I apologize in advance for how messy this is, I've never had to use latex.
\begin{matrix} 10 \\ 40 \\ 30 \\ 20 \end{matrix}
This is matrix A
\begin{matrix} 1 \\ 2\\ 3\\ 4\\ \end{matrix}
This is matrix B
\begin{matrix} 1 \\ 1\\ 1\\ 1\\ \end{matrix} This is matrix C
\begin{matrix} -9 \\ 17\\ -7\\ -1\\ \end{matrix}
This is matrix D
How does $A*4(B)*-15(C)=D$ ?
It's an example in my notes that I need to know, and for the life of me I can't figure it out. For more context:
$y_i=\alpha x_i+\beta+\epsilon_i$ for a regression chart, with matrix B being the x values and matrix A being the y values. Matrix D is the values of the $\epsilon$ values. How do we arrive at $\epsilon$?