SCELC Blog

I've had a number of questions from members about the Overlap Analysis tool offered by Serials Solutions that members have access to through SCELC. The tool can be a great help in determining which databases are giving the most value (in terms of unique journals) for the money.

After clicking on Overlap Analysis on the Client Center Home Page you will be shown a list of all the databases that SCELC offers.

From here you have a number of options depending on which databases you want to compare. The buttons in the gray title bar allow for the different actions.

• Reset will bring the list of SCECL databases back to the initial state at any point in your session.
• Add will give you a screen where you can add any additional databases that Serials Solutions tracks to the list for comparison.
• Remove will bring you to a screen where you can check off which databases to exclude from the comparison.
• Run Analysis will execute the Overlap Analysis and include all the databases that are currently showing in the list.

Now for a working example.

Let’s say your institution wants to compare two databases. You’ll need to click the Remove button to go to the Remove page. Then de-select (uncheck) the databases you do not want to compare, or de-select (uncheck) everything to just make your selections on the Add page, depending on the method you want to use.

Once you’ve checked off the databases you don’t want and clicked the Remove button you'll be able to use the Add button to search for databases that you would actually like to compare. You can search by database title or get a list of databases from specific providers. On the list that shows up, select the databases you would like to add to your comparison list and click the Add button.

Then your list should appear with only the databases you want to compare. At this point click Run Analysis and the tool will begin working.

In order to understand your results, it is important to understand what all the numbers mean. Serials Solutions provides this key:

• Title Unique: Journals available in only one of your databases.
• Holding Unique: Journals available in more than one database, but without overlapping coverage dates.
• Total Unique: The sum of “Title Unique” and “Holding Unique” holdings.
• Full Holding Overlap: Journals available in more than one database. The coverage dates of the reference holdings are completely overlapped by at least one comparison holding.
• Partial Holding Overlap: Journals available in more than one database. The coverage dates of the reference holdings are only partly overlapped by at least one comparison holding.
• Total Holding Overlap: The sum of “Full Overlap” and “Partial Overlap” holdings.
• Title Overlap: Journals with overlap, but lacking enough information to define the overlap as “full” or “partial.”
• Total: The sum of “Total Unique” and “Total Overlap” holdings.
• Percent Full Overlap: Percentage of all holdings in a database that are completely overlapped by at least one other holding from another database.
• Percent Unique: Percentage of all holdings in a database that are either title unique or holding unique.

While there is no export function for this data, with your mouse, you can click and drag to select all of it and then copy and paste it into a spreadsheet for further use.