Friday, March 25, 2011

Apology to Dr. Hartnett

I have discovered the nature of an error in a previous post (Quantized Redshifts. VIII. An Uncommon Power Spectral Density "Blooper") concerning the paper by Hartnett & Hirano, "Galaxy redshift abundance periodicity from Fourier analysis of number counts \$N(z)\$ using SDSS and 2dF GRS galaxy surveys", hereafter labelled HH2007.

My error was that I claimed the x-axes were incorrectly labeled when Hartnett converted them from 'frequency space' to his '\Delta_z space'.  These graphics were NOT mislabeled.

I've deleted the content of the original post and set a link to this post, since the great majority of the post was on the erroneous graphic plotting claim.  Other issues with HH2007 will be examined in a future post.

How did I make the error?
  • This error was one of those 'flashes' of 'insight' that occurred only about a week before I wrote the post.  That in itself should have made it suspect.  It did not receive the: idea - examine - walk away for a few weeks - reexamine - chat about with others - repeat (2 or more times) that other material in HH2007 had received.
  • I have read HH2007 at least 3 or 4 times.  ALL the other critiques of the HH2007 analysis have actually been under development for several years, going through the analysis cycle above several times for verification.  If the Delta_z problem had been real, the idea that I would not have noticed it earlier is a bit unlikely.  I should been bothered by that.
  • Customarily, plots are posted with the low value to the left end of the axis, whereas Hartnett (correctly) plotted the large value of Delta_z in Figure 5 of HH2007.  The prejudice of the customary axis direction was reinforced in casual examination of the graph on a small laptop screen where font antialiasing made some of the exponents in the axis scale unreadable and I failed to zoom-in on the graphic for a better look.  Several other non-standard notations for cosmology and power spectral in HH2007 contributed to confusing the underlying concepts as well.
  • Having read so many redshift-space analysis papers it is entirely possible that some of the graphics actually became confused with graphics in other papers and a quick examination of HH2007 graphics failed to fully register.
  • I hurried the analysis, trying to meet a self-imposed schedule of one post per week.  I allowed that to rush me into preparing the post without carefully checking the graphics in question beforehand.  
What changes do I intend to make to prevent the problem from happening again?
  • No more one-post-per-week schedule, especially for detailed analysis posts.  This blog is a part-time project and some of the ideas explored cannot be examined quickly but require careful examination.  Note that it is the pseudo-scientists in the comments of this blog who often try to push me to adhere to their time frame and in this case I foolishly took their bait.
  • I've wanted to do this for a time and have numerous individuals whom I have consulted on occasion for reviewing material and ideas.  I'm going to explore making that a more regular practice.
I doubt these changes will totally eliminate the possibility of an error, but it will reduce it.

I suspect there are some who will attempt to exploit this admission, so why am I doing this?  I work in a technical field were there are absolute standards of success and failure.  Those who learn from their mistakes and continue on, who don't dogmatically hang on to delusions that they are always right when the evidence is against them, have far more professional success. 

Depending on reactions, I may apply some different standards to comment moderation for a time.

11 comments:

Rick DeLano said...

Quite to the contrary Dr. Bridgeman. I think your apology is quite commendable.

The mere fact that you couch it in such defensive terms ("Note that it is the pseudo-scientists in the comments of this blog who often try to push me to adhere to their time frame and in this case I foolishly took their bait")-- only mitigates, but does not overcome, the commendability of the act.

It is good that the review continues, since the important work of Drs. Hartnett and Hirano continues to stand as a very serious challenge to the *philosophical* (not scientific) preference known as the Copernican or cosmological Principle.

The fact that this principle is indeed the very basis of cosmology, and is indeed now in the gravest observational question, makes some folks happy and some folks mad.

But that battle will certainly continue.

My congratulations to you for your apology.

Robert said...

Dr. Bridgman,

Thank you for being courageous enough to admit your error. I commend you for that. There is only one problem, however. In your admission you say "I discovered an error..." This gives the impression that you yourself poured over your work and discovered an error. Actually, you didn't "discover" it; it was told to you on our website in the article "More Trouble in Tom's Bubbles." Yet you didn't even acknowledge our article or our website as giving you that crucial information. Not exactly what I would call telling the whole truth, Dr. Bridgman. Care to rectify this?

The web address is:

http://www.galileowaswrong.com/galileowaswrong/features/AnwswerToBridgman.pdf

Robert Sungenis

W.T."Tom" Bridgman said...

I had given that article only the briefest of examination, not going for details (part of the reason I made the original mistake).

Actually, I have had some email correspondence with Hartnett and was re-reading his emails. There was some confusion about HH2007 final published form, which I had gone to check and realized my error.

Anonymous said...

It is indeed commendable that you admitted a mistake. But I don't think it is fair to compare it with others who "dogmatically hang on to delusions".

The mislabelled axes are a very specific error. An incorrect paradigm is more than a single correctable error.

I am sure that if you found a mislabelled creationist chart, it would be duly corrected.

We could turn this whole thing around, and argue that scientists who don't credit any part of a fringe theory, are as dogmatic as those who hold on to it in their entirety.

James said...

Dr. Bridgman,

You state the following: "I work in a technical field were [sic] there are absolute standards of success and failure." As a general reader, who nevertheless is fascinated by your blog, please allow me to ask you: 1) how exactly you would define your technical field, and 2) what exactly are its absolute standards of success and failure and where can those standards be seen to be precisely set out in the field's literature if indeed they are.

Thank you very much for your anticipated response. May you always seek to find the truth and be rewarded for any and all your efforts carried out in humility and good faith.

Sincerely,
James Phillips

W.T."Tom" Bridgman said...

To Anonymous:
I'm not clear what you have in mind for "scientists who don't credit any part of a fringe theory". I can think of several examples of science that started out rather "fringy" and is now credited, Birkeland currents for one.

Many supporters of far fringe science today often don't realize that many of their claims were explored (and dismissed) sometimes decades before their claims.

Electric Universe supporters claim any mention of electric fields in space are evidence for their more outragous claims, ignoring the fact that electric fields in space were being explored by astronomers even before the term 'plasma' was coined by Langmuir.

Then there is those fringers who happen to get the 'right' answer for the wrong reasons. If I compute 16/64 by cancelling the '6' above and below, I get the right answer. Does that mean my methodology is correct?

Was there a particular claim you had in mind?

W.T."Tom" Bridgman said...

To James,

Over the years, I've worked in a range of technical fields, from business programming to support positions for some space missions, though nothing mission critical. My current position involves assembling many scientific datasets in an accurate context for wider release. Where were the spacecraft when they took the data, where will they be when they take the data, what instruments were/will be looking where, etc.

In technical fields, success and failure are defined by if something works, or not. Did your spacecraft make it to orbit, or to another planet, based on the calculations (using Newton's laws and gravity) that were done years earlier? That's an absolute measure of success or failure.

The knowledge base I rely on for verification, in addition to project scientists, are textbooks, and other data sources.

James said...

Dr. Bridgman,

Thanks for your reply; much appreciated. I hope you can help me out on the following as well. Is it true that N.A.S.A. uses the geocentric model rather than the heliocentric model and if so what is their rationale for doing so -- if you know. I have not received any answer from N.A.S.A. regarding this.

JP

W.T."Tom" Bridgman said...

To James:

Depending on how you sent and worded such a query to NASA, it could have ended up anywhere from someone's spam email box to still working it's way through the system.

I started composing the response to this and found it quickly turning into something more appropriate for a blog post. I'd like to finish it up as a blog post, hopefully in the next week.

Anonymous said...

Dear Mr. Bridgman,

you wrote:

"Other issues with HH2007 will be examined in a future post."

Have you already written such a post?

Kind regards!

W.T."Tom" Bridgman said...

To Anonymous,

Hartnett was claiming connection to a cosmology by Carmeli in 2006 (see Carmeli's Cosmology Fits Data for an Accelerating and Decelerating Universe Without Dark Matter or Dark Energy).

Then he moved to Hirano in 2007.

Is he still using the Hirano model or has he moved to someone else?