The purpose of the Category Performance Comparison lane is to give you a tool with which you can compare your different categories or collections to each other to see which are performing the best, or worst, or that may be just as they need to be. The idea is to help you prioritize those areas of your library that might need more immediate attention, whether with an influx of titles, or (most often) the opposite.
Keep in mind, that these comparisons are ‘relative,’ meaning that this tool compares your categories to each other, rather than to some subjective ‘ideal’ performance. It measures each category according to circulations vs. units owned…so it essentially asks the question: “Is this portion of my collection sized according to its performance?” To provide an example: If your gardening titles make up 40% of your collection, but only accounts for 5% of your circulation… that collection is grossly over-sized. This tool provides a quick insight into such things.
Categories that would be considered “Overstocked” show up in the red portion of the graph. Those categories listed in the yellow portion of the graph would be considered “Understocked.” For example, if your Self-Help titles account for 5% of your stock, but accounts for 20% of your circulation, there’s a good chance that Self-Help would benefit from more space and more books. Those categories that show in green are closer to being ‘balanced,’ in that their size is commensurate with their circulation.
Within the graph, your larger categories are on the far right, and smaller categories are on the left.
On the vertical axis, your highest-circulating categories are at the top, with your lowest-circulating categories on the bottom row. The numbers indicate the number of categories contained in each section of the graph.
The categories listed in the upper right are basically your largest and best-circulating categories. Those in the lower right (in the red) are those that are, basically, bloated. One can assume that the person responsible for purchasing at this library assumes that those categories are popular and have purchased for them accordingly. Data suggests otherwise, however.
You can view your collection through a few different ‘lenses,’ including BISAC, Dewey, Age, Media Type (format), etc. Most of that information, like format, Age, or BISAC subject, etc. are all provided within the publishers’ metadata for each title. So, regardless of how you classify a title in your library, you can still see how your collection is portioned out according to, for example, fiction genres:
Or you can even see how, for example, different ‘sub-genres’ of Mystery titles you tend to own and circulate the best, or worst. To do so, simply click on “Mystery & Detective” to open that category.
Note that this creates a “Temporary Filter” that is applied to your other Analytics Lanes. So, you can dive in to your mysteries and immediately research what you might be missing, what could/should be weeded, upcoming titles, etc.
You can also get more detail about the performance and such for these categories. By clicking “Open Category Summary Report” in the upper right of the lane. This will bring up a “Category Performance Detail” chart.