Modelling Inventory and Knowledge Management System of the European Commission (MIDAS) : opening to the public and recent developments.
Date: 2021-12-06
Institutions: Joint Research Centre
Subjects: European Commission, Internet site, database, impact study, information security, information system, knowledge management, metadata, performance measurement, policymaking, regulatory policy, report, scientific press

Modelling Inventory and Knowledge 
Management System of the European 
Commission (MIDAS) 

Opening to the public and 
recent developments 

 Hardy, M., Listorti, G., Basyte Ferrari, E., 
Ostlaender, N., Delabaere, T. 

2021 

EUR 30903 EN

 
 
This publication is a Scientific Information Systems and Databases report by the Joint Research Centre (JRC), the European Commission’s 
science and knowledge service. It aims to provide evidence-based scientific support to the European policymaking process. The scientific 
output expressed does not imply a policy position of the European Commission. Neither the European Commission nor any person acting 
on behalf of the Commission is responsible for the use that might be made of this publication. For information on the methodology and 
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contact the referenced source. The designations employed and the presentation of material on the maps do not imply the expression of 
any opinion whatsoever on the part of the European Union concerning the legal status of any country, territory, city or area or of its 
authorities, or concerning the delimitation of its frontiers or boundaries. 

EU Science Hub 
https://ec.europa.eu/jrc 

JRC127078 

EUR 30903 EN 

PDF 

ISBN 978-92-76-44453-4 

ISSN 1831-9424 

doi:10.2760/909559 

Luxembourg: Publications Office of the European Union, 2021 

© European Union, 2021 

The reuse policy of the European Commission is implemented by the Commission Decision 2011/833/EU of 12 December 2011 on the 
reuse of Commission documents (OJ L 330, 14.12.2011, p. 39). Except otherwise noted, the reuse of this document is authorised under 
the Creative Commons Attribution 4.0 International (CC BY 4.0) licence (https://creativecommons.org/licenses/by/4.0/). This means that 
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All content © European Union, 2021 

How to cite this report: Hardy, M., Listorti, G., Basyte Ferrari, E., Ostlaender, N. and Delabaere, T., Modelling Inventory and Knowledge 
Management System of the European Commission (MIDAS), EUR 30903 EN, Publications Office of the European Union, Luxembourg, 
2021, ISBN 978-92-76-44453-4, doi:10.2760/909559, JRC127078. 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Contents 

Foreword ..................................................................................................................................................................................................................................................................... 1 

Acknowledgements .......................................................................................................................................................................................................................................... 2 

Abstract ....................................................................................................................................................................................................................................................................... 3 

1 

Introduction..................................................................................................................................................................................................................................................... 4 

2  The MIDAS opening to the public: contributing to transparency for Better Regulation ......................................................... 6 

2.1  Transparent evidence-informed policy support for Better Regulation ..................................................................................... 6 

2.2  The opening of MIDAS to the public .......................................................................................................................................................................... 7 

3  Developments in MIDAS contents and user requirements ................................................................................................................................ 8 

3.1  The Contents of MIDAS .......................................................................................................................................................................................................... 8 

3.2  The evolution of the user requirements: the three MIDAS versions ........................................................................................ 10 

4  Evolution of the MIDAS infrastructure ............................................................................................................................................................................... 12 

4.1  Release process ......................................................................................................................................................................................................................... 12 

4.2  Security .............................................................................................................................................................................................................................................. 12 

4.3  Performance .................................................................................................................................................................................................................................. 13 

4.4  Editor .................................................................................................................................................................................................................................................... 14 

5  Functionality ............................................................................................................................................................................................................................................... 15 

5.1  Fact Sheets ..................................................................................................................................................................................................................................... 15 

5.2  Search.................................................................................................................................................................................................................................................. 17 

5.3  Explore ................................................................................................................................................................................................................................................ 17 

5.4  Application programming interface ........................................................................................................................................................................ 18 

5.5  Publications .................................................................................................................................................................................................................................... 19 

6  Technical architecture........................................................................................................................................................................................................................ 20 

6.1  Service-oriented architecture........................................................................................................................................................................................ 21 

7  Conclusions .................................................................................................................................................................................................................................................. 22 

References ............................................................................................................................................................................................................................................................. 23 

List of abbreviations and definitions ........................................................................................................................................................................................... 24 

List of figures ..................................................................................................................................................................................................................................................... 25 

Annexes .................................................................................................................................................................................................................................................................... 26 

Annex 1. MIDAS Public model description ...................................................................................................................................................................... 26 

i 

 
 
 
 
 
 
Foreword 

Developed  and  managed  by  the  European  Commission’s  Competence  Centre  on  Modelling,  the  Modelling 
Inventory  and  Knowledge  Management  System  of  the  Commission  (MIDAS)  has  evolved  over  time  from  a 
simple list of models to an entire information system designed to help collect, store and distribute metadata 
of models used by the Commission in support of the policy cycle.  

MIDAS provides direct support to the Commission’s Better Regulation policy (BR). In 2020, it has been opened 
to the public as part of the BR commitment to transparency of evidence used in the EU policymaking.  

Over  the  past  years,  the  audience  and  priorities  of,  and  requirements  for  MIDAS  have  all  evolved  and  the 
technical infrastructure has accordingly developed to reflect that. This paper is an attempt to document this 
experience. The information provided complements and updates the JRC Technical Report on MIDAS published 
in 2019 (Ostlaender et al. (2019). 

1 

 
 
 
Acknowledgements 

MIDAS  is  a  Commission-wide  activity  that  is  only  made  possible  thanks  to  the  inputs  from  the  European 
Commission’s Community of Practice (CoP) on Modelling and members of the Interservice Group on Modelling. 
It is important, therefore, to recognise the contribution of the Commission’s modellers, model users in all the 
departments (Directorates-General) as well as external contractors for providing the model descriptions that 
are the central part of the MIDAS knowledge base. At the end of the day, the MIDAS information system will 
only ever be as good as its content. 

Authors 

Matthew Hardy, Giulia Listorti, Egle Basyte Ferrari, Nicole Ostlaender, Thieffen Delabaere 

2 

 
 
Abstract 

MIDAS  is  a  scientific  information  system  developed  and  managed  by  the  Competence  Centre  on  Modelling 
(CC-MOD)  of  the  Joint  Research  Centre  (JRC)  of  the  European  Commission.  In  the  framework  of  the  Better 
Regulation policy, MIDAS directly contributes to the Commission’s commitment to transparent evidence-based 
policy support. 

First developed in 2013 and rolled out to the entire Commission in 2017, MIDAS includes information about 
the  models  used  to  support  the  policy  cycle.  Since  2017,  the  Better  Regulation  Guidelines  and  Toolbox 
(European Commission 2017) strongly recommends that models  used in Commission’s impact assessments 
are  described  in  MIDAS.  In  2019,  MIDAS  was  made  accessible  to  the  European  Parliament  to  support  the 
analysis of the Commission’s policy proposals. MIDAS was opened to the public in 2020. This step aimed at 
helping stakeholders and the society at large to understand the Commission’s work on impact assessments, 
as stated in the 2021 BR Communication (European Commission 2021). Therefore, over the past two years, 
MIDAS has had to undergo some transformations to adapt to changing requirements. In parallel, its technical 
infrastructure has developed to reflect these changes.  

The purpose of this document is thus twofold: on the one side, to report how the MIDAS opening to the public 
contributed to the Better Regulation policy; on the other, to provide an up-to-date description of the technical 
architecture  and  functionality,  complementing  and  updating  the  information  included  in  the  MIDAS  JRC 
technical report published in 2019. 

3 

  
 
1 

Introduction 

The  Modelling  Inventory  and  Knowledge  Management  System  of  the  Commission  (MIDAS)  is  a  scientific 
information  system  developed  and  managed  by  the  Competence  Centre  on  Modelling  (CC-MOD)1  of  the 
European  Commission  (Commission  thereafter)  to  document  the  models  run  by  or  on  behalf  of  the 
Commission and their contributions to Commission’s impact assessments. MIDAS provides an integrated set 
of  components  for  collecting,  storing,  processing  and  sharing  metadata  on  model  structure,  quality  and 
transparency, as well as access to model documentation, useful references and the supported Commission’s 
impact assessments. 

The use of models has become increasingly important to support EU policymaking. Models are used 
across  the  whole  policy  cycle  and  many  different  policy  fields,  such  as  agriculture,  climate,  environment, 
transport, economics and fisheries.  In impact assessments, they  are  used  to  determine baseline  scenario(s) 
and  assess  the  environmental,  economic,  and  social  impacts  of  the  proposed  policy  options.  16%  of  all 
Commission impact assessments carried out in the years 2003-2018 were supported by models, growing to 
25-30% of impact assessments in 2015-20182. From 2019 to 2021, the share of IAs using models increased 
to 46%3. 

The main purpose of MIDAS is to enhance the transparency of policy-relevant models and the traceability of 
their use, as well as facilitating the understanding of impact assessments performed by the Commission. This 
is  in  accordance  with  what  is  requested  by  the  Better  Regulation  (BR)  policy4  to  which  CC-MOD  directly 
contributes  by  promoting  a  responsible,  coherent  and  transparent  use  of  modelling  that  underpins  the 
evidence base of EU policies. 

MIDAS  can currently be accessed  at  European  Commission,  Inter-Institutional  (European  Parliament 
(EP) and  Council) and public level5, which provide  different levels of access to the underlying  knowledge 
base (details see section 3.2). This follows the evolution of its main developments in role and audience over 
time, which can be summarised as follows6: 

 

 

 

In  2013,  MIDAS  started  as  a  JRC-internal  initiative  to  European  Commission  (2017)  enhance 
transparency of scientific models that directly or indirectly support the policy process7. 
In 2017, MIDAS was launched as a Commission’s corporate tool, following a recommendation of 
the Commission’s High Level Reflection Group on information management. 
Since 2017, the BR Toolbox accompanying the BR Guidelines8 states that models used for impact 
assessments should be described in MIDAS. 

  As of 2019, MIDAS has been opened to the European Parliamentary Research Service (EPRS)9 of 
the  European  Parliament  in  the  context  of  the  Inter-Institutional  agreement  on  Better  Law-
Making10, and subsequently to the Council of the European Union. 

1 CC-MOD webpage: https://knowledge4policy.ec.europa.eu/modelling/about_en  
2 Source: Acs et al. (2019). 
3  Own  calculation  based  on  the  comparison  between  the  MIDAS  data  and  the  total  number  of  IA  reports 

published in 2019-2021, available in the Register of Commission Documents on 2021.10.25. 

4  More  about  the  Better  Regulation  framework  can  be  found  in  the  next  chapter.  Also  see  the  dedicated 

webpage, Better Regulation Guidelines (SWD (2017) 350) and associated Toolbox. 

5 MIDAS can be accessed at the following links:  

—  internal access for European Commission services: http://midas.jrc.cec.eu.int/ 
—  inter-institutional 

version  accessible 

the  European  Parliament  and 

to 

the  Council: 

https://webgate.ec.testa.eu/midas-ii   

—  public: https://web.jrc.ec.europa.eu/policy-model-inventory/  

6  For  a  comprehensive  overview  on  the  beginnings  of  MIDAS,  objectives  and  background  of  CC-MOD  see 

Ostlaender et al. (2019) 

7 Ostlaender et al. (2015)  
8 European Commission (2017) 
9  In  this  respect,  the  EPRS  study  ‘Appraising  the  quality  of  the  European  Commission's  impact  assessments 
Trends and developments from 2015 to 2018’ (European Parliamentary Research Service 2019), states: “A 
very positive step in this context, with a view to fostering transparency and interinstitutional cooperation, is 
the  launch  of  the  Competence  Centre  on  Modelling  and  of  the  modelling  inventory  'MIDAS'  within  the 
Commission's  Joint  Research  Centre  in  2017  and,  last  but  not  least,  EPRS  access  to  an  interinstitutional 
version of MIDAS (Midas II) since 2019”. 

4 

 
 
 
                                           
 

In  2020,  the  MIDAS  public  website  was  released.  This  opening  to  the  public  is  in  line  with  the 
Better Regulation policy as well as the commitment to proactive document sharing according to 
Regulation 1049/2001 and Decision 2011/833/EU. 

Over this period, MIDAS has acquired new audiences, each one with its own set of priorities and requirements. 
The increasing MIDAS  role in terms of being instrumental for the  BR policy implementation implied  shifting 
the focus of the project from being model-centric to the support models provide to the Commission’s impact 
assessments. This evolution, as well as feedback from users of the MIDAS websites, such as the EPRS, were 
the main reasons for changing the technology  behind the components of MIDAS. At the same time, further 
architectural  needs  were also identified such as to improve performance,  avoid  technical  debt and  simplify 
the release process. 

This  publication  aims  at  providing  a  comprehensive  overview  of  the  latest  developments  in  the 
MIDAS project, explaining why these changes prompted a change to the technology behind MIDAS and how 
that technology changed. At the same time, this report will also provide an up to date description of MIDAS 
technical architecture and functionality. 

The document is structured as follows: we start by documenting the most recent contribution of MIDAS to BR, 
namely  its  opening  to  the  public  (section  2).  After  recalling  briefly  MIDAS  contents,  we  then  move  to 
describing how user requirements have evolved in recent years (section 3). The following section is dedicated 
to explaining the corresponding evolution of MIDAS release process, security, performance and editor (section 
4). We finally provide a complete overview of current functionality (section 5) and tech architecture (section 
6). We end with concluding remarks (section 7). 

10 European Parliament (2016). 

5 

 
 
 
 
                                                                                                                                    
2  The MIDAS opening to the public: contributing to transparency for 

Better Regulation  

2.1  Transparent evidence-informed policy support for Better Regulation 

The European Commission is committed to making policy decisions informed by sound, open and transparent 
evidence.  The  Commission's  approach  to  Better  Regulation  (BR)  is  characterised  by  a  series  of  principles, 
procedures,  requirements  and  recommendations  to  be  followed  when  EU  policies  and  laws  are  being 
designed, monitored and evaluated, with the aim to make simpler and better EU laws, backed by transparent 
evidence and views of citizens, businesses and stakeholders.  

Since the early 2000s, in line with the worldwide trends11, the Commission has been developing its regulatory 
framework  which  in  2015  took  the  name  of  BR  Agenda  (European  Commission  2015).  The  latest 
Communication  on  BR  (European  Commission  2021)  states  a  number  of  further  improvements  to  address 
unprecedented challenges, as well as to tackle the issues identified in the 2019 assessment of the BR policy, 
the so called stocktaking exercise (European Commission 2019a and 2019b) . Concerning the contribution of 
BR to transparent evidence-based policymaking, one of the findings of the systematic literature review carried 
out in support of the stocktaking (Listorti, G. et al. (2019) and Listorti, G. et al. (2020)) was that while authors 
recognised the Agenda’s efforts to make EU policymaking transparent and accountable, they also underlined 
the need to improve transparency regarding understandability and accessibility of evidence and, in particular, 
input and raw output data, calculations and modelling.  

This is particularly relevant for impact assessments that are carried out in support of policy decisions, i.e. in 
the  policy  formulation  phase  of  the  policy  cycle.  Models  play  an  important  role  to  evaluate  the  economic, 
environmental and social impacts of the proposed policy options. Indeed, since 2015, the BR Toolbox requires 
that an impact assessment using modelling results provide a description of the models used in a dedicated 
annex of the impact assessment report. The 2017 edition of the BR toolbox strongly recommends that models 
used for impact assessments should be described in MIDAS. 

In  the  2021  BR  Communication  (European  Commission  (2021)),  the  Commission  further  strengthens  its 
pledge to improve access to information and documents contributing to evidence supporting EU policymaking. 
Transparency is described as ‘fundamental to ensuring that people can play an active part in the policymaking 
process  and  hold  the  EU  institutions  accountable  for  their  decisions’12.  In  this  framework,  the  2021 
Communication promotes the opening of MIDAS to the wider public as a concrete manifestation of 
the  Commission  commitment  to  transparency  for  Better  Regulation.  This  important  step  aims  at 
helping citizens  and  stakeholders to  understand  the Commission work  on impact assessments: ‘Opening  up 
scientific evidence to public scrutiny is also essential to strengthen public trust. We have already made MIDAS 
publicly  available,  so  that  anyone  interested  can  understand  the  methods  and  assumptions  used  in  our 
analysis’.13 

In addition to contributing to the Better Regulation policy, the opening of MIDAS to the public contributes to 
the  EU  commitment  to  transparency  and  openness  –  mostly  understood  as  access  to  information  and 
documents – introduced in the primary EU law already in the 1990s (Basyte Ferrari, E., et al. 2020). It is also 
in  line  with  the  concept  of  proactive  document  sharing  according  to  Regulation  1049/2001  (European 
Commission  (2001),  also  known  ‘access  to  documents  Regulation’)  and  Commission  Decision  2011/833/EU 
(European Commission (2011), ‘reuse Decision’). 

11 OECD (2018) OECD Regulatory Policy Outlook 2018 (Paris: OECD Publishing) 
12 p.7 European Commission (2021): ‘Better regulation: Joining forces to make better laws’ 
13 p.8 European Commission (2021): ‘Better regulation: Joining forces to make better laws’ 

6 

 
 
 
 
 
 
                                           
2.2  The opening of MIDAS to the public 

The opening of MIDAS to the public was implemented in December 2020, with the aim to help people better 
understand the evidence used by the Commission when designing policies, by facilitating communication and 
understanding of the underlying analyses14. 

Examples of questions that MIDAS can help answering are: 

  Which impact assessments have been supported by a specific model? 
  How many/which models contributed to a specific impact assessment? 
  Which models supported impact assessments in 2018? 
  Which models has a specific Commission policy department used in carrying out impact assessments 

of the European Commission? 

Initially, 14 Commission’s policy departments, known as Directorate-Generals (DGs), had been involved in the 
preparation of MIDAS public in 2020, under the lead of CC-MOD. This initial MIDAS public version included 35 
models  supporting  a  total  of  35  impact  assessments  published  as  of  July  2017,  in  accordance  with  what 
requested  by  the  BR  Toolbox.  At  the  time  of  writing  (October  2021)  MIDAS  public  includes  46  models 
supporting 54 impact assessments under the lead of 16 policy DGs.  

The opening of MIDAS to the public provided an opportunity for a wider discussion on the importance of sound 
and transparent evidence for policy in order to bring enhanced  understanding and confidence by the public, 
research bodies, and decision makers. Transparency in model use contributes to dissipating mistrust in model 
outputs, potentially leading to improvements both in modelling and in the policy process. Transparency is also 
key to bring enhancements to model quality.  

MIDAS public provides a concrete contribution to transparent evidence-informed policymaking in 
various respects. First and foremost, it promotes transparency in how models support impact assessments. 
In addition to facilitating communication and understanding of Commission’s analyses, this also strengthens 
confidence  in  the  contribution  of  models  to  provide  evidence  in  support  to  policymaking.  Secondly,  by 
encouraging  scrutiny  of  the  quality  of  evidence  provided15  as  well  as  the  exchange  of  good  practices  for 
better  model  quality,  MIDAS  also  contributes  to  robustness  and  legitimacy  of  the  evidence  that  the 
Commission uses to design policies. Finally, by making the information easy for the public to navigate, MIDAS 
public contributes to greater awareness by the public and, ultimately, better EU policymaking16. 

It should  be also noted that the opening of  MIDAS to the public has represented a fundamental shift in its 
audience and use. In a way, by linking the insertion of models in MIDAS public to their contribution to recent 
Commission’s impact assessments, the focus moved from an inventory of models to an inventory of 
impact assessments which are supported by models. This shift entails a number of challenges for the 
collection, update and maintenance of the information, which are described in the following sections.  

14 See also https://ec.europa.eu/jrc/en/news/public-launch-midas-discover-models-behind-eu-policies  
15 By e.g. enhancing access to the evidence underlying policymaking to enable peer review, which is strongly 
promoted  by  authors  such  as  Philip  Hines,  ‘Enlightening  EU  Policy-Making:  Evolving  Scientific  Advice’ 
(2016)  Policy  Brief,  European  Policy  Centre  <https://digital-strategy.ec.europa.eu/en/library/enlightening-
eu-policy-making-evolving-scientific-advice> (last accessed 8 November 2021). 

16 Improved transparency of the model used in policymaking addresses one of the challenges related to the 
better regulation implementation, as identified by some authors of the literature review in the context of the 
stocktaking of the Better Regulation Agenda, see Listorti, G., Basyte Ferrari, E., Acs, S., Munda, G., Rosenbaum, 
E., Paruolo, P. and Smits, P., The debate on the EU Better Regulation Agenda: a literature review, EUR 29691 
EN,  Publications  Office  of 
ISBN  978-92-76-00839-2, 
the  European  Union,  Luxembourg,  2019, 
doi:10.2760/407003,  JRC116035;  Basyte  Ferrari,  E.,  Rosenbaum,  E.,  Listorti,  G.,  &  Ostlaender,  N.  (2020) 
‘Opening  and  Improving  Policy  Development  to  Increase  Public  Trust:  Transparency  of  Evidence-based 
Regulation in the Debate on EU Better Regulation Agenda’, The Crisis of Confidence in Legislation, 169–196, 
doi: 10.5771/9783748907244-169. 

7 

 
 
 
 
 
 
                                           
3  Developments in MIDAS contents and user requirements  

3.1  The Contents of MIDAS 

MIDAS includes information on the following items17: 

  Models: models are computer-based stylized, quantified analytical representations of the real world 
that are used to make projections or to assess the behaviour of a system under specific (policy) 
assumptions. 
Impact assessments: in the Commission’s Better Regulation framework18, this term refers to an ex-
ante exercise to determine if future EU action is justified and how such action can best be designed 
to achieve desired policy objectives. The assessment is focused on expected economic, social or 
environmental impacts of a range of policy options. 

 

  Data: the datasets that models use or produce.  
  Studies: analytical exercises that use modelling results to answer policy relevant questions.  
  People: contact points for models or model runs. 

Given  its  central  role,  the  definition  of  what  is  a  model  in  the  MIDAS  framework  deserves  some  further 
reflection. This is particularly important following the opening to the public. 

It  should  be  noted  that,  across  the  various  disciplines,  the  term  model  can  refer  to  a  wide  array  of 
quantitative or qualitative tools or methods. From a reader’s perspective, it could be  argued that any entity 
referred to as a ‘model’ in the impact assessment report should be inserted in MIDAS. This approach would 
however  bring  risks  related  to  the  theoretical  consistency  of  the  inventory.  A  definition  of  what  should  be 
considered as a model in this context is thus needed.  

While  it  is  clear  that  no  definition  can  be  fully  comprehensive  and  exhaustive  given  the  high  variety  of 
disciplines involved, a pragmatic working definition has been defined based on input by the Commission’s 
Inter-Service Group on Modelling: ‘models are computer-based stylized, quantified analytical representations 
of the  real  world that are  used to make  projections  or  to assess the behaviour of  a  system  under specific 

(policy) assumptions.’ 

Based on this definition, a model is: 

- 
- 
- 

offering a representation of a real-world system; 
able to assess its behaviour under specific assumptions, including policy assumptions;  
computer-based. 

A model typically includes the following elements: 

- 
- 
- 
- 
- 
- 

inputs, i.e. underlying data; 
assumptions, which are represented as mathematical equations in programming language; 
outputs; 
a specific spatial and temporal extent; 
specific use to explore a policy question;  
the possibility to carry out uncertainty and sensitivity analysis. 

In  principle,  all  models  that  correspond  to  the  above-mentioned  definition,  contain  the  above-mentioned 
elements and are used in support of an IA should be inserted in MIDAS. Note that this is irrespective of single 
or repeated use in support of Commission’s IAs (also models used only once should be inserted in MIDAS), and 
complexity of the software used (model can in fact be based even on relatively simple software (such as a 
spreadsheet).   

In practice, the term ‘model’ can be used to refer to a variety of quantitative methods for empirical analysis, 
tools or methodologies. These might not qualify for insertion in MIDAS. This concerns, for example, what could 
be  indicated  as  a  ‘model’,  but  does  instead  refer  to  a  general  methodology  or  another  meaning,  such  as 

17 For a comprehensive description see Ostlaender et al. (2019). 
18 See also https://ec.europa.eu/info/law/law-making-process/planning-and-proposing-law/impact-

assessments_en  

8 

 
 
 
 
 
 
 
                                           
‘standard cost model’, ‘econometric model’, and so on. These tools are usually described directly in the text of 
the impact assessment report. 
After  confirming  its  eligibility  for  insertion  in  MIDAS,  we  distinguish  four  different  roles  (or  types  of 
contribution) that a model can play to support an impact assessment: 
1. supporting the problem definition; 
2. providing evidence in ex-post evaluation of relevant existing policies; 
3. providing evidence for the baseline used for the impact assessment; 
4. contributing to the assessment of the policy options19. 

All decisions on model insertion are discussed and agreed with the responsible policy DGs leading the impact 
assessment.  Note  that  model  contribution  can  be  directly  described  in  the  text  of  the  IA  report  or  in  a 
supporting study, which is then also inserted in MIDAS. 

The models and their contributions should always  be documented when models are used for the 
assessment of policy options (case 4), that is, they are mentioned in an IA report Annex 4, dedicated to the 
description  of  analytical  methods.  This  type  of  contribution  is  reported,  if  feasible,  according  to  the  impact 
areas,  impact  categories  and  guiding  questions  (impact  subcategories)  indicated  in  the  Better  Regulation 
Guidelines  and  Toolbox  (European  Commission  2017).  In  all  other  cases  (contribution  to  the  problem 
definition, ex-post evaluation and the construction of baselines), models and their contributions are inserted in 
MIDAS  wherever  relevant.  In  particular,  the  model  and  its  contribution  are  usually  included  if  the  model  is 
explicitly described in the Annex 4 as used for the baseline. 

A  special  case  occurs  if  a  model  is  mentioned  in  the  Annex  4  of  the  impact  assessment  report  for  having 
contributed to the establishment of the baseline, and the same model was run again in a separate modelling 
exercise for the assessment of policy options. This may be the case if the impact assessment is based on a 
reference scenario, such as the EU Reference Scenario 2020 (European Commission (EU Reference Scenario 
2020)). In this case, usually the model is included in MIDAS under the category 4, and a written reference is 
added  under  ‘additional  information’  indicating  that  the  IA  is  based  on  a  reference  scenario  including 
modelling. This allows a more consistent and transparent referencing of the EU reference scenarios.   

19 Note that this option in itself usually includes a ‘baseline run’, which is the ‘Business as usual” scenario. 

9 

 
 
 
 
 
                                           
3.2  The evolution of the user requirements: the three MIDAS versions 

While  all  MIDAS  access  levels  (Commission,  Inter-Institutional  and public)  make  use  of  the same 
underlying  database,  the  emergence  of  the  three  different  audiences  led  to  the  creation  of  different 
subsets of the content (models and impact assessment) as shown in Figure 1. 

Figure 1. MIDAS levels of accessibility 

The Commission-internal version of MIDAS contains all models developed or run by or on behalf of the 
Commission as of 2013 and all related information on data, studies and impact assessments. Personal data 
on  model  contact  points  are  also  included  to  the  Commission’s  version.  External  users  can  contact  EU-
MIDAS@ec.europa.eu for information.  

The MIDAS Inter-Institutional version only includes models that have contributed to impact assessments 
supported  by  models  as  of  2013,  to  support  the  work  carried  out  by  the  EP  and  the  Council  regarding  the 
analysis of Commission proposals.   

MIDAS public is a further subset of metadata and only includes impact assessments supported by models 
starting from July 2017, in accordance with what is recommended by the Better Regulation Toolbox.  

It  should  be  noted  that  the  three  MIDAS  versions  have  different  levels  of  visibility  of  the 
metadata. In addition to personal data, which as mentioned are only included in the Commission’s version, 
also  other  fields  (data,  relationship  with  other  models,  potential  impact  areas,  studies  not  contributing  to 
impact assessments, license details) are shown only in the Commission and Inter-Institutional versions.  

From a technical perspective, the three MIDAS versions were not developed using the same codebase but 
rather as separate websites based on similar code and components. This offered much needed flexibility as 
the websites started to diverge based on the different user communities and their respective requirements. 
Also,  during  the  development  of  each  new  version  of  MIDAS,  it  was  not  certain  for  how  long  each  version 
would  last  nor  exactly  what  the  final  requirements  would  be.  In  addition,  it  should  be  noted  that  the 
maintenance  and  regular  update  of  the  information  requires  a  consistent  investment  of  resources,  which 
should be targeted effectively according to the end use and added value they provide. 

The  Commission’s  version  of  the  MIDAS  website  remained  model-centric  and  aiming  at 
comprehensiveness, as its first main aim was to get as complete inventory as possible of all models used on 

10 

 
 
 
behalf or by the Commission throughout the policy cycle. The Inter-Institutional and public versions of 
MIDAS  became  much  more  impact  assessment-centric  (EPRS  much  more  likely  uses  an  impact 
assessment as a starting point in assessments) and concentrated thus on the quality and completeness of the 
information  provided,  though  only  for  models  used  for  impact  assessment.  The  Commission’s  version 
remained a rather specialist tool which in its design and choice of functionality considered primarily modellers 
and model users,  and thus assumed the  user  had  some  degree  of knowledge about  models. For the  public 
version, no such assumptions could be made and thus it became much simpler to understand and navigate as 
it had reduced functionality and more extensive explanation of concepts. 

This  left  CC-MOD  with  the  task  of  maintaining  three  websites  which  proved  a  complicated  and  time-
consuming commitment. Thus the need arose to design a website suitable for all three versions and to use 
the same codebase for each of them, so that changes and maintenance are performed in one place only.    

11 

 
 
 
4  Evolution of the MIDAS infrastructure 

The  driving  force  behind  most  of  the technology  change in MIDAS  has  been  the change in audience.  When 
MIDAS was first launched in 2013 as an inventory of models  run or used by the JRC, the main users were 
considered  being  modellers,  who  were  asked  to  describe  their  models  in  the  system.  With  its  extension  of 
models used in the entire Commission, models run or used by other DGs came in the picture, together with 
policymakers searching for and accessing these model descriptions. The MIDAS website was then extended to 
the  European  Parliament  in  2019  mainly  to  support  its  Research  Service  during  their  evaluation  of  impact 
assessments prepared by the Commission. This version is known as MIDAS-ii (MIDAS Inter-Institutional) as it 
was later also opened to the European Council. The release of a public version of MIDAS in 2020 as part of a 
commitment to transparency introduced non-specialist end users.  

Each  new  user  community  brought  with  them  their  own  requirements  and  priorities,  and  each  new  release 
environment  created  challenges to the system.  This chapter highlights  these issues  and  describes technical 
changes  made  to  address  them,  concerning  the  release  process  (section  4.1),  security  (section  4.2), 
performance (section 4.3) and editor (section 4.4) of the system. 

4.1  Release process 

The  original  MIDAS  websites  were  dynamic,  retrieving  content  through  PHP  scripts  communicating  with  a 
database,  and  therefore  required  an  online  database.  As  well  as  being  separate  websites,  as  already 
described in the previous section, the different versions also have different levels of content behind them (see 
section Error! Bookmark not defined. on content).  

When MIDAS was opened to the EP, this was controlled through the MySQL statements within the PHP scripts. 
For  the  public  website,  further  reducing  the  database  ensured  that  no  content  (such  as  personal  data  or 
information) was unintentionally released to the public version.  

As  a  consequence,  this  meant  that  different  databases  and  websites  had  to  be  released  for  the 
different  versions.  Complicating  this  further  is  the  fact  that  MIDAS  was  released  to  three  different 
environments: 

  MIDAS Commission: https://midas.jrc.cec.eu.int/discovery/midas/, an environment managed by the 

Joint Research Centre (DG JRC); 

  MIDAS Inter-Institutional: https://webgate.ec.testa.eu/midas-ii/, an environment managed by the 

European Commission Directorate-General Informatics (DG DIGIT); 

  MIDAS Public: https://web.jrc.ec.europa.eu/policy-model-inventory/, an environment managed by the 

JRC. 

For example, this lead to the inconvenience that the MySQL versions run by the JRC and DIGIT were not the 
same, so a SQL statement used to load a database to one environment may not execute on another. Further 
changes to the database structure were also occasionally required in order to be able to release.  

In  short,  it  became  clear  that  the  complexity  of  the  release  process  for  a  change  effecting  all  versions  of 
MIDAS grew with each new audience. 

As MIDAS is a system that will be continuously updated, it is of outmost important that it run on content and 
infrastructure  that  can  be  easily  maintained.  To  reduce  this  complexity,  the  infrastructure  was  thus 
changed to create static websites where all the pages using the content are created prior to deploying. 
This removed the need to release any database. 

4.2  Security 

As already stated, the initial MIDAS design involved the release of an online database. This was acceptable for 
MIDAS used as an internal Commission tool, but once it was released to the public, it brought with it all the 
security  risks  related  to  threats  to  such  databases  (such  as  ‘SQL  injection  attacks’).  The  maintaining  of  a 
secure online database is also an ongoing process and needs a constant review of policies and practices. The 
change  for  MIDAS  to  become  a  static  website,  as  described  in  the  previous  section,  removed  this 
security risk. 

12 

 
 
 
 
 
 
4.3  Performance 

The  release  of  MIDAS  to  the  public  made  it  even  more  essential  that  it  should  be  represented  by  an 
excellent, fast, informative, user-friendly website. Indeed, the initial infrastructure of using JavaScript 
executed by the browser and calling PHP scripts running on the server and communicating with the database 
to create dynamic webpages was quick enough for a Commission tool aimed at a few specialised users but 
not when opening to the public. 

Figure 2. Initial MIDAS public performance metrics 

The  performance  of  the  initial  MIDAS  public  website  was  evaluated  using  Lighthouse20  (an  open-source 
auditing  tool)  performance  metrics.  The  results  are  shown  in  Figure  2.  The  list  below  gives  a  very  brief 
summary of these measurements: 

  Performance: load time and quality of user experience (e.g. responsiveness to user input); 
  Accessibility: compliance with web accessibility best practices such as the presence of alt tags on 

images; 

  Best Practices: compliance with best practices for the web such as the use of HTTPS and other 

security criteria; 

  SEO: presence of Search Engine Optimization best practices that help search engines crawl the links 

and index the page. 

The performance score here clearly shows the limitation of the dynamic website solution. The communication 
time between the JavaScript and PHP scripts and the database had a negative effect on the user experience 
and performance. Figure 3 shows how the redevelopment of the website and the change to become a static 
website has improved all these scores, in particular performance. 

20 https://developers.google.com/web/tools/lighthouse/ 

13 

 
 
 
 
 
                                           
Figure 3. New MIDAS performance metrics 

Opening  MIDAS  to  the  public  also  increased  dramatically  the  probability  that  the  website  would  be  viewed 
using a mobile phone or tablet. The new MIDAS website has been optimized for mobile devices. 

4.4  Editor 

When  MIDAS  was  first  opened  to  the  Commission,  the  editor  was  open  to  all  registered  Commission’s 
modellers  and  policymakers  to  insert  and  maintain  the  metadata  elements.  This  was  a  very  useful  way  of 
gathering as much content as possible.  

Now, with the opening to the public, the editor has moved from being a front-end application available to end 
users to a back-end MIDAS administration tool, as indeed the MIDAS administrators ensure quality control and 
coherence of any new or updated information before entering it themselves using the editor.  

Communication  with  Commission’s  modellers  and  policymakers  regarding  updates  and  new  information  is 
thus an interactive process with the MIDAS team. This is necessary as person to person contact is very helpful 
to offer the appropriate  guidance and to ensure good  quality  and complete data is  provided the first time. 
This way of communicating also reduces the burden on the end users who are no longer required to learn how 
to use a software application in order to provide their information. 

14 

 
 
 
 
 
 
5  Functionality 

This  section  provides  a  brief  overview  of  the  functionality  and  content  provided  by  the  public  MIDAS 
website: factsheets (section 5.1), search (section 5.2) and explore (section 5.3) functions, the API (section 5.4) 
and publications (section 5.5). MIDAS public (Figure 4) uses the European Commission’s template library for 
its website styling.  

Figure 4. Home page (MIDAS public version) 

5.1  Fact Sheets 

Fact  sheets  are  online  data  sheets  that  contain  the  information  about  the  main  MIDAS  entities,  which  are 
models  and  impact  assessments.  Since  MIDAS  itself  is  the  main  source  for  information  on  models,  the 
metadata profile for models is much bigger and more complex than that one for impact assessments. Model 
metadata includes, for example, information on model licence and ownership, detailed structure, inputs and 
outputs,  model  quality  and  transparency,  useful  references  (Figure  5).  For  impact  assessments,  MIDAS 
provides information such as a description of the model contribution to the impact assessment, indicating the 
organisation running the model and supporting studies if applicable. For other details, MIDAS refers to other 
Commission’s information systems where the information is maintained. For example, for information on the 
published impact assessment document MIDAS refers to the Publications Office of the European Union. 

15 

 
 
 
 
Figure 5. Model fact sheet (MIDAS public version) 

The factsheets present relationships between entities e.g. which models were used in an impact assessment. 
Extensive use of tags highlights comparisons between entities. 

16 

 
 
 
 
5.2  Search 

Users can perform a standard search across all entities. Results can be filtered by model, impact assessment 
or model domain (Figure 6). 

Figure 6. Search (MIDAS public version) 

5.3  Explore 

Some predefined ways of easily exploring MIDAS information are offered. These include: 

  Departments (Figure 7): Impact assessments and models assigned to Commission’s policy 

departments (DGs). For each department, it is shown for how many impact assessments it was the 
lead department and how many models it made use of. The mentioning of departments also gives an 
idea of the policy area involved, e.g. department for Employment, Social Affairs and Inclusion (EMPL).   

  Model Domains: Models grouped by the main thematic areas they cover, e.g. agriculture. 
 

Impact Areas: Choosing a model for an impact assessment by the technical description alone is not 
easy. Knowledge about which models have been used in the past to assess particular impact areas 
can help. Here model contributions to impact assessments are grouped according to the impact areas 
that the model helped to assess. The impacts are structured into four impact areas: economic, social, 
environmental, and fundamental rights. They are further structured into categories and 
subcategories. The impact areas are based on the guidance provided by the Commission's Better 
Regulation framework21. 

21  One  of  the  key  roles  that  a  model  can  play  to  support  an  impact  assessment  is  contributing  to  the 
assessment  of  the  policy  options.  In  this  case  the  model  contribution  is  reported  in  MIDAS,  if  feasible, 
according to the Impact Areas, Impact Categories and Guiding Questions (Impact Subcategories) indicated 
in the better regulation Guidelines and associated ‘Toolbox’ (SWD (2017) 350). 

17 

 
 
 
 
                                           
Figure 7. Explore by departments (MIDAS public version) 

5.4  Application programming interface  

An  application  programming  interface  (API)  provides  users  with  lists  and  metadata  for  much  of  the 
information  contained  in  MIDAS.  This  is  important  for  a  Commission’s  service-oriented  architecture  as  it 
provides  a  computer-readable  way  for  other  departments  to  consume  the  MIDAS  data.  The  following 
information is included: 

  Models 
  Model Domains 
  Model Licences 
  Model Ownership 
  Model Tags 
  Model Types 
 
Policy Areas  
 
Impact Assessments  
 
Impact Areas 
  Departments  

Details regarding what is returned and code examples are provided in Figure 8. Results are returned as JSON 
files. 

18 

 
 
 
 
 
Figure 8. API (MIDAS public version) 

5.5  Publications 

This section includes information and access to a range of publications about MIDAS or referencing data from 
MIDAS (Figure 9). 

Figure 9. Publications (MIDAS public version) 

19 

 
 
 
 
 
 
 
6  Technical architecture 

This section describes the technical architecture of the MIDAS information system. 

Figure 20. MIDAS technical architecture 

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midas.jrc.cec.eu.int

web.jrc.ec.europa.eu

MIDAS Commission 
Website 

MIDAS Public 
Website 

webgate.ec.testa.eu

MIDAS Inter 
Institutional Website 

Gatsby

Gatsby

MIDAS DB

PHP/SQL

Editor

JRC I.05 LAMP

DIGIT LAMP

Modellers

Other Knowledge 
Management 
Systems

The  software  applications  developed  and  maintained  by  the  MIDAS  team  are  the  three  websites  and  the 
editor.  The  editor,  database  and  the  Commission  and  public  websites  are  all  deployed  on  an  environment 
provided  and  managed  by  the  JRC.  This  environment  includes  a  LAMP22  software  stack  and  a  method  of 
deployment  for  both  the  Commission  and  Public  websites  through  service  requests.  The  Inter-Institutional 
website  instead  is  deployed  in  a  similar  LAMP  setup  with  service  requests  but  this  time  provided  and 
managed  by  DIGIT.  Only  DIGIT  can  provide  the  possibility  to  deploy  a  website  to  the  webgate.ec.testa.eu 
environment accessible to the European Parliament and the Council. 

Each  of  the  websites  is  developed  using  the  Gatsby  static  site  generator  software  application.  Unlike 
database-driven  websites  (which  MIDAS  was  originally)  that  require  a  software  layer  to  deal  with  data 
requests  and  with  receiving  data  from  a  database,  Gatsby  generates  all  the  HTML  pages  of  the  website 
during  the  build  process  and  no  such  software  layer  is  required  and  no  database  is  released  with  the 
websites. Gatsby is JavaScript at its core and is built with React, GraphQL and Node.js. 

The editor application is built using the Laminas Project open source Model-View-Controller (MVC) framework 
and PHP component library. This application is database-driven and it uses PHP to connect and manipulate the 
MIDAS  MySQL  database.  The  editor  is  only  open  to  MIDAS  administrators  and  the  communication  with 
Commission’s  modellers  is,  by  necessity,  a  manual  process  that  allows  for  quality  control  and  clear 
communication  between  MIDAS  administrators  and  Commission’s  modellers.  Where  possible  the  editor 
connects to other existing knowledge management systems for its data.   

22 LAMP is an acronym referring to a general software stack: 

Linux operating system 

 
  Apache HTTP server 
  MySQL database management system 
 

PHP programming language 

20 

 
 
  
 
 
 
 
                                           
6.1  Service-oriented architecture 

The  MIDAS  software  applications  were  designed  to  sit  within  a  service-oriented  architecture  (SOA)  of  the 
European  Commission  that  encourages  reusability  and  interoperability  via  service  interfaces.  This  approach 
reduces redevelopment or duplication of existing functionality, ensures synergies and reduces maintenance. 
Within the SOA, MIDAS is the system documenting models and their contributions to impact assessments. As 
such  it  is  the  place  to  go  for  a  complete  metadata  profile  of  models.  This  metadata  is  made  available  to 
others through a standard application programming interface (API) that returns query results using JavaScript 
Object  Notation  (JSON).  The  API  offers  a  range  of  predefined  queries  so  information  can  easily  be  found 
easily. For example: 

 

 
 

The type of model e.g. Top-down Computable general equilibrium (CGE) model, Bottom-up Partial 
equilibrium (PE) model etc. 
Policy area the model has contributed to: e.g. transport, energy, environment etc. 
Impact area the model has contributed to e.g. competition, vehicle emissions, cost of doing business 
etc. 

For other entities within MIDAS (impact assessments, data and studies), MIDAS hosts only a minimal amount 
of information and instead queries services provided by other authorities. The other knowledge management 
systems services used by MIDAS are listed below. Note that the services relating to data are only relevant to 
the Commission and Inter-Institutional versions of MIDAS. 

 

Services provided by the Publications Office of the European Union  

o  EUR-Lex23: access to the Official Journal of the European Union (EU law). 
o  EU Publications24: access to publications (reports, studies etc.).  
o  EU Vocabularies25: access to vocabularies managed by EU institutions. 
o  EU Open Data Portal (ODP)26: datasets from EU institutions and other EU bodies like 

EUROSTAT.  

  Other services 

o  NASA:27 access to metadata for public NASA datasets. 
o  Food and Agricultural Organization (FAO)28: access to metadata for public FAO datasets. 
o  World Bank29: access to metadata for public World Bank datasets. 
o  Digital Object Identifier (DOI)30: access to publications metadata based on the unique 

publication number. 

o  Crossref31: access to citation information. 

23 https://eur-lex.europa.eu/homepage.html  
24 https://op.europa.eu/en/web/general-publications/  
25 https://op.europa.eu/en/web/eu-vocabularies  
26 https://ec.europa.eu/info/statistics/eu-open-data-portal_en  
27 https://data.nasa.gov/  
28 http://www.fao.org/faostat/en/  
29 https://data.worldbank.org/  
30 https://dx.doi.org/  
31 https://www.crossref.org/  

21 

 
 
 
 
 
 
 
                                           
7  Conclusions  

MIDAS  is  a  scientific  information  system  that  promotes  transparency  in  how  models  support  European 
Commission’s  impact  assessments  of  policy  proposals.  In  addition  to  facilitating  communication  and 
understanding  of  Commission’s  analyses,  this  also  strengthens  confidence  (of  decision  makers,  research 
bodies  and  the  public)  in  the  contribution  of  models  to  provide  evidence  in  support  to  policymaking.  By 
collecting  and  disseminating  information  on  model  quality  and  transparency,  MIDAS  also  contributes  to 
robustness and legitimacy of evidence that informs EU policies. 

The  use  of  models  has  become  increasingly  important  to  support  EU  policymaking.  This,  together  with 
enhanced  Commission’s  commitment  to  transparency  has  resulted  in  new  audiences.  With  these  new 
audiences  came  new  priorities  and  requirements  that  have  seen  MIDAS  evolve  from  being  a  model-centric 
comprehensive inventory to being much more focused on model contributions to impact assessments and the 
quality and understandability of the information being provided. In the future, we see the trends to prioritise 
quality over quantity and make the content easier to compare and analyse to continue. The use of codelists 
and  the  need  for  MIDAS  to  become  an  integral  part  of  the  service  oriented  architecture  of  the  European 
Commission will become ever more important. 

Over  time,  efforts  have  been  made  to  increase  the  quality  of  content  available  and  to  make  access  and 
analysis of the  high  variety of data available  as easy  and coherent as possible. The technology  behind the 
components of MIDAS have also changed and further architectural needs were addressed such as to improve 
performance, avoid technical debt, increase security and simplify the release process.  

By making the information easy for the public to navigate, MIDAS public also encourages scrutiny and further 
improvement of the quality of evidence provided, contributing to greater awareness by the public and better 
EU policymaking. Further developments of the MIDAS knowledge management system lie ahead. In the next 
few  months  (by early  2022), the MIDAS Inter-Institutional and  Commission websites  will  be brought in line 
with the public one. Once this alignment will be completed, further improvements to the content will also be 
addressed. These will concern for example a higher level of detail of the information provided in the quality 
and transparency sections, as well as introducing indications of the model input and output data sources. 

22 

 
 
 
 
 
 
References 

Acs, S., Ostlaender, N., Listorti, G., Hradec, J., Hardy, M., Smits, P. and Hordijk, L., Modelling for EU Policy 
support: Impact Assessments, EUR 29832 EN, Publications Office of the European Union, Luxembourg, 2019, 
ISBN 978-92-76-09671-9, doi:10.2760/748720, JRC117250 

Basyte  Ferrari,  E.,  Rosenbaum,  E.,  Listorti,  G.,  &  Ostlaender,  N.  (2020)  ‘Opening  and  Improving  Policy 
Development to Increase Public Trust: Transparency of Evidence-based Regulation in the Debate on EU Better 
Regulation Agenda’, The Crisis of Confidence in Legislation, 169–196, doi: 10.5771/9783748907244-169 

European Commission (EU Reference Scenario 2020) ‘Energy, Transport and GHG Emissions: Trends to 2050’,  
Publications Office, Luxembourg, 2021, doi: 10.2833/35750 

European  Commission  (2011)  ‘2011/833/EU:  Commission  Decision  of  12  December  2011  on  the  reuse  of 
Commission documents’, Official Journal of the European Union L 330, 14.12.2011, p. 39–42 

European Commission (2017) ‘Better Regulation Guidelines’, SWD(2017) 350 final, Brussels, 7 July. 

European Commission (2021) ‘Better regulation: Joining forces to make better laws’, COM(2021) 219 final, 
Brussels, 29 April. 

European Commission (2015) ‘Better Regulation for Better results - An EU agenda’, COM (2015) 215 final, 
Brussels, 19 May. 

European Commission (2019a) ‘Better Regulation: taking stock and sustaining our commitment’, COM (2019) 
178, Brussels, 15 April. 

European Commission (2019b) ‘Taking  Stock of  the Commission's  Better Regulation  Agenda.’,  SWD (2019) 
156, Brussels, 15 April. 

European  Parliament,  the  Council  of  the  European  Union  and  the  European  Commission  (2016) 
'Interinstitutional agreement of 13 April 2016 on Better Law-Making' Official Journal of the European Union 
L 123, 12.5.2016, p. 1–14 

European  Parliament,  the  Council  of  the  European  Union  (2001)  ‘Regulation  (EC)  No  1049/2001  of  the 
European Parliament and of  the Council of  30 May  2001 regarding  public access  to European Parliament, 
Council and Commission documents’, Official Journal L 145 , 31/05/2001 P. 0043 - 0048 

European  Parliamentary  Research  Service  (2019)  ‘Appraising  the  quality  of  the  European  Commission's 
impact  assessments.  Trends  and  developments  from  2015  to  2018’,  European  Parliamentary  Research 
Service, Ex-Ante Impact Assessment Unit, PE 642.807, December 2019 

Listorti, G., Basyte Ferrari, E., Acs, S., Munda, G., Rosenbaum, E., Paruolo, P. and Smits, P., The debate on the 
EU Better Regulation Agenda: a literature review, EUR 29691 EN, Publications Office of the European Union, 
Luxembourg, 2019, ISBN 978-92-76-00839-2, doi:10.2760/407003, JRC116035 

Listorti, G., Basyte-Ferrari, E., Acs, S., and Smits, P. (2020) Towards an Evidence-Based and Integrated Policy 
Cycle in the EU: A Review of the Debate on the Better Regulation Agenda. JCMS: Journal of Common Market 
Studies, 58: 1558– 1577. https://doi.org/10.1111/jcms.13053. 

Ostlaender, N., Acs, S., Listorti, G., Hardy, M., Ghirimoldi, G., Hradec, J. and Smits, P., Modelling Inventory and 
Knowledge Management System of the European Commission (MIDAS), EUR 29729 EN, Publications Office 
of the European Union, Luxembourg, 2019, ISBN 978-92-76-02852-9 (online), doi:10.2760/900056 (online), 
JRC116242. 

Ostlaender N, Bailly-Salins T, Hardy M, Perego A, Friis-Christensen A, Dalla Costa S. (2015) Describing models 
in  context  –  a  step  towards  enhanced  transparency  of  scientific  processes  underpinning  policy  making, 
(IJSDRI)  International  Journal  of  Spatial  Data  Infrastructures  Research,  Volume  10,  p.  27-54,  doi: 
10.2902/1725-0463.2015.10.art2, JRC95638 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
List of abbreviations and definitions 

BR   

Better Regulation 

CC-MOD   

Competence Centre on Modelling 

CoP 

DGs  

EPRS 

JRC 

Community of Practice 

Directorate-Generals (DGs) 

European Parliamentary Research Service 

Joint Research Centre 

MIDAS  

Modelling Inventory and Knowledge Management System of the European Commission 

 
 
  
 
  
 
 
  
List of figures 

Figure 1. MIDAS levels of accessibility ............................................................................. 10 

Figure 2. Initial MIDAS public performance metrics ............................................................... 13 

Figure 3. New MIDAS performance metrics ........................................................................ 14 

Figure 4. Home page (MIDAS public version) ....................................................................... 15 

Figure 5. Model fact sheet (MIDAS public version) ................................................................ 16 

Figure 6. Search (MIDAS public version) ............................................................................ 17 

Figure 7. Explore by departments (MIDAS public version) ........................................................ 18 

Figure 8. API (MIDAS public version) ................................................................................ 19 

Figure 9. Publications (MIDAS public version) ...................................................................... 19 

Figure 10. MIDAS technical architecture ........................................................................... 20 

 
 
Annexes 

Annex 1. MIDAS Public model description 

Acronym and title: The acronym under which the model is most commonly known 

Keywords: List of free keywords applicable for your model 

Model category:  

[  ]  Agriculture  

[  ]  Climate  

[  ]  Health   

[  ]  Economy  

Model home page: URL  

Overview 

[  ]  Energy  

[  ]  Environment  

[  ]  Fisheries  

[  ]  Population  

[  ]  Territory  

[  ]  Transport 

[  ]  Other  

Main purpose: Simple description for non-experts of the type and purpose of the model 

Summary: The who, what, why and how of the model 

Model type:  

[  ] Top-down Computable general equilibrium (CGE) model  

[  ] Top-down Dynamic Stochastic General Equilibrium model  

[  ] Top-down Input-output model  

[  ] Top-down Econometric model  

[  ] Top-down System dynamics model  

[  ] Bottom-up Partial equilibrium (PE) model  

[  ] Bottom-up Multi-agent model  

[  ] Bottom-up Micro-simulation model  

[  ] Bottom-up Simulation model  

[  ] Bottom-up Optimization model  

[  ] Process (or Physics)-based model  

[  ] Statistical model  

[  ] Cost-Benefit Analysis (CBA) model 

[  ] Other (specify and add definition): … 

Ownership (in the sense of Intellectual Property Rights (IPR)): 

 [   ] EU ownership (European Commission) 

 [   ] EU ownership (other than European Commission: e.g. European Parliament, European Central Bank, ...) 

 [   ] EU agencies’ ownership 

 [   ] Third-party ownership (commercial companies, Member States, other organisations, …) 

 [   ] Co-ownership (EU & third parties) 

 [   ] Other 

 
 
 
 
 [   ] Public domain 

Licence (informs about the general openness of the computer code): 

 [  ] free license        

[  ] non free license   

Details on model structure and approach: key assumptions, limitations and simplifications 

Model inputs: list of the key inputs used for the model 

Model outputs: list of the key outputs produced by the model 

Model spatial-temporal resolution and extent. 

Quality and Transparency 

Quality:  Details on model uncertainties, sensitivity analysis, external peer review and model validation. 

Transparancy:  Details on the availability of underlying data, model outputs, model documentation and model source code. 

Policy support 

Policy role:  If and how the model can be used in support of the policy cycle. Focuses on the potential of the 
model. 

Policy cycle:  The phase of the policy cycle the model is designed to contribute to 
[  ] Anticipation – such as foresight and horizon scanning  
[  ] Formulation – such as ex-ante Impact Assessments  
[  ] Implementation – this also includes monitoring    
[  ] Evaluation – such as ex-post evaluation   
[  ] Other: European Semester   

Policy area:  The policy areas the model is designed to contribute to   

 
 
 
 
 
[  ] Agriculture and rural development  

[  ] Banking and financial services  

[  ] Borders and security  

[  ] Budget  

[  ] Business and industry  

[  ] Climate action  

[  ] Competition  

[  ] Consumers  

[  ] Culture and media  

[  ] Customs  

[  ] Digital economy and society  

[  ] Economy, finance and the euro  

[  ] Education and training  

[  ] Employment and social affairs  

[  ] Energy  

[  ] Environment  

[  ] EU enlargement  

[  ] European neighbourhood policy  

[  ] Food safety  

[  ] Foreign affairs and security policy  

[  ] Fraud prevention  

[  ] Home affairs  

[  ] Humanitarian aid and  civil protection  

[  ] Institutional affairs  

[  ] International cooperation and development  

[  ] Justice and fundamental rights  

[  ] Maritime affairs and fisheries  

[  ] Migration and asylum  

[  ] Public health  

[  ] Regional policy  

[  ] Research and innovation  

[  ] Single market  

[  ] Sport  

[  ] Statistics  

[  ] Taxation  

[  ] Trade  

[  ] Transport  

28 

[  ] Youth  

Impact assessments: A list of the ex-ante impact assessments of the European Commission supported by 
the model.  Data is  provided  on who led the impact assessment, who ran the model and  details of how the 
model contributed. This contribution includes the role it played: 

[ ] baseline and assessment of policy options (most common case) 

[ ] contribution to baseline only 

[ ] problem definition 

[ ] (ex post) evaluation of existing policy 

It also includes where appropriate the impact areas (as described in the Better Regulation Toolbox) the model 
supported allowing policy analysts to find and check the suitability of the model more easily. 

If the contribution to the impact assessment is through a study that is also documented here. 

References 

References: Details for a list references about the model including: 

Studies that uses the model or its results 
Peer reviews 

 
 
  Model documentation 
  Other related documents 

29 

 
 
 
GETTING IN TOUCH WITH THE EU 

In person 

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nearest you at: https://europa.eu/european-union/contact_en 

On the phone or by email 

Europe Direct is a service that answers your questions about the European Union. You can contact this service: 

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- at the following standard number: +32 22999696, or 

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FINDING INFORMATION ABOUT THE EU 

Online 

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https://europa.eu/european-union/index_en 

EU publications 
You can download or order free and priced EU publications from EU Bookshop at: https://publications.europa.eu/en/publications. 
Multiple copies of free publications may be obtained by contacting Europe Direct or your local information centre (see 
https://europa.eu/european-union/contact_en). 

 
 
 
 
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doi:10.2760/909559

ISBN 978-92-76-44453-4