用泊松逆高斯分布拟合已知数据

Question

现在给定一组数据，用R、MATLAB等使用泊松逆高斯分布拟合表二中的数据，需要得到过程代码，拟合后的参数r，β以及拟合效果图，谢谢！

Answer 1

clc;
clear;

t = 0:8;
data_real = [27141 5789 1443 457 155 56 27 2 2];

% sum = 0;
% for i = 1:8
% sum = sum + (i - 1)*data_real(i);
% end

mu = 5.5;
lambda = 9;

pd = makedist('InverseGaussian','mu',mu,'lambda',lambda);

%二项 负二项 泊松逆高斯分布

pos = pdf(pd,t);

pdf1 = pos*sum(data_real);

plot(t,data_real,'r');

hold on;

plot(t, pdf1, 'b');

title('项分布拟合图');
xlabel('索赔次数k');
ylabel('保单次数');

legend('真实值','拟合值');
dif = pdf1 - data_real;