About the Data in NDP
The Normative Data Project (NDP) pools data from several sources and provides an interface which makes it possible to join and merge these data in various ways to give new insights into the condition of libraries and their use.
The heart of the NDP is data from the integrated library systems of member libraries. These systems provide data on titles held, number of copies of each title, language, cataloging information, publication date, type of publication, and many other characteristics of their collections. In addition, these systems provide circulation information: Which titles circulated? When? To whom? Although there is no personally identifiable information on who borrowed what, the NDP does characterize borrowers by groups, such as Adult, Juvenile, and so forth. The NDP's circulation data, then, can generate the most popular DVDs borrowed by adults in the last quarter, for example.
In addition, in cooperation with GeoLib, census data from a library's service area can be examined to see major characteristics of the people the library serves. Click on the Case Studies button for an example of how one library mapped its service areas. Click on the White Papers button to read a related paper by Christie Koontz, the GeoLib director, on "Where do Our Library Customers Live (and Why Should We Care?")
Data from the US National Center for Education Statistics (NCES) are included. The edition of these data in the NDP is that done at the US National Commission on Libraries and Information Science (NCLIS) where the data were recompiled for use with trend analysis. Currently, two years of the State Summary Data are included, as well as two years of the Public Library Data File, which presents data on each of the more than 9,100 public libraries in the United States. Eventually, all years of these data will be available in the NDP. The data are also available on the NCLIS site in a variety of formats.
In addition, the popular ratios developed by NCES used to compile the State Rank Order Tables are available in the NDP, so that you can use these ratios to analyze individual libraries or groups of libraries.
The link to anomalies discusses anomalous data as a general problem. There are anomalies in the NDP data – with a new dataset that is as large as this one, how could it be otherwise? The literature on data anomalies provides some clues about how to vet the data for accuracy and reasonableness. The discussion on Vetting is a high level view of the matter, while Data Details presents how the concepts will actually be executed. Details, as the name suggests is intended to be quite detailed and to present a thorough, systematic discussion at the most granular level possible on what we are doing with the data to treat anomalies.
From a research perspective, the NDP represents most closely Use Studies, and this long and detailed literature is summarized on the linked page. Use studies focus on how the library is actually used, and they comprise a rich literature which we can examine with an eye to both adding to it and also using its conclusions to help test the NDP data. Are the conclusions of these use studies matched by the conclusions we draw from the NDP? So far, we have examined the conclusions about the dominance of English language materials in both ?? top10copies>holdings and ?? top10circs>circulations.