When the Labor Department released its employment figures for January 2009, it subtracted an astounding 356,000 jobs from the overall count because it felt that small companies were quietly going out of business.

It couldn't prove this was really happening.

But the department's computers made that adjustment anyway -- and much more optimistic ones over the 11 other months of 2009 -- because something called the birth/death model instructed them to do so.

The model is a guess -- and a bad one, it turns out -- at how many companies too small to be reached in the official monthly survey are creating jobs (the "birth" part) or eliminating them ("death").  More here.