The perils of misusing statistics

There has been a lot of reaction (here, here, here, here, and many more) on the blogs to an article on blogging in The Wall Street Journal. The article says:

It takes about 100,000 unique visitors a month to generate an income of $75,000 a year.

The author reacts to feedback at the end and states:

The question of how much traffic it takes to make a living also comes from the Technorati report. We say it takes "about 100,000 unique visitors a month to generate an income of $75,000 a year" and Technorati states those who had 100,000 or more unique visitors the average income is $75,000

The original source for the numbers is http://technorati.com/blogging/state-of-the-blogosphere/blogging-for-profit/

Among active bloggers that we surveyed, the average income was $75,000 for those who had 100,000 or more unique visitors per month (some of whom had more than one million visitors each month). The median annual income for this group is significantly lower — $22,000.

The huge difference between median and average says that there are a few very high numbers out there. It also says that if you are getting “only” 100,000 unique visitors per month, you will be getting a lot less than $22,000 since that is the median of all those getting 100000 or more uniques per month. Half of them are getting less than that amount.

It is good to know something about statistics when writing about them.

(Since its start, this blog has had 4124 page impressions and has earned me a grand total of 65 cents.)