demonstrate sample variance unbiased
% %%无偏估计验证 % %%总共容量 M=7; % %%样本容量 N=2; % %填充第一列 % %填充循环次数 for t=1:M^(N-1) for i=1:M Sample1((i-1)M^(N-1)+t) = i; end end % Sample1' % %填充第二列 for t=1:M for i=1:M Sample2(M(t-1)+i) = i; end end % Sample2' Sample = [Sample1',Sample2'] sLenght = length(Sample); for s=1:sLenght subSample = Sample(s,:) stdSample(s) = var(subSample,1); end stdSample = var(Sample'); stdSampleE = sum(stdSample)/M^N Total = 1:M; stdTotalE = var(Total,1)
Sample =
1 1
1 2
1 3
1 4
1 5
1 6
1 7
2 1
2 2
2 3
2 4
2 5
2 6
2 7
3 1
3 2
3 3
3 4
3 5
3 6
3 7
4 1
4 2
4 3
4 4
4 5
4 6
4 7
5 1
5 2
5 3
5 4
5 5
5 6
5 7
6 1
6 2
6 3
6 4
6 5
6 6
6 7
7 1
7 2
7 3
7 4
7 5
7 6
7 7
subSample =
1 1
subSample =
1 2
subSample =
1 3
subSample =
1 4
subSample =
1 5
subSample =
1 6
subSample =
1 7
subSample =
2 1
subSample =
2 2
subSample =
2 3
subSample =
2 4
subSample =
2 5
subSample =
2 6
subSample =
2 7
subSample =
3 1
subSample =
3 2
subSample =
3 3
subSample =
3 4
subSample =
3 5
subSample =
3 6
subSample =
3 7
subSample =
4 1
subSample =
4 2
subSample =
4 3
subSample =
4 4
subSample =
4 5
subSample =
4 6
subSample =
4 7
subSample =
5 1
subSample =
5 2
subSample =
5 3
subSample =
5 4
subSample =
5 5
subSample =
5 6
subSample =
5 7
subSample =
6 1
subSample =
6 2
subSample =
6 3
subSample =
6 4
subSample =
6 5
subSample =
6 6
subSample =
6 7
subSample =
7 1
subSample =
7 2
subSample =
7 3
subSample =
7 4
subSample =
7 5
subSample =
7 6
subSample =
7 7
stdSampleE =
4
stdTotalE =
4
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