第七章

23题

第8章第二题 p213

代码实现

 clear,clc
 x = [0,4,10,15,21,29,36,51,68]'; n=length(x);
 y = [66.7,71.0,76.3,80.6,85.7,92.9,99.9,113.6,125.1]';
 X = [ones(size(x)),x];
 [b,bint,r,rint,stats] = regress(y,X);
 %y对t的回归方程为:y =67.5313+0.8719t



 %求y的预测区间
yt =67.5313+0.8719*25; %当t=25时，y的值
xt = [1,25]';
% L = xt' * xt;
%  L1 = inv(L);
L1=1/4060;
 u= sqrt(1+xt' * L1 * xt);
 t=tinv(0.975,7);
 sigmae=1.0152;
 yt1 = yt - sqrt(sigmae)*t*u
 yt2 = yt + sqrt(sigmae)*t*u

第五题 六题https://wenku.baidu.com/view/e0594fefbcd126fff6050ba6.html

第8题 方差分析

其他有关的练习https://max.book118.com/html/2018/0510/165800292.shtm 

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