CS 70 / 170 , Spring
نویسنده
چکیده
This linear system of equations will have a solution only when the vector ~y is contained in the column space of matrix X: that is, when ~y can be expressed as a linear combination of the columns of the matrix X. From a geometric perspective, this will occur when all points (xi, yi) lie precisely on a line. If, however, the points deviate even slightly from a perfect line, then ~y will not be in the column space of X, and there will be no solution to the above linear system. It is in these situations that we seek a solution that minimizes some measure of goodness of fit of a line to the points.
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