Skip to main content

Section A.5 Regression

GeoGebra calculator ABC keyboard
Figure A.5.1. GeoGebra calculator ABC keyboard

Subsection A.5.1 Making a Scatterplot and Finding the Regression Line

We use GeoGebra's FitLine command to produce a regression line.

Make a scatterplot for the points \((10,12)\text{,}\) \((11,14)\text{,}\) \((12,14)\text{,}\) \((12,16)\text{,}\) \((14,20)\text{.}\) Then find the equation of the lease-squares regression line and plot it on top of the scatterplot.

We enter each of the five ordered pairs. The output history will show each labeled with a capital letter, such as \(A=(10,12)\text{.}\)

We do a Zoom to fit: right-click on the Graphics View (or click on the gear icon) and select Zoom to fit.

We next enter the FitLine command:

\begin{equation*} \text{fitline}(\{A,B,C,D,E\}) \end{equation*}

using the ABC keyboard shown above for the letters, the 123 keyboard (keyboard image) for the parentheses, and the f(x) keyboard (keyboard image) for the list curly braces {}.

Important: We must enter capital letters for the names of the points--GeoGebra is case-sensitive regarding labels.

Scatterplot and best fit line
You have attempted of activities on this page.