The Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: information theory?
Replies: 83   Last Post: Dec 22, 2011 5:14 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
jim

Posts: 104
Registered: 7/19/11
Re: information theory?
Posted: Nov 4, 2011 3:41 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On Nov 4, 12:50 pm, VWWall <vw...@large.invalid> wrote:
> k...@kymhorsell.com wrote:
> > In sci.math Robert Wessel <robertwess...@yahoo.com> wrote:
> > ...

> >> Consider that high keystroke rates pretty much require chords, and a
> >> chord is most certainly not three or four random keys, pressed at
> >> different times and forces - rather they're a small subset of the
> >> possible combinations of keys within a hand-span (or two hand-spans in
> >> some cases), hit at the same time, and with the same force (in fact
> >> there are less than about 10,000 chords).  And just like English, you
> >> can't really have random sequences, or you'd just have noise.

>
> >> Still, 40bps intuitively feels a bit light, but not by that much. I
> >> expect that if Shannon said something like that, he was considering
> >> music to be more along the lines of a MIDI stream than a digitized
> >> sound file.

> > ...
>
> > Perhaps we could use spoken language as a guide to the auditory bidrate
> > we've evolved to process. As Shannon estimated, each letter in English
> > has only a couple bits of entropy, with normal reading speed (that
> > uses the auditory processing -- the reason you can't count the number
> > of words in a limerick without using your fingers) around 150 wpm.
> > Let's call that 25 bps.

>
> > 40 bps is then about the "square" (in log terms :) of our evolved language
> > processing speeds.

>
> > Maybe not such a bad estimate.
>
> > The same disparity is then seen between normal good voice compression
> > and the actually bitrate we operate on. I.e. 25 bps "back-end" processing
> > speed, yet voice compression being still 1000s of bps.

>
> > In some applications  over the years I've used speach-to-text and text-to-speach
> > over very low speed lines as a slap-dash compression method. With a bit
> > of a phoneme "nomenclator" it wasn't too bad. No doubt the idea is still in
> > use, but I don't think I've heard of it in preference to straight dsp methods.

>
> At the 1939 World Fair in New York City, Bell Telephone had an exhibit
> featuring the "vocoder".  An operator could synchronize speech by
> pressing "keys" on a console.  Bell thought the method could be used for
> "compressing" its telephone bandwidth requirements.
>
> As it turned out, bandwidth was not the limiting factor in future
> telephone growth.  Simple system changes like separating the low-speed
> "housekeeping" functions from the in-band "information" were implemented.


The cranks that work in signal processing are bandwidth obessed
with all
technology, so that's where digital signal processing, Turing
Machines, Lasers,
Holograms, miniature atomic clocks, Integrated Circuits, XML,
Optical Networks,
USB, LEDS, Flash Memory, Orbital Solar Energy, and post New York
Times
ergonomics all came from.


> I was involved in the testing of microwave frequencies in small circular
> wave-guide to allow for much wider band channels.  The need never
> evolved, and fiber optics replaced microwaves where it was needed.
>
> As far as I know, any "compression" system requires some means of
> "storing" information so that it can be processed.  This was just being
> developed during Shannon's time.  It's obvious that "digital" storage is
> easier and more flexible than analog.
>
> --
> Virg Wall




Date Subject Author
10/31/11
Read information theory?
Rich Delaney
11/1/11
Read Re: information theory?
Eric Jacobsen
11/1/11
Read Re: information theory?
Chris
11/1/11
Read Re: information theory?
Rich Delaney
11/1/11
Read Re: information theory?
jim
11/1/11
Read Re: information theory?
jim
11/1/11
Read Re: information theory?
Cindy
11/1/11
Read Re: information theory?
BJACOBY@teranews.com
11/2/11
Read Re: information theory?
jim
11/2/11
Read Re: information theory?
BJACOBY@teranews.com
11/2/11
Read Re: information theory?
jim
11/2/11
Read Re: information theory?
Cindy
11/2/11
Read Re: information theory?
jim
11/3/11
Read Re: information theory?
Cindy
11/1/11
Read Re: information theory?
BJACOBY@teranews.com
11/2/11
Read Re: information theory?
Les Cargill
11/3/11
Read Re: information theory?
Andrew Haley
11/3/11
Read Re: information theory?
gdewilde@gmail.com
11/2/11
Read Re: information theory?
Martin Brown
11/2/11
Read Re: information theory? (copyright question followup)
JohnF
11/2/11
Read Re: information theory? (copyright question followup)
Martin Brown
11/2/11
Read Re: information theory? (copyright question followup)
Martin Brown
11/2/11
Read Re: information theory? (copyright question followup)
Bernd Jendrissek
11/2/11
Read Re: information theory? (copyright question followup)
David Eather
11/2/11
Read Re: information theory? (copyright question followup)
Bill Unruh
11/24/11
Read Re: information theory? (copyright question followup)
J. Clarke
11/24/11
Read Re: information theory? (copyright question followup)
Martin Brown
11/25/11
Read Re: information theory? (copyright question followup)
Richard Outerbridge
11/25/11
Read Re: information theory? (copyright question followup)
Les Cargill
11/2/11
Read Re: information theory?
Rich Delaney
11/3/11
Read Re: information theory?
Martin Brown
11/2/11
Read Re: information theory?
Chris
11/2/11
Read Re: information theory?
robert bristow-johnson
11/2/11
Read Re: information theory?
Rich Delaney
11/2/11
Read Re: information theory?
VWWall
11/2/11
Read Re: information theory?
Richard Outerbridge
11/4/11
Read Re: information theory?
Frederick Williams
11/4/11
Read Re: information theory?
krw@att.bizzzzzzzzzzzz
11/4/11
Read Re: information theory?
jim
11/4/11
Read Re: information theory?
Jerry Avins
11/4/11
Read Re: information theory?
Greg Rose
11/5/11
Read Re: information theory?
Frederick Williams
11/5/11
Read Re: information theory?
Mike Terry
11/5/11
Read Re: information theory?
MrTallyman
11/5/11
Read Re: information theory?
R Kym Horsell
11/5/11
Read Re: information theory?
MrTallyman
11/5/11
Read Re: information theory?
unruh
11/5/11
Read Re: information theory?
krw@att.bizzzzzzzzzzzz
11/7/11
Read Re: information theory?
JW
11/7/11
Read Re: information theory?
krw@att.bizzzzzzzzzzzz
11/7/11
Read Re: information theory?
MrTallyman
11/7/11
Read Re: information theory?
krw@att.bizzzzzzzzzzzz
11/4/11
Read Re: information theory?
FigureItOut
11/6/11
Read Re: information theory?
jim
11/4/11
Read Re: information theory?
Rich Delaney
11/4/11
Read Re: information theory?
BJACOBY@teranews.com
11/4/11
Read Re: information theory?
Peter Webb
11/4/11
Read Re: information theory?
robertwessel2@yahoo.com
11/4/11
Read Re: information theory?
R Kym Horsell
11/4/11
Read Re: information theory?
Peter Webb
11/4/11
Read Re: information theory?
VWWall
11/4/11
Read Re: information theory?
jim
11/4/11
Read Re: information theory?
jim
11/4/11
Read Re: information theory?
Androcles
11/4/11
Read Re: information theory?
Martin Brown
11/4/11
Read Re: information theory?
Peter Webb
11/4/11
Read Re: information theory?
BJACOBY@teranews.com
11/4/11
Read Re: information theory?
Jerry Avins
12/21/11
Read Re: information theory?
Rich Delaney
12/21/11
Read Re: information theory?
Les Cargill
12/22/11
Read Re: information theory?
Richard Outerbridge
12/22/11
Read Re: information theory?
Martin Brown
12/22/11
Read Re: information theory?
Peter Webb
11/4/11
Read Re: information theory?
Androcles
11/4/11
Read Re: information theory?
Casper H.S. Dik
11/4/11
Read Re: information theory?
Bill Unruh
11/6/11
Read Re: information theory?
jim
11/7/11
Read Re: information theory?
jim
11/7/11
Read Re: information theory?
jim
11/8/11
Read Re: information theory?
jim
11/8/11
Read Re: information theory?
Michael A. Terrell
11/3/11
Read Re: information theory?
BJACOBY@teranews.com
11/3/11
Read Re: information theory?
Chris
11/3/11
Read Re: information theory?
Chris

Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© The Math Forum at NCTM 1994-2018. All Rights Reserved.