Stat 101: Lecture 2
Data
• Information
• Context is important
– Who? What? When? Where? Why?
and How?
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Who?
• Individual cases
– Each row of a data table
• Respondents
• Subjects
• Participants
• Experimental units
– U.S. Senators in 1999.
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Stat 101: Lecture 2
What?
• Variables
– Categorical variable
• State
– Quantitative variable
• Degree of conservatism
• Percent of vote
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Why?
• On February 12, 1999 the U.S.
Senate voted on whether to remove
a President (Clinton) based on
articles of impeachment. Why did
senators vote the way they did?
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When? Where? How?
• The data are available at
www.amstat.org/publications/jse/datasets/impeach.dat
• A description of the when,
where and how is given at
www.amstat.org/publications/jse/datasets/impeach.txt
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