The staged modeling approach combines relevance and rigor in interdisciplinary research. It uses an intermediate complex model called the Data Integration Model (DIM) that includes all relevant social science factors. Simpler models are then developed based on the DIM and validated against it. This allows social and natural scientists to collaborate effectively using models tailored to their strengths. Comparing reduced models to the DIM showed distinctive high and low voter turnout regimes. Network dynamism increased turnout while household immigration reduced it compared to individual immigration. The staged approach enabled hypothesis testing and policy insights while achieving both relevance and mathematical rigor.

1. Staged Models for Interdisciplinary
Research
Combining Relevance and Rigour
The SCID Project Members
(but particularly in this part of the work:
Luis Fernandez Lafuerza, Louise Dyson,
Bruce Edmonds and Alan McKane)

2. Rigour and Relevance
With complex systems one is faced with using:
– A simple model that can be completely analysed
– A complicated model including the known processes
• Choosing between rigour or relevance
Often when formal (e.g. physicists) and social scientists
collaborate there is some dissatisfaction:
– Formal scientists dislike models they don’t understand
– Social scientists dislike models with abstract micro-level
SCID has tested out an approach which uses a
(complicated) descriptive model which reflects evidence
which is then, itself, modelled with simpler models that
can be adequately analysed
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 2

3. Our Basic Approach…
…is to stage abstraction with an intermediate, complex
model, that is then, itself, modelled (a ‘KIDS’ approach)
• The Data Integration Model (DIM) includes all that is
deemed relevant by social scientists
• The simpler models of the DIM are developed by
formal scientists but validated against the DIM
Data Evidence
Simple Model
Data Evidence
Simple Model
Complex Model
Representation
Simplification
DIM
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 3

4. Reduced Simulation ModelsReduced Simulation Models
Overall Strategy
Data-Integration Simulation Model
Micro-Evidence Macro-Data
Reduced Simulation Models
Analytic Model
Even Simpler Simulation Model
Reported in
this
presentation
Currently
being
developed
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 4

5. Outline of Model Reduction
Red and green processes were somewhat
simplified, also parties and (initially) social network
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 5

6. Comparison of Reduced and DIM
Models
Low and high turnout regimes
Broad agreement between models, but different
levels and different dynamics in transition region
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 6

7. With Different Kinds of Network
Blue = Clumped Network, Green = With “clumped”
network, Red = no network (bistability in transition)
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 7

8. Synthetic Network
Kinds of network
A synthetic network that is composed of small
groups with some random inter-group connections
resulted in better fit of dynamics
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 8
Network in DIM

9. Fixed vs. Dynamic Networks
Reduced models with fixed ‘clumped’ network (blue)
and with a dynamic network where links between
households change (red)
Dynamism increases turnout due to diversity of links
over time allowing wider influence
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 9

10. Individual vs. Household
Immigration
With immigrants of either a lower or higher political
interest than natives, individual immigration resulted
in higher level of turnout than household
immigration, due to asymmetry of influence process
Low Interest Immigrants High Interest Immigrants
Individual
Immigration
Family
Immigration
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 10

11. Final Comparison
Reduced model + dynamic ‘clumped’ network +
household immigration had good fit to DIM turnout
dynamics but amenable to complete checking,
much simpler and easier to experiment with
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 11

12. What was Learnt?
The comparisons suggested that:
• distinctive ‘high’ and ‘low’ turnout regimes exist,
depending on rate of discussions
• when in extreme turnout regimes, the system is
stable, whereas in the transition regime turnout
can 'flip' between low and high
• the lack of bistability in the transition is due to the
‘locality’ and sparseness of the network
• the dynamism of the network resulted in higher
turnout levels
• household immigration reduced turnout compared
to individual immigration
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 12

13. Conclusions
• Relevance and rigour combined via a ‘chain’ of
highly related models (not in a single model)
• Intermediate abstraction step of a DIM
• Enabled social and formal scientists to work
effectively together, each to their own strengths –
crucial communication via a (complicated) model
• Each model acts as a check on the other
• Policy relevant hypotheses found
• Further iterations of model simplification in
progress towards completely analytic models
Staged Models for Interdisciplinary Research, SCID Final Meeting, Crewe, July 2015, slide 13

14. Thanks!
The SCID project:
http://scid-project.org
The Full Voter Model:
http://openabm.org/model/
4368
Slides at:
http://www.slideshare.net/
BruceEdmonds