Data Matters with Fathom! Dynamic Statistics™ software

Activity 9.1

The ability to find lines that describe, or fit to, points that line up on a scatter plot is built into statistical software. The software also can find lines that fit to points that do not line up, but for this project your task is to get comfortable with using the software to find lines that fit to points that can be on lines. In fact, you will be looking only at pairs of points and finding the lines that go through both points of each pair.

For the exercise, find the equations of lines and plot those lines for each school district in the following table from Data Matters. Your x-axis attribute is Lunch Rate, and your y-axis attribute is Reading Pass Rate.

Drag a case table onto the workspace. Add a Lunch attribute and a Pass attribute. Right-click on an attribute and add two cases. Enter the data for Auburn (using a decimal instead of “%”).

Select Analyze, Estimate Parameters, Empty Estimate, and finally, Linear Regression. Drag your x-axis variable onto Independent Attribute and your y-axis variable onto Dependent Attribute. The least-squares regression line that appears is the line that fits the points.

To get a graph of the relationship, drag a graph onto the table. Drag your x-axis attribute onto the x-axis of the graph and your y-axis attribute onto the y-axis.

Edit the case table to enter the data for each of the other districts.