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Date: Fri, 8 Apr 2005
From: Mary Larsgaard <[log in to unmask]>
Subject: MAPS-L: RE: Records to Pieces Ratio

It seems to depend upon:
a. what kind of map collection one has:
is it a general collection with a heavy
topo-sheet population, or is it the
map collection of an historical society?

b. whether or not one analyzes monographic series.
Several years back, I had to come up
with some numbers for a retrocat project
here at UCSB, and decided I wouldn't
be analyzing monographic series
until after the exact-match retrocat was done.
So I used 1 title/10 pieces (which is what
I also used when I worked at the Colorado
School of Mines), and that's pretty close.

Mary


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>MAPS-L ** MAPS-L ** MAPS-L ** MAPS-L ** MAPS-L ** MAPS-L
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>Date: Fri, 8 Apr 2005
>From: Christopher Winters
>Subject: Re: MAPS-L: Records to Pieces Ratio
>
>A survey I did a few years ago suggested that at the University of Chicago
>Map Collection, there are almost exactly 5 sheets per title. The survey
>assumed that monographic series (like the USGS I series) would be
>analyzed, while sets of topos wouldn't be. I believe the survey was
>statistically fairly sound. We used a large enough sample so that the
>results are more than 99% likely to be accurate to within a few percent.
>But different map libraries have very different collections. The U of C
>Map Collection has a large number of one-sheet urban and geology titles.
>Libraries where sets of topos constitute a larger proportion of holdings
>will have a higher sheet-to-title ratio.
>
>Hope this is helpful.
>
>Chris Winters
>University of Chicago Library
>
>
>
>
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>> MAPS-L ** MAPS-L ** MAPS-L ** MAPS-L ** MAPS-L ** MAPS-L
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>> Date: Fri, 8 Apr 2005
>> From: Jenny Marie Johnson
>> Subject: Records to Pieces Ratio
>>
>> Hi.
>>
>> This probably is one of those questions that can't be answered --
>> although for some reason I vaguely remember reading or hearing a
>> discussion about it.
>>
>> Is there any kind of ratio that can be expected for the number of
>> bibliographic records to the number of pieces in a "typical," fully
>> cataloged map collection?  Is there any way of saying "Since we have
>> x,000 pieces we can expect to find y,000 map records in the online catalog?"
>>
>> I'm not expecting there to be a truly scientific ratio!  Commonsense,
>> wisdom from the ages, or folklore/urban myth -- all ideas will be helpful!
>>
>> Thanks!
>>
>> Jenny Marie Johnson
>> Map and Geography Librarian and
>> Assoc. Professor of Library Administration
>>
>> University of Illinois at Urbana-Champaign
>>
>
>
>--
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