## Least-square method |
||

Let us have the set of values y (1) Σ(f(t We will find the solution in the class of the linear functions (straight lines): y = at + b. Then the term (1) we can write as the following Σ(a*t The necessary condition of the existence of minimum is the equality to zero of two partial derivatives on a and b accordingly: Σ((a*t Σ(a*t In designations Σt Σ(y Σ(t Σ(y Σb = bN the system can be rewritten as the following a*stt + b*st - syt = 0 a*st +b*N - sy = 0 Solving this system of two linear equations for a and b we will get a = (syt*N - sy*st)/(N*stt - st*st) b = (stt*sy - syt*st)/(N*stt - st*st) |

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calculated columns
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Computer firm
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data type conversion
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date_time functions
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edge
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exercise 7
exercise 70
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FOREIGN KEY
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FULL JOIN
GROUP BY
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IDENTITY
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