Span for smooth

Question

When creating a scatter plot using the data investigations scatterplot tool, is there a formula used to figure out what the number for 'Span of smooth' should be?  Or is it smaller number rougher line, larger number smoother line?

Thanks,

Brad

JohnJPS · Accepted Answer

Hi @brad_j_crep,

The macro uses R behind the scenes; this article describes smoothing: http://docs.ggplot2.org/current/geom_smooth.html.  For "span" they have "Controls the amount of smoothing for the default loess smoother. Smaller numbers produce wigglier lines, larger numbers produce smoother lines."

Hope that helps!