EDF 5400

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EDF 5400

• Tuesday, August 3

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t-Test with Correlation Coefficient...
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t-Test with Correlation Coefficient...
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If r .75 and n 5 ...
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If r .75 and n 5 ...
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If r .75 and n 5 ...

• SPSS Illustration

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2nd Illustration t-Test with Correlation
Coefficient...

• High school data Correlation of motivation with
  test scores (males)
• Graphics
• Correlation and p-values

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Establishingconfidence interval for ?

• Lower Limit ? ? ? Upper Limit
• Using r ? 1.96 ?r will not work because
  correlation coefficient is not interval
• Fisher Z transformation (Table E, p. 625)
• Confusion between z and Z
• Transformation more significant with larger
  values of r
• Handling of negative values
• Steps in computing confidence interval

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Computing by hand confidence interval for ?

• Recall how we use the Fisher Z transformation
• If r .75 with n 5

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Computing by hand confidence interval for ?

• Recall how we use the Fisher Z transformation
• If r .75 with n 5

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2nd example of computing confidence interval for ?

• Correlation between motivation and reading scores
• If r .2106 with n 600

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Computing by hand confidence interval for ?

• Correlation between motivation and reading scores
• If r .2106 with n 600

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Using Excel to compute confidence intervals for ?

• Excel Illustration on EDF 5400 Web Site

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Parametric versus Nonparametric Statistics.....

• Assumptions
• Level of scaling
• Statistical efficiency
• Availability of computer programs
• Illustrate with SPSS
• Techniques unique to nonparametric and parametric
  statistics...

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Techniques unique to nonparametric and parametric
statistics...

• Unique to parametric techniques
• Regression
• Multiple correlation
• Factor analysis
• Unique to nonparametric techniques
• Analyzing categorical data (e.g., chi-square
  tests)

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Chi-square distribution
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Chi-square distribution
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Chi-square distribution
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SPSS DemonstrationChi-Square Test of
Independence(Academic majors of females versus
males)
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2nd SPSS DemonstrationChi-Square Test of
Independence(High School Data By race, number
of females versus males)