Saturday, December 12, 2009
Almost nobody wants to see your Top 15 list: please use either a Top 10 or a Top 20 list
At the end of the year it once again is time to compile silly annual lists of “The Top N.” Where should you stop – at 10, 15, 20, 25, or 30? We all know that lists of 10 are commonly used by folks like David Letterman or Guy Kawasaki. If you need a somewhat longer list should it stop at 15 or go on to 20? My answer is 20. Lists of 15 apparently would be about ten times less popular, although I have no idea why this should be so.
Yesterday morning I did a series of Google and Yahoo searches on the quoted phrase “top N” where N was a number ranging from 2 to 30. I tabulated the number of search engine hits, and then plotted them (on a logarithmic scale) versus the number of items as is shown above. (Click on the plot for a larger, clearer view.) The Popularity was defined as the logarithm of the number of hits, so a popularity of 6 means 1,000,000 hits, a 7 is 10,000,000, and an 8 is 100,000,000 and so on. When you connect between the Popularity for 10 and 30 with a straight line, it goes almost directly through 20 and 25, but it is goes about a full unit (or ten times) above passing through the value for 15.
I also did a similar series of searches, for N at intervals of 5 over a range from 5 to 150. The following plot shows those results. “Top 100” was about as popular as “Top 10”, and Top 20 and Top 50 also were relatively popular. Forget about ever using “Top 105” - it was truly pathetic.
This research was inspired by finding a list of 45 Commandments of Public Speaking posted on December 9th by Susan R. Young at Get in Front Blogging. Based on the following plot a “Top 50” list would get about 70 times more hits than a “Top 45 list”.