mk_test.m

m-k检验

%by Sun Min
%Email:[e-mail]
clear;
fid=fopen('T-jones.txt','r');
a=fscanf(fid,'%f',inf);
a=a';
fclose(fid);
n=length(a);
b(1:n)=a(n:-1:1);
ra=zeros(1,n);
rb=zeros(1,n);
UF=zeros(1,n);
UB=zeros(1,n);
for i=2:n
    ra(i)=ra(i-1)+length(find(a(1:i)<a(i)));
    rb(i)=rb(i-1)+length(find(b(1:i)<b(i)));
    E=i*(i-1)/4.0;
    Var=i*((i-1)*(2*i+5))/72.0;
    UF(i)=(ra(i)-E)/sqrt(Var);
    UB(i)=(rb(i)-E)/sqrt(Var);
end
UB(1:n)=-UB(n:-1:1);
x=[1001:1980];
plot(x,UF,'r');
axis([1001 1980 -15 15]);
hold on;
plot(x,UB,'b');
plot(x,1.96*ones(1,n),'--');
plot(x,-1.96*ones(1,n),'--');
legend('UF','UB');
text(1700,3,'U_{0.05}=+1.96');
text(1700,-3,'U_{0.05}=-1.96');
title('北半球平均温度距平M-K检验','FontSize',14);
xlabel('年份');
saveas(gcf,'M-K','jpg');