12.2 Bending Curves to make them straight (with logarithms)
Basic Idea: Taking the logarithm of a set of data can fix uneven spacing issues.
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Look to see whether the x or y axis is having a spacing issue
Take the logarithm (natural or base 10) of the problematic axis/data set
Redraw Scatterplot to see if you have fixed the issue
Write equation of LSRL using the logarithm in the correct place
Option 1: Curving upward. Use an exponential model. Issue is in the spacing of the y axis
Graph x vs. ln y basically. Check it is linear and that the residual plot has improved
Option 2 (uncommon) Curving downward. Logarithmic model. Issue is x spacing.
Graph ln x vs. y. Check it is linear and that the residual plot has improved
Option 3: graph is scattering and residual has a fan. Issue in BOTH x and y
Graph ln x vs ln y. Check it is linear and that the residual plot has improved