Module%203.%20Time%20and%20Circumstance

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Module 3. Time and Circumstance

• Static vs. Dynamic Views

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Problems with the Static ViewThe Basic View
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Problems with the Static ViewThe Secular Trend
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Problems with the Static ViewPeriodicity/Seasonal
ity
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Problems with the Static ViewHow change unfolds
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Problems with the Static ViewHow change unfolds
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Problems with the Static ViewHow change unfolds
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Questions to Ask

• Is there a secular trend? Was it happening
  before any intervention?
• Is there periodicity by hour, day, week, month,
  quarter?
• How did change unfold?
• Sudden vs. gradual.
• Sustained vs. temporary.
• Are observations independent?

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(No Transcript)
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Is the bar chart showing dramatic before-after
change justified?
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For another perspective
Check out Carey and Lloyd Figure 4.1 (Static)
vs. Figure 4.2 (Dynamic) Pages 46-47
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Thought Provoking Question