NetNews Usenet Archive 1992 #23/NN_1992_23.iso/spool/sci/crypt/3828

Internet Message Format | 1992-10-16 | 1.7 KB

Xref: sparky sci.crypt:3828 alt.security:4582
Newsgroups: sci.crypt,alt.security
Path: sparky!uunet!infonode!ingr!b30news!craig!craig
From: [e-mail] (Craig Presson)
Subject: Re: Letter Frequency
In-Reply-To: [e-mail]'s message of 15 Oct 92 15:32:21 GMT
Message-ID: <[e-mail]>
Sender: [e-mail] (Usenet Feed)
Reply-To: [e-mail]
Organization: Intergraph Corporation, Huntsville, Alabama
References: <[e-mail]> <[e-mail]>
Date: Fri, 16 Oct 1992 17:55:33 GMT
Lines: 53

   [e-mail] (Rich Holland) writes:

   >I'm in dire need of a letter frequency chart for the English language.  I
   >remember as a kid reading books on basic cryptanalysis and seeing these
   >charts of the most frequently used letter (like "E" is most often used,
   >then "S" or "R" or something, etc).  I don't remember the order, but now
   >I need it.  Anyone got a copy of a table of something like this online?

   >If not, got a source where I can go look it up quick?

The frequency distribution that you get varies somewhat depending on
your source of text. Here is the table from Appendix C of Sinkov:

(#'s per 1000 letters)

E 130 T 93 N 78 R 77 I 74 O 74 A 73 S 63 D 44 H 35 L 35 C 30 F 28

P 27 U 27 M 25 Y 19 G 16 W 16 V 13 B 9 X 5 K 3 Q 3 J 2 Z 1


You get something a bit different if you just run a frequency test
on the dictionary (maybe I have an odd dictionary, too):

$ freq < /usr/dict/words | sort +1 -nr | pg
E 36119
A 30747
I 26179
R 23702
O 22767
T 22545
N 22412
S 22094
L 17688
C 17458
D 13054
U 10767
M 9780
B 9231
P 8539
H 7922
G 7817
Y 5766
F 3946
V 3285
K 3046
W 2603
Z 1041
X 862
Q 627
J 626


-- Craig