add functions and collections

Author: Andrew McCluskey

_build/01/1/intro.html

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   Chapter 1: Introduction
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+pagenum: 33
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_build/01/2/why-data-science.html

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   Why Data Science?
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+pagenum: 34
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_build/01/3/Plotting_the_Classics.html

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   Plotting The Classics
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+pagenum: 35
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_build/01/3/subsection/subsections.html

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   Subsections
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_build/01/3/subsection/subsectiontwo.html

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   A second subsection page
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+pagenum: 37
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_build/01/what-is-data-science.html

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   What is Data Science
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+pagenum: 32
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_build/02/1/observation-and-visualization-john-snow-and-the-broad-street-pump.html

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   Observation and Visualization: John Snow and the Broad Street Pump
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+pagenum: 39
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_build/02/2/snow-s-grand-experiment.html

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   Snow’s “Grand Experiment”
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+pagenum: 40
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_build/02/3/establishing-causality.html

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   Establishing Causality
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+pagenum: 41
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_build/02/4/randomization.html

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   Randomization
-pagenum: 40
+pagenum: 42
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