Scatter plot



•Relationship of two interval variables
•Correlation
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•Weight x height
•Unemployment rate x purchase power
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Three types of correlation in a scatter plot undefined



Scatterplot



outliers
overplotting


Log axis
•Solution when there is a lot of small values and a few high values
•Typical situation: population
•Problem: it does not work for 0 and negative numbers
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Right click here
a quantity representing the power to which a fixed number (the base) must be raised to produce a
given number (eg for 100 it is 2 because 10power2 is 100)
Excel leaves the labels as not transformed, but it change look of axis

Both axes logged
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Add point labels



•Overlays need to be managed manuály
•Use short names or abbreviations


Add lines
•Trend line
•Linear
•Exponential
•logarithmic
•Quartals
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Right click here
From minimum to average
From average to maximum

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Trend line
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Set of boxplots