We define the vector variable
zt=(P1,t, P2,t, P3,t, MA1,t, MA2,t, MA1,t, Ftfund, Ftma)'.
In the following we denote the dynamical system by Φ, where zt=Φ(zt-1).
Additive dynamic noise can be introduced into the system to obtain zt=Φ(zt-1) + εt,
where εt=(εt, 0,0,0,0,0,0,0)' are iid random variables representing the model approximation error in that our model can only be an approximation of the real world. Because we assumed for all beliefs
| Vth(rt+1P)=Vth |
⎛ ⎜ ⎜ ⎝ |
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⎞ ⎟ ⎟ ⎠ |
=σ2 |
Vth(Pt+1)=Pt2 σ2 - Vth(Dt+1)=Pt2 σ2 - σδ2.
Therefore, when we add dynamic noise to the deterministic skeleton, we draw εt iid from a normal distribution with expectation 0 and variance σεt2=Pt2 σ2 - σδ2.
6.4 Trading volume
In this section we describe a procedure to determine trading volume. The total number of short or long positions transferred from belief b to belief h at time t converges in probability to zt-1b qth as the number of agents, each having zero market power, converges to infinity. The total number of long and short positions transferred to belief h from the other beliefs converges then in probability to
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(40) |
| zth= |
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