1. Structural-modelling explanations operate by recursively decomposing social mechanisms into sequences of cause and effect relationships. 2. Functions are important theoretical underpinnings in structural-modelling explanations, as causal variables are included because of their functions within the mechanism. 3. Functions can be understood as role-functions of the mechanism itself and its individual components within a functional architecture inferred from empirical research.

1. Functions and Mechanisms in
Structural-Modelling Explanations
Federica Russo
Philosophy, Kent
Joint work with
Michel Mouchart and Guillaume Wunsch

2. Overview
Structural-Modelling Explanations
The methodology
The recursive decomposition
Explanation and Mechanisms
Why mechanisms explain
Social mechanisms and recursive decompositions
Functions and Mechanisms
Role-functions and isolated descriptions
Functional architectures
Functions in S-M explanations

3. STRUCTURAL-MODELLING
EXPLANATIONS

4. Why do people drink?
Balts drink because it relieves stress
British drink to socialise
Mediterranean drink to accompany a lavish meal
…

5. Self-rated health in the Baltic countries, 1994-99

6. A step-wise methodology
Identify the
1. Formulate the causal hypothesis research question;
conceptual
variables;
2. Build the statistical model indicators; …
3. Test the model Conditional independence
properties; invariance;
exogeneity; …
4. Check congruence of results with background
knowledge
Do results make sense? Do they
feed further research? …

7. What are the causes of self-rated health
in the Baltic countries in the ‘90s?
Take the joint probability distribution + Make assumptions
P(Education, Locus of Control, Physical Health, …, Self-Rated Health)
P(X1, X1, X3, …Y)
perform a recursive decomposition of the type
P(Y)= P(X1) P(X3) P(X2|X3) … P(Y|X2, X3)
Read as:
Self-Rated Health depends on Education; on Locus of Control through
Psychological distress; on Alcohol Consumption which also depends on
Physical Health; …
7

9. Here, explanation is mechanistic explanation
Mechanistic explanation is successful insofar as
it spells out the functioning of the mechanism
Spelling out the functioning of the mechanism means
identifying the causes, their actions, and their effects
Yes indeed, we’re more epistemic than ontic.

10. Social mechanisms
may be decomposed
According to analytical sociologists, Little, Russo, ...
social mechanisms:
A plausible account of how change in social processes
is brought about through sequences
of cause and effect relations
That is … a recursive decomposition

11. Different mechanisms may explain
a same phenomenon
Different causes for a same effect
We can’t represent all mechanisms
by a recursive decomposition
Photosynthesis, for instance?
Not all models are explanatory
Better projections are based on associations

12. The function-ing of the mechanism
does the explanatory job.
Causal variables are included because of their
function in the mechanism.

13. FUNCTIONS AND MECHANISMS

14. Functions and functions
The function of the mechanism
Role-function (Cummins)
Isolated description (Craver)
The function of the components of the mechanism
Role-function

15. Functions in functional architectures
1. Observe properties of a social system
2. Infer the functional structure
3. Work out the causal mechanism (based on 2)
4. Confirm 2 based on 3

16. Functional
architecture
Empirical research
Causal mechanism

17. Functions in S-M explanations
Functions are role-functions
For the mechanism and for its components
Functions help build the conceptual model
They are the theoretical underpinnings of the causal variables
Causes are no less important than functions
Or, find the threshold between generality and specificity

18. To sum up
One way to S-M
The social S-M
do it: explanations
sciences aim explanations
structural- operate
to explain model
modelling functional
phenomena mechanisms
explanations individuation

19. Functions in S-M explanations
are the
theoretical underpinnings
of causes in a mechanism

20. Selected references
Craver C. (2001). Role functions, mechanisms and hierarchy. Philosophy of Science, 68(1).
Cummins R. (1975), Functional analysis. Journal of Philosophy, 72.
Demeulenaere P. (ed) (2011). Analytical sociology and social mechanisms. CUP.
Franck R. (ed.) (2002). The explanatory power of models, Kluwer.
C. and Wunsch G.(2010). Self-rated Health in the Baltic Countries, 1994-
1999, European Journal of Population, 26(4).
Little D. (2011), Causal mechanisms in the social realm. in P. Illari, F. Russo, and J. Williamson
(eds), Causality in the sciences. OUP.
McKay Illari P. and Williamson J. (2011). Function and organization: comparing the
mechanisms of protein synthesis and natural selection. Studies in History and Philosophy
of Biological and Biomedical Sciences.
Mouchart M. and Russo F. (2011), Causal explanation: recursive decompositions and
mechanisms, in P.Illari, F. Russo, and J. Williamson (eds), Causality in the sciences. OUP
Mouchart M., Russo F. and Wunsch G. (2010), Inferring Causal Relations by Modelling
Structures, Statistica.
Russo F. (2009), Causality and causal modelling in the social sciences: Measuring variations.
Springer.