Many LibraryData reports display title-level data in broken out by ISBN Clusters. This differs from SalesData, which reports data at a per-ISBN level. This page will help you understand why ISBN clusters are used, and answer some common questions about ISBN Clusters!
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For example, if we're looking at the cluster for Pride and Prejudice, you can see that each of libraries 1, 2, and 3 have different ISBNs in their Record. Library 1 has one ISBN in common with Library 2, and Library 2 has one ISBN in common with Library 3. Those common ISBNs are used to create the ALL Libraries ISBN cluster for this title, pulling in all of the ISBNs from these three library records. As additional libraries' data joins the ALL Libraries Panel, the ALL Libraries ISBN cluster grows based on the common ISBNs in the libraries' records.
| Library 1 | Library 2 | Library 3 | ALL Libraries |
|---|---|---|---|
| 9780141199078 | 9780141439518 | 9780141439518 | 9780141439518 |
| 9780755331468 | 9780679783268 | 9780679783268 | |
| 9781593083243 | 9780141199078 | ||
| 9781904633013 | 9780755331468 | ||
| 9781551110288 | 9781593083243 | ||
| 9780679783268 | 9781904633013 | ||
| 9780679601685 | 9781551110288 | ||
| 9780679405429 | 9780679601685 | ||
| 9780307290922 | 9780679405429 | ||
| 9781853268335 | 9780307290922 | ||
| 9781853268335 |
What do ISBN clusters include?
Often ISBN Clusters include different editions of the same work. These can include different formats, like a paperback, hardcover, and mass-market edition, or editions released by different publishers. Libraries don't necessarily own copies of each ISBN in the ISBN Cluster - old ISBNs may have been weeded from the collection, or other ISBNs may have been added via bibliographic data imports to a library's ILS. This is why you may also see NCR editions' ISBNs listed within a cluster.
Why am I seeing an ISBN cluster containing multiple works?
Some ISBN Clusters may contain ISBNs for different but related works. For example, occasionally all of the titles in a series or set may be clustered as a single work. Libraries can catalog ISBNs in a single record for many different reasons, and LibraryData displays the ISBN Clusters based on the data delivered to us by Libraries. Human error is always a possibility!
If you believe we should review an ISBN cluster and work with a library on adjusting their catalog record, you can submit feedback on a cluster by clicking the "What are ISBN Clusters?" button on the Book Activity results for any cluster.
Individual Library clusters and the ALL Libraries cluster
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An informational box on the results page of all reports will tell you which aggregate's ISBN cluster you're viewing.
Why am I seeing so many different clusters in the search results?
The search bar looks for any clusters matching your search term in the title, series, subtitle and contributor name fields of the bibliographic data. It's also the case that there can be multiple clusters for the same work, if there are no ISBNs in common between multiple libraries' records for the work. The results are ranked by the most active cluster in the most recent week.
How do ISBN clusters work in SalesData?
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