The figures are interesting.  But if a tabulation of occurrences of ISBN is 
being used to indicate something, it's just as well to be aware of what they 
designate and how they may be related.  Since the qualifying text which may 
be recorded in MARC in association with the number is free text, it's 
difficult to use it as a basis for argument: I have read many a MARC record 
in which an ISBN for a multipart set was not qualified (in any way) with 
that information, and likewise many a record where ISBNs for constituent 
volumes had nothing to identify which parts the numbers had been assigned 
to; and sometimes nothing to show which number was assigned to hardback or 
paperback (or other special) binding.

But there's some history which also plays a part in helping us understand.

The standard book numbering movement got off the ground with a 9-digit 
number: 8 digits plus a check digit.  A few years later it became universal, 
and a tenth digit was prefixed: happily the English-language publisher group 
was assigned 0 as prefix, so the verification algorithm using the check 
digit remained valid. More recently ISBN has been merged into broader prduct 
numbering with additional prefix (mostly 978) added, and this time the 
verification of the check digit has to change.

The point is that, in terms of what appears on an item (and in the 
bibliograhic record), the 9-digit SBN, the 10-digit ISBN and the 13-digit 
ISBN may be functionally, if not formally, identical.  They can all be 
converted from one form to another -- indeed, OCLC has algorithmically 
created in WorldCat 13-digit equivalents for existing 10-digit numbers, 
irrespective of whether the physical items carry numbers in 10- or 13-digit 

A count of the number occurrences, as a resource for sketching a framework 
or making a preliminary assessment of its validity, surely ought to account 
for these equivalences?  They are, after all, the same identifier encased in 
different recognition and validation frameworks: they don't designate 
different bibliographic objects.

Hal Cain
Melbourne, Australia
[log in to unmask]

On Wed, 22 May 2013 11:14:06 +0000, Shlomo Sanders 
<[log in to unmask]> wrote:

>I don't think there is a need.
>Number with zero don't change.
>Number with one don't change.
>Some of those with two may actually be one.
>More than 2 is definitely more than 1.
>Sent from my iPad
>On May 21, 2013, at 21:23, "Tennant,Roy" 
<[log in to unmask]<mailto:[log in to unmask]>> wrote:
>Yes. The program is simply counting the number of 020 $a's it finds in
>each record. If necessary, it could be altered to count the two kinds
>On 5/21/13 5/21/13 � 2:28 AM, "Shlomo Sanders"
><[log in to unmask]<mailto:[log in to unmask]>> 
>Are you counting 10 digit and 13 digit as 2 different ISBNs?
>Experience the all-new, singing and dancing interactive Primo brochure
>-----Original Message-----
>From: Bibliographic Framework Transition Initiative Forum
>[mailto:[log in to unmask]] On Behalf Of Tennant,Roy
>Sent: Monday, May 20, 2013 22:33
>To: [log in to unmask]<mailto:[log in to unmask]>
>Subject: Re: [BIBFRAME] Instance of ISBNs in MARC records
>Corrected figures. The main difference is that the position of single
>instances and 4 instances switched.
>NO. of Recs ISBNs Percent
>230444194  0 77.71%
>55668178  2 18.77%
>4766652  1  1.61%
>3708352  4  1.25%
> 616623  3  0.21%
> 411230  6  0.14%
> 125715  8  0.04%
>  65796  5  0.02%
>  45304 10  0.02%
>  30155 12    0.01%