Need advice on my code for probability simulation

I am attempting to simulate this model below and output a transition matrix at the end.

I am having trouble with the last part of the code (see comment % help and % end help) where I am trying to list all possible outcomes and their probabilites (BB is the probability of buy buy, etc.) and output a transition matrix.

I have attempted this manually which is ok for a simulation of this size but if I wanted a larger simulation is there any way I can code this section instead of typing it all out manually?

A = [0 1
       0 0]; % sets A equal to adjacency matrix of network of agents

j = [1
     1] % sets j equal to pre-set states of agents in network

AgentStates = repmat( { 'Buy' }, numel( j ), 1 ); 
AgentStates( j == -1 ) = { 'Sell' } % lists agent states

A1 = j(1,1);
A2 = j(2,1);

K = 0.85; % sets value of constant 'k'
J = 0.8; % sets value of constant 'j'

S = sum(j) % sets the sum of states in network

p = (-K*S)/J % sets p equal to the value E must be greater than or less than in probablity distribution

PD = makedist('Normal','mu',0,'sigma',1); % normal distribution with mean '0' and variance '1'
PB = 1-cdf(PD,p) % finds the probability of a buy state using normal distribution
PS = cdf(PD,p) % finds probability of sell state using normal distribution

    BB = PB*PB; % NEED HELP
    BS = PB*PS;
    SB = PS*PB;
    SS = PS*PS;

    T = [BB*BB BB*BS BB*SB BB*SS
         BS*BB BS*BS BS*SB BS*SS
         SB*BB SB*BS SB*SB SB*SS
         SS*BB SS*BS SS*SB SS*SS] % END HELP

G = digraph(A);
P = plot(G); % plots graph 'G' 
title('Network of Agents'); % sets title of graph

[James Tursa]

"... if I wanted a larger simulation ..."

In what way would it be larger? I.e., which additional variables would you have and how would T be built differently?

Answer 1

[Devraj Dutt]

Have you tried transprob (https://www.mathworks.com/help/finance/estimation-of-transition-probabilities.html).