灰色预测模型 matlab人口预测模型代码如下

%%发展系数a 灰色作用量b

syms a b;

%%原始数列 E列

A1 = xlsread(‘C:\Users\0223\Documents\MATLAB\劳动人口 .xlsx’,‘C1:C11’);

A = A1’;

A = A.*0.01;

n = length(A);

%%进行一次累加

B(1) = A(1);

for i = 2 : n

B(i) = B(i-1) + A(i);

end

%%均值生成

for i = 2 : n

Z(i) = (B(i) + B(i-1))*0.5;

end

Z(1) = [];

%%构造Y B矩阵

Y = A; Y(1) = []; Y = Y’;

B = [-Z;ones(1,n-1)];

%%计算a b参数值

q = sum(Z);

w = sum(A) - A(1);

e = 0;

for i = 2 : n

e = e + Z(i-1)*A(i);

end

r = 0;

for i = 2 : n

r = r + Z(i-1)*Z(i-1);

end

a = ( (qw) - (n-1)e ) / ( (n-1)r - (qq) );

b = ( (wr) - (qe) ) / ( (n-1)r - (qq) );

%%预测近4年的数据

yuce = [];

yuce(1) = A(1);

for i = 2 : (n + 4)

yuce(i) = ((A(1) - b/a))/exp(a*(i-1)) + b/a;

end

%%还原数据

huanyuan = [];

huanyuan(1) = A(1);

for i = 2 : (n+4)

huanyuan(i) = yuce(i) - yuce(i-1);

end

%%模型检验

canchazhi = abs(0.784 - 0.789691929) / 0.784