Statistics

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StatisticsChapters 7 8

• Contingency Tables
• Reading Assignment
• Ch 7. p. 246-253, 256-265,270-71, 275-78
• Ch. 8 291-95, 297-99, 306, 317-320

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Analyzing Contingency Tables 6

• Bivariate analysis measure the effect of one
  variable on another
• Variable having an effect on another independent
• Variable effected dependent variable
• P. 249, Skills 2
• P.253, Skills 3
• Avoiding pitfalls, p. 256
• Homework p. 257, Skills 4

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Interpreting Contingency Tables
5

• Finding patterns
• Interpretation has two-parts understanding the
  nature of the association and assessing its
  strength
• Understanding the nature of the association
  across the rows of the contingency table,
  differences in column percentages across a row
• P. 263discussion of table 7.5
• Understanding the strength of the association
  differences in percentagessize of difference
  small ?gap is small? association weak size
  large?gap large?association strong

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Models for interpreting contingency tables 2

• Box 7.1, p. 265
• Respondents who ltexhibit a particular
  characteristic of the independent variablegt are
  also more likely to ltexhibit a particular
  characteristic of the dependent variablegt than
  are respondents who ltexhibit another
  characteristic of the independent variablegt

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Elaboration 4

• Process of analyzing the relationship between two
  variables by using a third
• Gender gap Male/Female, Republican/Democrat
• Control Voted in 1992
• Follow SPSS p. 272

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Interpreting the contingency tables using a
control variable 4

• Patterns to explore see whether the variables of
  interest have a change in association, and look
  to see how the association changes
• If association weakens , association is spurious,
  i.e., something other than the independent
  variable accounts for the dependent variable
• Conditional association situation in which the
  strength or nature of the association between two
  variables changes across the categories of the
  control variable
• Analysis, p274 skills 12

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Writing up contingency analysis 4

• P. 276
• HW
• Skills 13
• P. 286/1,
• P.288/ 2,6
• Hand in p. 286/ 2 (Mon. 6/17)
• p. 288/ 3,7 (Thurs 6/20)

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