Workshop on Teaching Introductory Statistics Session 5: Finding and Using Real Data

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Workshop on Teaching Introductory
StatisticsSession 5 Finding and Using Real
Data

• Roger Woodard, North Carolina State
  UniversityGinger Holmes Rowell, Middle Tennessee
  State University
• Medical College of Wisconsin in Milwaukee
• July 11, 2006

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Overview

• GAISE recommendations
• Some specific sources for real data
• Using data collection devises an example
  other sources of examples
• Finding data for your topics

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Pre-GAISE Heeding the Call for Change (Cobb,
1992)

• Students need to recognize that
• Personal decisions should be based on evidence
  (data) acting on assumptions not supported by
  data can be dangerous
• Formulating problems getting good data is
  difficult and time-consuming (experience makes a
  believer)

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GAISE says Use Real Data

• Reasons for Use
• Authenticity
• Considering collection or production issues
• Relating analysis to problem context
• Engaging students in thinking about relevant
  statistical concepts

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GAISE Understanding the Process

• Students should understand the parts of the
  process through which statistics works to
  obtain or generate data
• An important aspect of dealing with real data is
  helping students learn to formulate good
  questions and use data to answer them
  appropriately based on how the data were
  produced. GAISE, Recommendation 2, paragraph 1

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Understanding the Process Various Examples

• Have students formulate their hypotheses first (a
  separate hand-in homework)
• Student generated surveys
• Question wordings see how difficult (critique
  another groups survey questions)
• Question ordering (run an in class experiment)
• Measurement Errors
• Students all take measurements and graphs the
  errors for the class

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GAISE Types of Data Examples

• Archival data
• surveys, websites, articles, Readers Digest
• Class generated data
• surveys quick polls, measurements, data about
  the students, experiments, data collection
  devises
• Simulated data
• flip coins, roll dice, computer simulations

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Types of Data, continued

• GAISE Appendix descriptions
• Naked data (without context)
• Realistic data (could be a realistic scenario,
  but the data has been made up)
• Real data (the real thing)

http//www.amstat.org/education/gaise/GAISECollege
AppendixD.htm
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Some Teaching Tips from GAISE

• Make it interesting to STUDENTS(!)
• Use a variety of contexts
• Keep class generated contexts safe
• Use data to answer questions relevant to the
  context
• Show how data collected can generate new
  questions

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Teaching Tips, continued

• Use a rich data set for multiple topics
• Example Cicada Data
• Real, timely, student collected, for biology
  students taking statistics
• Used for multiple topics
• Descriptive statistics, graphical
  representations, writing reports
• 2-sample t-tests (gender)
• ANOVA (3 species)

DATA URL http//www.math.uah.edu/stat/data/Cicad
a.xhtml
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Specific Sources for Real Data

• Using the Internet
• See handout
• Examples - Archival
• Titanic dataset (compliments of Lisa Green)
• NBA dataset (compliments of Roger Woodard)

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Specific Sources for Real Data

• Examples Student Generated Data
• Simple Examples
• Beginning of the semester survey (short)
• Estimate number of red books in the library
• Examine variability around us go outside and
  take some measurements (pine cones, leafs, )
• Data Collection
• Forensic cases (handouts)
• Grip strength (demo)

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Grip Strength Activity

• Idea Example of matched pairs
• Two measurements on one subject.
• One sample t-test.
• Goal Get students involved in the whole
  process Collection through analysis.
• Carpenter example.

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Grip Strength Activity

• Makes use of TI-83/84 data collection probes.
• Many probes available including
• Heart rate, temperature, soil moisture,
  respiration, EKG, BP, light sensor,
  Accelerometers
• Link to Calculators through CBL or through easy
  link.
• Allow easy collection of data.
• www.vernier.com

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Grip Strength Activity

• Hand Dynamometer
• Measures grip strength in Newtons
• Measure 10 volunteers
• Both right and left hand
• Record both values and take the difference

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Grip Strength Activity

• Students must make decisions about the data
  collection process.
• Issue of measurement error.
• When do we measure?
• Sources of variability.
• What position are students in when taking
  measures.
• Design issues.
• Do we randomize?

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Grip Strength Activity

• Generate hypotheses
• Before data collected
• Think about hypotheses related to real situation.
• Collect data
• Can use calculators to save time
• Make conclusion
• About H0 and about real situation

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Specific Sources for Real Data

• Examples Simulated data
• We will generate simulated data in the technology
  sessions.

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Its Your Turn

• Working in your groups, identify some datasets
  that

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References

• Cobb, George. (1992). Teaching statistics. In
  Lynn A. Steen (Ed.), Heeding the call for change
  Suggestions for curricular action (MAA Notes No.
  22), 3-43.
• GAISE College Report Appendix, found at
  http//www.amstat.org/education/gaise/, viewed
  7/3/2006