Last two on my assignment and I'm fully lost and no resource is helping
6. Find the least squares line fit of the form y = ax + b through the data
(-2,2), (1,0), (2,-4), (5,-6). What is the residual?
7. Find the least squares quadratic fit of the form y = ax^2 + bx + c through the data
(-3,1), (-2,2), (1,0), (2,-4), (4,-5), (5,-6). What is the residual?
#URGENT : Least squares line fit of the form
unborn mulch
high daggerBOT
Last two on my assignment and I'm fully lost and no resource is helping
6. Find...
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unborn mulch
URGENT : Least squares line fit of the form
Nothing I've done so far is working and Im runninginto issues and a lotta scratch out pages
winter scaffold
Last two on my assignment and I'm fully lost and no resource is helping
6. Find...
Plugging in all the data points gives a system of (linear) equations in the coefficients. You should know from class how to determine the least squares solution(s) to said system, which gives your fit.
The residuals are then just, if $f(x)$ is your fit, $y_i-f(x_i)$ for each data point $(x_i,y_i)$
frigid basaltBOT
Omegabet_
unborn mulch
Plugging in all the data points gives a system of (linear) equations in the coef...
I have to actively show all the matrices and I keep getting 3 dif answers
I think I got 6 thoguh
winter scaffold
You get Ax=b as your system, then the normal equations are obtained by left multiplication by the adjoint, which here is just the transpose
Like for 5 you get the normal equations as [34,6],[6,4]=(-42,-8)
Which has a unique solution since the matrix is invertible
@unborn mulch
unborn mulch
winter scaffold
probably
unborn mulch
should I open a new channel for new questions or keep it here?
winter scaffold
you can keep it here, but I'm unable to help further as of rn
unborn mulch
That’s ok! I’ll make a new one then!
winter scaffold
Plugging in the data gives the system $\begin{bmatrix}2&1\1&1\2&1\5&1\end{bmatrix}\begin{bmatrix}a\b\end{bmatrix}=\begin{bmatrix}2\0\4\-6\end{bmatrix}$
frigid basaltBOT
Omegabet_
winter scaffold
to which as said, you left multiply by the transpose of the coefficient matrix then solve the resulting system
unborn mulch
gotcha
unborn mulch
+close