The Flesch-Kincaid readability test
is a very simple metric that calculates how long the sentences
and how big the words used in a text are.

Complicated, long words used in scientific jargon will give
low readability scores.
Carelessly written text with run on sentences and lots of which
and that will score low on the readability scale.
Short sentences with simple words are considered more readable.

Toby Donaldson at SFU has an implementation of Flesch-Kincaid in python. I decided to check how the three chapters of the book score.

In a command prompt:

cat math/*.txt > /tmp/all_math.txt
cat calculus/*.txt > /tmp/all_calc.txt
cat physics/*.txt > /tmp/all_phys.txt


Then downloaded and installed

import flesch

math = open(“/tmp/all_math.txt”).read()
flesch.summarize( math )
Total # syllables: 26730
Total # words: 17719
Total # sentences: 1248
Flesch reading ease score (FRES): 64.8417724083
Flesch-Kincaid grade level: 11.7480791982

flesch.summarize( calc )
Total # syllables: 43247
Total # words: 28103
Total # sentences: 1634
Flesch reading ease score (FRES): 59.2303055328
Flesch-Kincaid grade level: 13.2762936474

flesch.summarize( phys )
Total # syllables: 42982
Total # words: 27984
Total # sentences: 1740
Flesch reading ease score (FRES): 60.6107049743
Flesch-Kincaid grade level: 12.8064754047

flesch.summarize( la )
Total # syllables: 24280
Total # words: 15074
Total # sentences: 972
Flesch reading ease score (FRES): 54.8681963758
Flesch-Kincaid grade level: 13.464711137

flesch.summarize( EnM )
Total # syllables: 30724
Total # words: 19138
Total # sentences: 1188
Flesch reading ease score (FRES): 54.7087328366
Flesch-Kincaid grade level: 13.6363072411

 

Its actually pretty accurate. The math chapter is
for people in high school. The Phys is 1st year
university level and the calculus seems to be
a little more advanced. Linear algebra with
words like “eigenvector” obviously wins as the
hardest thing.

Very cool.

EDIT: Just for comparison, I will now test my MSc thesis.

flesch.summarize( th )

Total # syllables: 61114
Total # words: 34436
Total # sentences: 1985
Flesch reading ease score (FRES): 39.1269891464
Flesch-Kincaid grade level: 16.1173708441

So yeah. I have some range.