设 [tex=2.0x1.214]vnzjVhyzo/NIhVUgFyjLlA==[/tex] 都是 [tex=0.643x0.786]/he/ol8BkDuTTL9yMPtH4Q==[/tex] 阶半正定实对称矩阵, 求证: 存在可逆实矩阵 [tex=0.714x1.0]YiLkHgl7MlxE+QjUplQUKA==[/tex], 使[tex=30.286x1.429]NG5DOe/S5ZBvb+Wli+5nT1ZbBy0YinX4DrDR9SJWzd7pQZQLxZI8LR0hJLJSfvNDv3twoCDSaWhLZJDWe9Ni/NxK/A5WbCe7E2inrT2f29lLGjkw0qxnhozjA+i8EvpEU/bEnLVaU24RHeGWmjq5+/UDCtFCNlv6hMfcQ41xxi/rQdJPKPfOP6udBVeueUb40TP+klDXu/q7fjbZDasAECf1niWMIw/8ZHwvT7sZNaWgUpoewoLQo9DMBQTR2iNW/q6Ue2jwqZVKXJTXtEH78w==[/tex]

 设某联立方程模型的第 1个随机方程为[tex=8.929x1.214]omW94IETGTL9jPlpmuLfbEgxJOrQXEk5srs0YgaSFLHD3OxIoULWKeXS2x5ezGMiLopoZlP2l5GP5ITXhXycnkY1wXybwohVRDv4kWBZOZ0OeXkB4bU2XzTKDG5IGnNtTGLkVngSGhiSdBmxFbCWkJHTYZlx6UwsZVOeTjo6mdI=[/tex]其中，[tex=1.071x1.214]hYGxNzBBBuBP6FtZSjdF28xb0excp6TIY6+KvyjcFlY=[/tex]为该方程所含的内生解释变量行向量，[tex=1.357x1.214]ZL4OSwbgka8hhT6CpJpo0QLsJa5fR+aHSyRpXVRvOIk=[/tex]为该方程所含的先决变量行向量。[tex=3.143x1.214]U9s0BBfTC9alh/yBPBgczl8H0NcbkCCwvYxGOSx3SfvkeAzolpU3EA89t1CBYI+OTG1gG1c1vQY3eWW58WUBEg==[/tex]为对应的参数列向量。在-一个样本容量为n的样本下，可写出如下矩阵的形式[tex=13.286x2.786]hYGxNzBBBuBP6FtZSjdF22MIJkfZvGW1LX5DZghGOUD2SukAiSXVQmJdnK7ycdwNOJNsFpz22V2pQgpxUTljUj51zhdf3Yp9UNK7/2K8Z/aNR/M+cikfoCQPCQo4Kzff3lA3mCjdiFfTWTbI/gS+kxz8xDnFgcYRZz1UoGQ756QpIii1vwtOtQKeDYdOPndIXyDgn543zUZjYheDYon6QB922YyHagw/TUccbzjBS+Pm6mGKmeuM4fx227VeoZcz8yakhU4LjwDgYFKjTSWJvRXVv55lwYeUAiBPHRhoipbx0hl7XmzdTY65dkGaXhWD3QZwZz/y7MbXfXtXcd3Qxg==[/tex]试推导出如下间接最小二乘估计法的表达式[tex=16.071x3.571]yZSoi3OqRDHA0jMpBBfkra2QPZ6L6fYaDdLngdqh5xTkk4D1iEpzmCWV84EoJr/gtWdn7JwpwuqMUYmXL5uz9rI6eR9dZO5B/uxCkJjqBk5XX4xqfS0ry/C6IlLUOrdfheCVOIXCi7kGn2wy8Z24ZMtpRqcdkdAXzmb0h8c7zi+TocVSEzBM6c0DbuRH3M6VmR0UA48gzD/BW1UOKjeHooqz+cg1Og+qUWaZABpT6AmNFyuTvnJdONpAl3PfLZUMNk28IWo8qkmJRkPE8M1ufIQLQjv7eE5tTHFwQpRpmWOuS91ZJpYAwrXU0c0S2Zcg4YAXzSJi6NCn/h+fEzOfjmG64HimJS0prOi6PA7rWNrHOu4b39ZnOybnjU6aj8f4UV6YGg99ml0Go03e0WnzFA==[/tex]其中，X为联立方程模型全部先决变量在容量为n的样本下组成的nxk阶矩阵。