%We now consider 10 distinct echo chambers, each starting with its own
%slant.  Five are slanted negative, five are slanted positive.

%delete extraneous data from previous programs that have been run
clear
clc

%Generating the initial opinions

%population size
Chambers = 10;
PopSize = 100;

%The list of everyone's opinions
Opinions = zeros(1,PopSize*Chambers);
Allegiances = zeros(1, PopSize*Chambers);

for run = 1:12
%Initializing the opinion vector and the allegiance vector
for j = 1:Chambers/2
    for i = 1:PopSize
        if i <= PopSize*0.3
            Opinions((j-1)*PopSize + i) = 1;
            Allegiances((j-1)*PopSize + i) = 10;
        else
            if i <= PopSize * 0.55
                Opinions((j-1)*PopSize + i) = 2;
                Allegiances((j-1)*PopSize + i) = 30;
            else
                if i <= PopSize * 0.75
                    Opinions((j-1)*PopSize + i) = 3;
                    Allegiances((j-1)*PopSize + i) = 50;
                else
                    if i <= PopSize*0.90
                        Opinions((j-1)*PopSize + i) = 4;
                        Allegiances((j-1)*PopSize + i) = 70;
                    else
                        Opinions((j-1)*PopSize + i) = 5;
                        Allegiances((j-1)*PopSize + i) = 90;
                    end
                end
            end
        end
    end
end
for j = Chambers/2 + 1 : Chambers
    for i = 1:PopSize
        if i <= PopSize*0.1
            Opinions((j-1)*PopSize + i) = 1;
            Allegiances((j-1)*PopSize + i) = 10;
        else
            if i <= PopSize * 0.25
                Opinions((j-1)*PopSize + i) = 2;
                Allegiances((j-1)*PopSize + i) = 30;
            else
                if i <= PopSize * 0.45
                    Opinions((j-1)*PopSize + i) = 3;
                    Allegiances((j-1)*PopSize + i) = 50;
                else
                    if i <= PopSize*0.70
                        Opinions((j-1)*PopSize + i) = 4;
                        Allegiances((j-1)*PopSize + i) = 70;
                    else
                        Opinions((j-1)*PopSize + i) = 5;
                        Allegiances((j-1)*PopSize + i) = 90;
                    end
                end
            end
        end
    end
end

% Now, in each conversation, 90 percent of the time the speaker and
% listener are forced to be from the same chamber.  The remaining 10
% percent of the time, the speaker and listener are randomly chosen from
% the general population, possibly from the same chamber, possibly not.


for conversations = 1:1000000
    %the probability of an in-chamber conversation
    B = rand;
    if B < 0.9
        j = randi(Chambers);
        S = randi(PopSize);
        L = randi(PopSize);
        Speaker = (j - 1)*PopSize + S;
        Listener = (j - 1)*PopSize + L;
    else
        Speaker = randi(Chambers * PopSize);
        Listener = randi(Chambers * PopSize);
    end
    Question = randi(4) + 0.5;
    if Opinions(Speaker) > Question
        if Opinions(Listener) == Question - 0.5
            A = rand;
            BaseOdds = 1/9;
            AllegianceOdds = Allegiances(Listener)/(100 - Allegiances(Listener));
            TotalOdds = BaseOdds * AllegianceOdds;
            Threshold = TotalOdds/(1 + TotalOdds);
            if A < Threshold
                Opinions(Listener) = Opinions(Listener) + 1;
            end
        end
        Allegiances(Listener) = min(99, 100 - 0.9*(100 - Allegiances(Listener)));
    else
        if Opinions(Listener) == Question + 0.5
            A = rand;
            BaseOdds = 1/9;
            AllegianceOdds = (100 - Allegiances(Listener))/Allegiances(Listener);
            TotalOdds = BaseOdds * AllegianceOdds;
            Threshold = TotalOdds/(1 + TotalOdds);
            if A < Threshold
                Opinions(Listener) = Opinions(Listener) - 1;
            end
        end
        Allegiances(Listener) = max(1,0.9*Allegiances(Listener));
    end
end

    figure(1)
    subplot(3,4,run)
    histogram(Opinions, linspace(0.5,5.5,6))
    xlabel opinion
    ylabel popularity
    figure(2)
    subplot(3,4,run)
    histogram(Allegiances, linspace(0, 100, 21))
    xlabel allegiance
    ylabel popularity
    
    for chamno = 1:10
        a = floor((chamno-1)/5);
        b = mod((chamno-1), 5);
        figure(2*run + 1)
        subplot(5,2,2*b + a + 1)
        edges = [0.5, 1.5, 2.5, 3.5, 4.5, 5.5];
        histogram(Opinions((chamno - 1)*PopSize + 1:chamno*PopSize), edges)
        xlabel opinion
        ylabel popularity
        figure(2*run + 2)
        subplot(5,2,2*b + a + 1)
        edges = linspace(0, 100, 21);
        histogram(Allegiances((chamno - 1)*PopSize + 1:chamno*PopSize), edges)
        xlabel allegiance
        ylabel popularity
    end
    run
end