SLIDE 1 Annihilation of Information Destabilizes Speculative Markets
Klaus Pawelzik with Felix Patzelt Institute for Theoretical Physics University Bremen
SLIDE 2
Markets are dynamical systems
SLIDE 3
Markets are in some equilibrium !? Markets are close to a critical state ?!
SLIDE 4
A new mechanism: self-organized critical control
SLIDE 5 t T t t t
M T T T
) (
1
Continuous closed loop control in humans
Mouse Balancing Dynamics:
SLIDE 6 Power laws of human control
Y Y P ) (
- F. Patzelt & K. P., Phys. Rev. Lett. 2011.
Line: Adaptive control with reaction delay
The Principle of Information Annihilation
- F. Patzelt & K. P., Frontiers Comp. Neurosci. 2008.
SLIDE 7
... also in financial markets?
SLIDE 8 A Minimal Realistic Market Model as Adaptive Control System
- Markets are systems of interacting agents
- Agents' actions are orders (puts and calls)
- Prices are generated deterministically
Dynamics? Adaptation? Control?
SLIDE 9 Ingredients 1
The Price:
t t t
p
demand ) ( ) (
t t t t t
p p p
demand
t t t
p
demand
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Ingredients 2
The (Log-)Return:
1
ln
t t t
p p r
SLIDE 11 Ingredients 3
N i t i i N i t i i t
S M p
1 ) ( 1 ) (
) 1 (
P S M i N
i i
,..., 1 ns' informatio '
depend 1,0 decisions s Agent' stocks and money with agents random
i
SLIDE 12 Ingredients 4
Trading at price p (conservation of assets):
i i i i i i i i i i i i
p S M S S p M S M M 1 ) 1 ( 1 ) 1 ( 1
- free risk parameter
SLIDE 13 Ingredients 5
- Intrinsic information = signs of past m returns
'Endogenous Information'
m
P P t r t t 2 ) ) ( ( ) ( 2 ( ) 1 ( , mod
- Extrinsic information = random
'Exogenous Information'
P
t
,..., 1
SLIDE 14 Exogenous Information becomes annihilated! Trading is an efficient learning algorithm!
1 . , 5 , 27 m N
Results 1:
Dynamics from extrinsic information
SLIDE 15 Results 2:
A critical point for exogenous information
Trading is an optimal learning algorithm!
N
m
2
2 / 1
c
SLIDE 16 Results 3:
Dynamics from intrinsic information
5 . , 12 , 212 m N
SLIDE 17 What causes the large price jumps? (part one)
01 . , 12 , 2 , 2
6 12
m N N
P
, endogenous information
SLIDE 18 Results 4:
High kurtosis fluctuations beyond critical line! Phase diagrams: reduction of return magnitude: kurtosis of return distribution:
SLIDE 19 Results 5: Homogenous exogenous information
Phase diagrams: reduction of return magnitude: kurtosis of return distribution:
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What causes the large price jumps? (part two) Correlations of returns with surprise:
SLIDE 21
Results 6:
Self-referential dynamics can reproduce stylized facts!
SLIDE 22 Efficient adaptive control in financial markets can explain extreme return fluctuations
- Redistribution of assets via trading is equivalent to an efficient learning
rule with the objective of minimizing predictable price fluctuations.
- 'Rationality' of a market as a whole can rely on simple agents (idiots)
as long as they are sufficiently diverse. Non-negativity:
- Removement of predictable fluctuations from endogenous information
(e.g. when speculation is dominant) destabilizes the dynamics and results in large return fluctuations. 2 / 1
c
The 'Information Annihilation Instability' (IAI) is a general principle that dominates many systems involving rapid adptive control.
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See our poster #49
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Thank you!
Thanks to Josephine Mielke
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see also our paper at http://arxiv.org/abs/1211.6695