MATH 6350

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MATH 6350

• Ginger Holmes Rowell, Ph. D.

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Frog Data

• 40, 55, 64, 73, 78, 80, 85, 88, 89, 89, 91, 92,
  99, 103, 113, 113, 117, 125, 133, 150
• Paper ____________

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Review Terms

• Population Parameter
• Sample Statistic
• Margin of Error
• Confidence Level
• Confidence Statement

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Review Concepts

• For estimating population proportions how are ME
  and Sample Size related?
• What affect does increasing the sample size have?
• Does it matter the size of the population?

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Homework Concepts
Sample Surveys

• Sampling Errors
• Random Sampling Errors
• Using Bad Sampling Methods
• Undercoverage
• Nonsampling Errors
• Processing Errors
• Response Errors
• Nonresponse Errors
• Poor Wording

Q How does ME in a CS relate to sample error?
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Homework Sample Surveys

• More complicated sampling methods than the SRS
• Stratified Sample
• Definition _______________________
• Procedure ______________________
• Read Ex. 7 8, pg 58-59.
• Describe a mixed sampling method for telephone
  surveys (Hint Ex 9, p 60)

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Homework Sample Surveys

• Stratified Sample
• Definition
• Procedure
• Probability Sample
• Definition
• Example

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Hand-in Homework

• Draft a survey that helps you find out the types
  of math and/or statistics examples that interest
  students.
• New Homework
• Read survey from all other students.
• Think about how you might change your survey.
  Make Changes. Keep the survey to 1 page.

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Chapter 7

• Institutional Review Board (IRB) at MTSU
• MTSU IRB Form
• http//www.mtsu.edu/sponprog/downloadableforms.ht
  ml (click IRB Form)

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IRB Review

• Two Type of Reviews
• Expedited Review
• Full Review
• Informed Consent

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IRB Homework

• Go to IRB Form website
• Either save or print (thus either email or fax)
  the IRB form.
• Complete a rough draft of the IRB form for our
  Favorite Student Example Survey.
• Bring a printout to next class.

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Experiments
Chapter 5

• Terms to Know
• Subjects
• Response Variable
• Explanatory Variable
• Treatment Variable

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Experiments
Chapter 5

• Terms you wish you did not need to know
• Lurking Variable
• Confounding Variables

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Experiments
Chapter 5

• Randomized Comparative Experiment

Randomize (Results in groups of subjects that
are similar in all respects Before treatment is
applied.)
Apply Treatment (Other influences operate
equally on all groups)
Result (If there is a difference, it is due to
the treatment.)
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Experiments
Chapter 5

• Words to the Wise
• Control
• Randomize
• Have a large enough sample size
• Term to Know
• Statistically Significant

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Experiments
Chapter 5

• Sometimes we can only Observe
• Observational Studies vs. Experiments
• Explain the differences ( p. 79-81)

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Real-World Experiments
Chapter 6

• Term
• Placebo
• Placebo Effect
• Double Blind Experiments
• Issues
• Refusals, Nonadherers, Dropouts
• What generalizations can be made?

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Real-World Experiments
Chapter 6

• Completely Randomized Design
• Matched Pairs Design
• Block Design (Randomized Block Design)

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Homework
Chapter 6

• Read Chapter
• Chapter 6, end of the chapter problems
• Page 102
• 3, 7, 9, 11, 17, 19

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Homework Review

• Ch 3 Read. Work problems
• Ch 4
• Read. Page 61, Problems.
• Hand-in design survey
• Ch 7 Read chapter
• Ch 5 Read chapter carefully
• Ch 6 Read. Work problems.

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Chapter 8 Measuring

• Two types of Validity
• Measurement Validity
• Predictive Validity

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Chapter 8 Measuring

• Errors in Measurement. What is the formula?

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Chapter 9 Do the Numbers Make Sense?

• Consistent?
• Plausible?
• Correct arithmetic?
• Hidden agendas?
• ???