Writing is a crucial skill of in-house lawyers (See my post of Feb. 5, 2009: writing with 6 references.). Software can analyze a person’s writing and suggest how to improve it. One common method describes a document in terms of the school level need to understand your prose. Seven tools that do exactly that are available on Readability.Info.
Not surprisingly, I directed the site to look at a recent patch of my posts. What follows are the explanations of the formulas that produced these scores, which I took from the website of Readability but shortened and edited.
The Kincaid Formula, developed for Navy training manuals, ranges in difficulty from 5.5 to 16.3. It is probably best applied to technical documents, much like mine are probably technical (The formula is 11.8*syllables/wds+0.39*wds/sentences-15.59.). My Kincaid was 13.5.
Automated Readability Index (ARI) is typically higher than Kincaid and Coleman-Liau, but lower than Flesch (4.71*chars/wds+0.5*wds/sentences-21.43). My ARI was15.7 (a junior in college?), higher than Kincaid.
Coleman-Liau Formula usually gives a lower grade than Kincaid, ARI and Flesch when applied to technical documents (5.89*chars/wds-0.3*sentences/(100*wds)-15.8). My Coleman-Liau was 13.3.
Flesch’s formula is based on school texts covering grades 3 to 12. The index is between 0 (hard) and 100 (easy); standard English documents average 60 to 70. (206.835-84.6*syll/wds-1.015*wds/sent). My Flesch Index was 48.0, so on the difficult side.
Fog Index gives a school grade. A level above 12 indicates the writing sample is too hard for most people to read (0.4*(wds/sent+100*((wds >= 3 syll)/wds)). My Fog Index was 16.9 so I apologize to all readers who can’t make sense out of what I offer.
Lix formula employs a mapping table as well (wds/sent+100*(wds >= 6 char)/wds). My Lix was 56.0, which translates to 11th grade.
SMOG-Grading gives a school grade (square root of (((wds >= 3 syll)/sent)*30) + 3). My SMOG Grading was 14.0, or mid-way through college.
Put simply, my writing style demands a lot from readers. But then, it should, because you are all smart and well educated!