Post on 14-Feb-2017
Scaling in R &
ggplot + forecastEd Goodwin
Houston R Users Group
What is scaling?Scaling is when you need to transform a dataset to
another size scale…usually to analyze with a another data set
Example: comparing two survey datasets with different scoring mechanisms
It allows you to measure the relative effects of datasets on different scales
Let’s make some samples
How do we common-size our samples?
• With the scale( ) function
• scale( ) allows you to scale and center the data
Scaling
Divide all column values by the standard deviation
to arrive at a common scaling
Centering
Subtract all column values from the column mean to
get a common center value
Centered & Scaled
You could also do this yourself (z-transform)
Forecast + ggplot
Recent updates to Rob Hyndman’s forecast package include ability to use ggplot for plotting time series forecasts.
See http://robjhyndman.com/hyndsight/forecast7-ggplot2/ for more details
Using ggplot with time seriesuse autoplot( ) function with time series objects to create ggplot graphics.