Computer vs Algorithm

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

I am certain that Cochran has validated their model as well as, or better than, anyone has. That is not MY point. My point is that they have an obscure and unexplained and unacceptable set of internal routines that decide when you should do what during your ascent, whether that is convenient or even possible or not. Perhaps that works for Navy divers who really have no choice. It does not work for me, and I have a choice.
Curious have you ever dove or owned a Cochran dive computer?
Thank you
Have a great day!
Safe Diving
John
 
This is my last post on the subject:

If you read the above posts and paper uploaded, you will know that Cochran has access to all scientific studies, probabilistic model software (dive planner) and implementations from the Navy- plus the experiences of Thalmann Algorithm implementation, validation and verifications . Cochran can use all, including all man tested dives and use the same procedure as describe as “the gold standard” (NAVY) made on every validation (and it can be applied on the civilian version).
Thanks to all and safe dive!
C

Right. The point of my post that you quoted was that another poster in this thread implied that the Cochran algorithm was not "scientifically validated" like the Buhlmann ZHL-16B/C algorithm has been. I asked my question because I was thinking that the algorithm(s) Cochram computers use HAS been "scientifically validated" in a way that is comparable to Buhlmann.

I also made the point that my issue with Cochran computers is not the validation of the algorithm. It's that I want to use independently developed software to do dive planning and have some confidence that my dive computer results will match my plan.
 
I also made the point that my issue with Cochran computers is not the validation of the algorithm. It's that I want to use independently developed software to do dive planning and have some confidence that my dive computer results will match my plan.

Cochran Undersea Technology Or join the Navy?

As to ‘independently’ does that matter? Wouldn’t you rather be sure it matched rather than hope Ross or the OSTC folk chose the same rules as Shearwater?
 
Right. The point of my post that you quoted was that another poster in this thread implied that the Cochran algorithm was not "scientifically validated" like the Buhlmann ZHL-16B/C algorithm has been. I asked my question because I was thinking that the algorithm(s) Cochram computers use HAS been "scientifically validated" in a way that is comparable to Buhlmann.

The algorithm I use in my Buhlmann dive computer seems to me to have been “scientifically validated” to the same extent as my C++ implementation. That is not at all. Compared against Ross’s perhaps. At least mine can work without GF so Buhlmann’s own work might apply. How do we know that a low (ish, not 20 but say 50) GF lo is not a terrible idea? We guess, we watch what happens to other people. We don’t conduct proper manned trials though. The US Navy did for the Thalmann one used in the Cochran though.
 
As to ‘independently’ does that matter? Wouldn’t you rather be sure it matched rather than hope Ross or the OSTC folk chose the same rules as Shearwater?

I write software for a living. I would rather have a source to compare against that was independently developed.

I freely admit that I am relying to an extent on "crowd-sourced quality control" in that. Meaning, what I do has some element of confidence that comes from thinking that if the dive planning software I use doesn't match the Shearwater implementation in the Perdix, somebody would have discovered that by now and I would have heard about it. But, I don't rely completely on that.

It is also why I typically run my final plan in both Multi-Deco and Subsurface. I want to make sure those two match each other.

It is also why I do technical dives using a Perdix and a Seabear H3. "Trust, but verify." :D

If my computers don't agree during a dive, I will fall back to my wet notes produced via accord between M-D and Subsurface and use whichever seems to be the most conservative of the 3 (as it is very unlikely that either computer would actually agree with my wet notes, since they are based on a square profile or square levels within a multi-level profile).
 
I write software for a living. I would rather have a source to compare against that was independently developed.

I freely admit that I am relying to an extent on "crowd-sourced quality control" in that. Meaning, what I do has some element of confidence that comes from thinking that if the dive planning software I use doesn't match the Shearwater implementation in the Perdix, somebody would have discovered that by now and I would have heard about it. But, I don't rely completely on that.

It is also why I typically run my final plan in both Multi-Deco and Subsurface. I want to make sure those two match each other.

It is also why I do technical dives using a Perdix and a Seabear H3. "Trust, but verify." :D

If my computers don't agree during a dive, I will fall back to my wet notes produced via accord between M-D and Subsurface and use whichever seems to be the most conservative of the 3 (as it is very unlikely that either computer would actually agree with my wet notes, since they are based on a square profile or square levels within a multi-level profile).
Truly, you are the man with two watches :)

Segal's law - Wikipedia
 
Ha! So far, my two watches always read exactly* the same!

 

Back
Top Bottom