investigating and visualizing measurement error for novice “stem” learners scott a. sinex...
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Investigating And Visualizing Measurement Error
for Novice “STEM” Learners
Scott A. SinexDepartment of Physical Sciences and Engineering
Prince George’s Community CollegeLargo, MD
Presented at ASEE Conference 2014 in the Best Zone Paper Competition held in Indianapolis, IN on 15-18 June.
…want students to be able to• Know how good a measurement is• Graph and transform data • Derive mathematical models• Judge goodness-of-fit• Use simulations to explore multivariable models• Make predictions, interpret results, draw
conclusions • Develop conceptual understanding
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think like a novice and not an expert!
craft an experiment with careful scaffolding3
Calculate %errorList some possible causes
Change the mindset of studentsabout how to think about errors
Propagation of error
Students…
Faculty…
Developed four experiments…Stacking cookies
Nuts & Bolts of extrapolation
Stacking nested Styrofoam cups
Nuts & Bolts of let’s make an error
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ruler
balance
Each has data collection, model development, and simulations with error analysis
…and what do students do?
So let’s examine the stacking cookies experiment
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Just add data and presto you get a model
Enter data
Model (by linear regression)
Simulation to manipulate a variable
Predictions
6http://academic.pgcc.edu/~ssinex/excelets/NC/cookies_stack.xls
Best-fit line
How would you characterize the use of the “just add data” interactive Excel spreadsheet for this activity? Scale: very easy/easy/so, so /difficult/very difficult
Fall 2006 (n = 19 students) 3.5 out of 5 89% no difficulty
Fall 2007 (n = 10 students) 3.4 out of 5 100% no difficulty
Fall 2008 (n = 15 students) 3.6 out of 5 93% no difficulty
Fall 2010 (n = 15 students) 3.5 out of 5 80% no difficulty
Did you happen to notice that the rulers did not have the zero centimeter mark at the end? (all rulers had the zero mark off from the end) Yes No
Fall 2006 53% noticed error
Fall 2007 40% noticed error
Fall 2008 33% noticed error
Fall 2010 67% noticed error
If you did (circled yes in question 2), did you correct for it? Be honest! Yes No
Fall 2006 37% of total corrected error
Fall 2007 20% of total corrected error
Fall 2008 27% of total corrected error
Fall 2010 27% of total corrected error
For the Stacking Cookies Experiment
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…and what about ruler error?
8http://academic.pgcc.edu/~ssinex/excelets/Ruler_error.xls
Here we have induced a constant error
Nuts & Bolts of Extrapolation
Mass of boltby
extrapolation
Mtotal = Mnut* n + Mbolt
Determine massof the bolt on abalance - % error
Student data…and they whine over
the finding the equation
Verify model by just add data spreadsheet
n
Mtotal
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Enter data into Google form for discussion
Mass bolt with from one thru five nuts on it
The extrapolated value of the bolt
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The pedagogical approach…
…so now we can extent concepts using simulations11
Suppose we used magnesium nuts?
12http://epublications.bond.edu.au/ejsie/vol5/iss1/3/
Why change?
• NRC Framework Next Generation Science Standards
• Common Core Standards in Mathematics• AMATYC - The Right Stuff• MAA CRAFTY College Algebra• ASEE Innovation with Impact • Enhance 21st-century technology in classroom
(ISTE, Educause…)
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…and students
• Are actively engaged• Are using accessible technology• Are involved in science process• Must think • Must develop an understanding of the model• See many multivariable systems
• More interactive Excel spreadsheets, seehttp://academic.pgcc.edu/~ssinex/excelets/matsci_excelets.htm
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Questions and more info…• Scott Sinex
– See the paper in proceedings http://www.asee.org/documents/sections/middle-atlantic/spring-2013/Investigating-and-Visualizing-Measurement-Error-for-Novice-STEM-Learners.pdf
– Contact me - [email protected]
• My thanks to the ASEE Zone 1 selection committee!
• This work was supported by the NSF Division of Materials Research Partnership for Research and Education in Materials (PREM) Grant Numbers DMR-0611595 and DMR-1205608.
Thanks for coming today!!!
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