Viewing Distribution
1. Building Histograms
>> Methods to create histograms
[Method 1] : Use Show Me
- Select [Measure] field --> click [Show Me] --> click the histogram thumbnail
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Edit bins : Right-click [Age (bin)] --> [Edit]
[Method 2] : In the Data pane
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Right-click [Measure] field --> select [Create] --> select [Bins] --> edit bins --> click [OK]
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Size of bins: Default value – Tableau suggested size
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Bin range:
- [a, b) a<= x < b
- For a bin size of 5, on data starting at 0:
[0, 4] – [5, 9] – [10, 14] … / [0, 5) – [5, 10) – [10, 15) …
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Binning a measure creates a dimension : [Age (bin)]
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Build the view:
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Drag [Age] to [Rows]
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Drag [Age (bin)] to [Columns]
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Change the aggregation of [Age] from Sum to Count
Change [Age (bin)] into continuous field [Age (bin)]
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Fix the tick marks to the bin size
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Right-click the x-axis --> click [Edit Axis]
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[Tick Marks] Tab --> [Major tick marks] --> [Fixed] --> [Every] : (size of bins)
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2. Building Box and Whisker Plots
>> Box Plot
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IQR: Q3 - Q1
Upper fence: Q3 + 1.5 * IQR
Lower fence: Q1 - 1.5 * IQR
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The bottom and top whiskers are not always the same length:
the whiskers will show the last data point that is within the 1.5*IQR
>> Methods to create box plot
[Method 1] In the Data pane
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[Columns] : [Dimension] field
[Rows] : [Measure] field
[Details] : [Dimension] field
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[Analytics] Pane --> Drag [Box Plot] to the view --> [Cell]
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Edit the box plot
[Method 2] : Use Show Me
- Hold [Ctrl] and select [Dimension] field and [Measure] field
- [Show Me] --> click the box and whisker icon
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Using the Marks card to adjust the formatting
- Mark Type : Circle
- Size & Color
