File talk:ANS general picture.png
This image has an error; "some asymmetric binary system for Pr(0) = 3/4, Pr(1) = 1/4" does not match the diagram below it.
The system should be Pr(0) = 1/4, Pr(1) = 3/4.
Consider the example at the bottom of the right hand column, x=1,s=0->x=4,s=1->x=6,s=1->x=9 ... Intuitively, it is suspect that an encoding method would use 2 additional bits for a high probability symbol Pr(0)=3/4 and 0..1 additional bits for a low probability Pr(1)=1/4 symbol:
Encode s | x | Bits in x | Additional Bits |
---|---|---|---|
(Initial state) | 1 | 1 | NA |
0 | 4 | 3 | 2 |
1 | 6 | 3 | 0 |
1 | 9 | 4 | 1 |
1 | 13 | 4 | 0 |
1 | 18 | 5 | 1 |
Per the text on the Wikipedia entry for ANS, the densities are proportional to the probabilities. If the probabilities were really Pr(0) = 3/4 and Pr(1) = 1/4 then the diagram shows densities that are inversely proportional.
I'd be happy to update this image, however I don't have rights to overwrite it! -- Dominic P. Cooney (talk) 01:18, 20 June 2018 (UTC)
- Thanks, corrected. --Jarek Duda (talk) 07:49, 20 June 2018 (UTC)