February 2005

Download this layer: ESRI Shapefile
(includes ArcGIS 9.0 LYR layer file and ArcView 3.x AVL legend file)
View this datalayer in an online map


This dataset contains points which represent locations of all libraries currently registered with the Massachusetts Board of Library Commissioners (MBLC). MassGIS created the layer from a list received from the MBLC. The list was current as of October, 2004, and contained the addresses and a few other related attributes for every library that currently meets the MBLC eligibility requirements for registration with the state (see http://mblc.state.ma.us/mblc/regional/membership/eligibility.php). Please note that not all libraries in the Commonwealth are compliant with these requirements, and therefore were not included in the list. If a library appears to be missing from the dataset, it is not registered with the MBLC as of October, 2004, and needs to do so to be considered in future updates.

In ArcSDE the layer is named LIBRARIES_PT.


The initial list of 1763 libraries was formatted by MassGIS staff and submitted to an in-house customized version of MassGIS' MapInfo MapMarker geocoding engine/application. Any unmatched addresses were then submitted to a 2nd round of geocoding using ESRI’s ArcMap v9.0 software and an Address Locator (geocoding service) using attributed street information from GDT. These two methods accounted for all but 31 of the libraries in the list. Those 31 libraries were then located through online research and phone calls to staff at the libraries or local officials. Finally, any library listed as being part of a K-12 school was compared to the existing MassGIS Schools datalayer, and where a match was found, those points were shifted to coincide with the school locations. In the end, a 100% match rate was achieved. MassGIS did not attempt to reconcile any spelling errors, missing or erroneous address information, or truncated values. Please note that points located strictly through geocoding methods (see PT_SRC attribute) may not be positioned so that they match their true location as seen on ortho imagery.


Each library point has the following attributes:
ID Numeric ID value. This value was arbitrarily assigned by MassGIS and does not reflect any official library ID.
OFFICE If the library is part of a larger institution, this field notes which institution it belongs to. If a public library, this field contains the name of the town.
NAME The formal name of the library, if it has one. If no formal name exists, the value “Library” is used.
ADDRESS The address of the library. May represent the mailing address or the physical address. No effort was made to differentiate between the two.
ADDRESS2 If the library has a secondary address, it is listed here.
TOWN The city or town in which the library is located.
STATE Always “MA”. This field was kept intact for automated addressing purposes.
ZIP 5-digit postal ZIP Code. Not all records have known values.
REGION Region of the state, as classified by MBLC.
 Type of library, including:
Public – A public library, administered by the local government.
Academic – Belonging to an institution of higher education.
School – A library that is part of a K-12 school.
Special-Corporate – Libraries owned and run by private corporations.
Special-Institutional – Includes prison libraries and certain special collections.
Special-Law – A legal library that is part of an institution of law. Does not include law school libraries.
Special-Medical – A library that is part of a medical institution or hospital.
Special – Covers a wide range of libraries not assigned to the other categories. Includes non-profit, religious, government, and cultural interests.
 Describes the method used to determine the geographic point location of the library. Domain values are as follows:
MGIS_GC – Points derived from in-house MapInfo Mapmarker geocoding application.
GDT_GC – Points derived from a geocoding service using GDT roads and ESRI ArcMap software.
HOSPITAL -  MassGIS' Hospitals layer used with color ortho imagery as reference to manually adjust library point.
MANUAL – Points derived from heads-up digitizing on 1:5000 scale color orthophotography, web research, and dialogues with individuals familiar with library location.
PRISONS - MassGIS' Prisons layer used with color ortho imagery as reference to manually adjust library point.
SCHOOLS – Points derived from MassGIS Schools datalayer.
CURR_AS_OF Date that data is considered to be current through. Represented in MM-DD-YYYY format. (i.e. 10012004 = October 1, 2004).


MassGIS maintains this layer. Any questions about the accuracy of the attribute data should be directed to Dianne Carty at dianne.carty@state.ma.us at the MBLC. Any questions about the geographic components and procedures should be directed to Dan Marrier at daniel.marrier@state.ma.us at MassGIS.

Last Updated 2/3/2005