Linear Regression of Bone Mineral Density Scanners
A small specimen bone mineral density scanner.
Students complete an exercise showing logarithmic relationships and examine how to find the linear regression of data that does not seem linear upon initial examination. They relate number of BMD scanners to time.
Rarely in the real world does data collected by scientists and engineers fit an exact equation. Finding the equation of the line that fits the data best is a large part of what all engineers do when they collect and analyze data. In this activity, students practice this skill, especially as it involves using natural logarithms.
After this activity, students should be able to:
- Use the linear regression function on a graphing calculator.
- Explain how the natural logarithm can be used to linearize data.
CCSS.Math.Content.HSF-BF.B.5 (+) Understand the inverse relationship between exponents and logarithms and use this relationship to solve problems involving logarithms and exponents.
Grades 9-12
Do you agree with this alignment?CCSS.Math.Content.HSS-ID.B.6a Fit a function to the data; use functions fitted to data to solve problems in the context of the data.
Grades 9-12
Do you agree with this alignment?
STEL-3H Analyze how technology transfer occurs when a user applies an existing innovation developed for one function to a different purpose.
Grades 9-12
Do you agree with this alignment?
A2.S.ID.B.2.a Fit a function to the data; use functions fitted to data to solve problems in the context of the data.
Grades 9-12
Do you agree with this alignment?CCSS.Math.Content.HSF-BF.B.5 (+) Understand the inverse relationship between exponents and logarithms and use this relationship to solve problems involving logarithms and exponents.
Grades 9-12
Do you agree with this alignment?
Scientific Research
Grades 9-12
Do you agree with this alignment?
Each student needs:
- Linear Regression Activity Worksheet (PDF)
- Graphing Calculator Instructions (PDF), if needed
- graphing calculator
Students must be comfortable using graphing calculators (though detailed instructions are included). Students must also be familiar with linear graphing.
Now that we have learned the basics of natural logarithms, let's do a real-world activity that uses natural logarithms. What you are going to do with the provided data is something that many engineers do all the time. All types of engineers use natural logarithms to analyze data and you will be doing just the very basics of this type of data analysis.
Before the Activity
Make copies of the worksheet (and calculator instructions, if needed).
With the Students
Hand out the worksheets and explain the activity. This worksheet asks students to do a series of exercises with a graphing calculator. If students are familiar enough with graphing, they can do it on their own. If not, provide them with the detailed instructions on how to complete the graphing exercise. Note that one step in the instructions asks students to show their graphs to the teacher to check that they understand how to create a graph before moving to the next step.
Activity Embedded Assessment
Graphing Checkpoint: If students use the graphing calculator instructions, there is a checkpoint where the teacher can see if they understand how to correctly graph.
Post-Activity Assessment
Activity Worksheet: Collect and grade the activity worksheet for completion and accuracy. Review their data, graph, answers and work to gauge their mastery of the subject.
- For lower grades, provide the graphing calculator instructions.
- For upper grades, do not provide the graphing calculator instructions.
Contributors
Kristyn Shaffer; Megan Johnston
Supporting Program
VU Bioengineering RET Program, School of Engineering, Vanderbilt University
Acknowledgements
The contents of this digital library curriculum were developed under National Science Foundation RET grant nos. 0338092 and 0742871. However, these contents do not necessarily represent the policies of the NSF, and you should not assume endorsement by the federal government.
Copyright
2013 by Regents of the University of Colorado; original © 2006 Vanderbilt University