Single Regression Analysis
is used when there are one X and one Y.
And it uses the formulation,
It is useful. But it is the straight line. This page is made for curves.
For example, there is the data,
It looks like a curve.
In this case, we add the variable of square of X
Then we use the new variable as the "X",
We use X and Y to make 2-Dimension Scatter Plot . But we use square X and Y to do regression analysis.
We can use various formulation as X, for example, square X, sin(X), exp(X), log(X) and so on.
General quadratic curve is
We need the formulation of Multi-Regression Analysis . This is the point that starting data is one X and one Y but analysis data is more than two.
Multi-Regression Analysis is done using the variables, square X and X.