Correlation Song

lyrics copyright ©2013 by Lawrence Mark Lesser
sing to the tune of the English lullaby "Twinkle Twinkle Little Star" (Jane Taylor)

Are points near a line, or far?
What's the correlation, r?
If the fit supports a line,
Its slope and r would share the sign.
Twinkle, twinkle, you're a star:
Knowing stats will take you far!