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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 <[log in to unmask]>
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


On Fri, 8 Apr 2005, Angie Cope, American Geographical Society Library
UWM wrote:

> ========================================================================
>
> 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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