Spurious Correlations
What is a Spurious Correlation? A spurious correlation wrongly implies a cause and effect between two variables. For example, the number of astronauts dying in spacecraft is directly correlated to seatbelt use in cars: Use your seatbelt and save an astronaut life!Mar 3, 2016
Letters in Winning Word of Scripps National Spelling Bee
correlates with
Number of people killed by venomous spiders
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1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | ||
Letters in Winning Word of Scripps National Spelling Bee Letters (Scripps) |
9 | 8 | 11 | 12 | 11 | 13 | 12 | 9 | 9 | 7 | 9 | |
Number of people killed by venomous spiders Deaths (US) (CDC) |
6 | 5 | 5 | 10 | 8 | 14 | 10 | 4 | 8 | 5 | 6 | |
Correlation: 0.8057 |
Honey producing bee colonies (US)
correlates with
Marriage rate in Vermont
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1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | ||
Honey producing bee colonies (US) Thousands of colonies (USDA) |
2,652 | 2,622 | 2,550 | 2,574 | 2,599 | 2,554 | 2,409 | 2,394 | 2,443 | 2,342 | 2,498 | |
Marriage rate in Vermont Marriages per 1000 people (US Census) |
10 | 10 | 9.8 | 9.8 | 9.7 | 9.4 | 8.9 | 8.6 | 8.5 | 7.9 | 8.7 | |
Correlation: 0.937689 |
Example of Using Scale to Mislead
These are the exact same statistics just on a different scale. The first statistic has trimmed the bottom off the chart to make the change look alarming. (Top Drawer Teachers)