectoral

3. Sector-specific

4. Occupation-specific (lowest)

Example: manage data -/- BT -/-> manage quantitative data

Explanation: “manage data” is a sector-specific skill, while “manage quantitative data”

is a transversal skill. A transversal skill cannot be narrower to a sector-specific skill,

therefore this relation is incorrect

A skill20 and a knowledge21 cannot be related hierarchically.

Example: orthopaedics -/- BT -/-> sell orthopaedic goods

Explanation: orthopaedics is knowledge concept, therefore it cannot be established as

broader

5.3.2.4. Proposed rules for associative relations

The relation ESS for can be established only if the context of the two skills is identical.

Example: animal welfare -- ESS for --> promote animal welfare

Explanation: “animal” context is identical between both skills, therefore the relationship

is correct

19 https://ec.europa.eu/esco/portal/escopedia/Skill_reusability_level

20 https://ec.europa.eu/esco/portal/escopedia/Skill

21 https://ec.europa.eu/esco/portal/escopedia/Knowledge

https://ec.europa.eu/esco/portal/escopedia/Skill_reusability_level

https://ec.europa.eu/esco/portal/escopedia/Skill

https://ec.europa.eu/esco/portal/escopedia/Knowledge


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The relation OPT for should be established if all other relations are ruled out.

Example: food homogenisation -- OPT for --> interpret data in food manufacturing

Explanation: no other relationship could be established between these two concepts,

therefore OPT relation is correct.

Associative relations can be established only from skills with higher reusability level to

lower or the same not vice versa.

Example: components of clocks -/- ESS for -/-> maintain clocks

Explanation: “maintain clocks” is cross-sectoral skill while “components of clocks” is a

sector-specific skill. A sector-specific skill cannot be essential for a cross-sectoral skill.

A skill and a knowledge cannot be related associatively.

Example: speak different languages -/- ESS for -/-> foreign languages for international

careers

Explanation: “speak different languages” is knowledge concept, therefore it cannot be

established as ESS for skill concept

5.3.3. Identification of potential skills for contextualization

In order to streamline the identification of potential hierarchical and associative relations,

the ESCO team could develop a system which would suggest relevant skills based on:

• their co-occurrence in occupations;

• text similarity in all languages;

• co-occurrence in groups of external hierarchies and

• data from EURES users on the skills they use in job vacancies and CVs (future).

Such a system would be based on an algorithm supporting the mapping platform22 or

skills picker and could be installed as a module of ESCO taxonomy management service

(or another ESCO maintenance service). It is recommended to use such tool once the

structure of the skills pillar is improved.

22 Mapping platform is a central European IT platform that allows Member States to create, update, manage

different versions of mappings and publish correspondence tables (mappings) - free of charge. In short, the

platform serves as an enabling infrastructure to map other classifications to ESCO. It allows to manually

map the concepts from one classification to concepts of another classification. It is supported by advanced

search options, automatic mapping suggestions and user-friendly interface.


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6. Recommendations

Following the results of the pilot, the ESCO team recommends further exploring the use

of ISCED-F and NACE as external classifications to structure ESCO.

Contextualisation is a useful approach since it provides clear relations among skill

concepts. It can be used for various purposes and the skills pillar is already annotated

with such relations. Furthermore, revising the contextualisation and the methodological

rules related to it would improve the consistency of the skill pillar. On the other hand, it

requires a high effort to manually maintain such relations due to a high number of

concepts in the skills pillar.

DISCO and Kompetenzklassifikation, the two hierarchical skills classifications

evaluated within the scope of this project, use sectors of economic activity to structure

skills. Sectors of economic activity are not suitable as a base for a hierarchical

arrangement of concepts in which each concept can have only one broader concept

(mono-hierarchy), which is the hierarchical arrangement of interest in the case of ESCO,

because a single skill can inherently be related to several different sectors of economic

activity.

6.1. Possible further testing

The ESCO team identified further approaches for testing to improve the structure of the

skills pillar. These are the following:

Machine-learning structure: develop a structure based on the co-occurrence of

skills in various documents on the web. This could be achieved once the

Commission services receive data input from partners who use ESCO, e.g.

EURES, Cedefop, etc.

Collections based on common words: common words could be used to group

skills, e.g. a collection named “management” could be composed of all skills that

contain the word “manage” in their terms or description.


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6.2. Implementation into full ESCO

Implementation of each structuring approaches will require various effort indicated, as

indicated in each of the detailed sections (c.f. Results and lessons learnt). The process of

structuring can be supported by software tools for semantic alignments, such as the

ESCO mapping platform.

6.3. Maintenance in full ESCO

Maintenance may consist of several different aspects:

Update during the release of new version of ESCO

Update during the release of new version of an external classification used for

structuring

Update for correction purposes

6.3.1. Update during the release of new version of ESCO

Such update is inherent in the maintenance cycle of ESCO and has to be performed

accordingly. On the other hand, it can be expected that not all skills will require a new

structure assignment, it is required to only update skills which were impacted (added or

modified) in the scope of the new release.

6.3.2. Update during the release of new version of an external classification

In case an external classification used for structuring (e.g. NACE) is updated the ESCO

relations to it should be updated as well. The urgency of such update will be directed by

the adoption rate of the new version of the external classification. The update can also be

supported using conversion tables provided by the maintainers of the external

classification. Such conversion tables commonly list the concepts which were impacted

and how they relate to concepts in the former version.

6.3.3. Update for correction purposes

Identifying skills or attempting to correct problems in the full dataset of 13.485 skills can

be time-consuming and inefficient. Concentrating search and correction efforts to subsets

of the full skills list can make maintenance more efficient.

For example: following technological developments in the logistics domain, a Member

State identifies that some ESCO skills are missing their relation to NACE 5210:

Warehousing and storage. The Member State provides such feedback to the EC who

proceeds with a review of structuring in the logistics domain.

7. Open issues

The main pending issue identified during the pilot is the lack of an existing suitable

mono-hierarchy that could be used for statistical labour market data purposes. This could

be the default browsing mechanism of the skills pillar. Such classification would have to

be composed of skill groups which are mutually exclusive, i.e. a single skill can be placed

only in a single group, thanks to clear scoping of groups. For the ESCO occupational

pillar, ISCO serves as such a mono-hierarchical structure.


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In case a mono-hierarchy of skills would be the most suitable structure to address the user

needs which are reflected in the use case examples, it would be necessary to build a

custom solution for the purposes of ESCO.

Documents

DLV011 Summary report on ESCO skills pillar pilot...DLV011 – Summary report on ESCO skills pillar pilot Results and lessons learnt 4 of 28 Skills hierarchy The results of structuring