TIGER/Line 1997 README File
- What are the TIGER/Line Files
- What's New
- Using this CD-ROM
- Data Decompression
- Additional contents of the CD-ROM:
- Data Compression
- Known Problems and Anomalies with this TIGER/Line Data Set:
- Missing Zip+4 Records
- Address Anomalies in Puerty Rico and Queens, N.Y.
- Road Feature Anomalies
- Version Number Change
- Naming Standards in Record Type 1
- Questions and Additional Information
U.S. BUREAU OF THE CENSUS
Census TIGER(R) and TIGER/Line(R) are registered trademarks of the U.S. Bureau of the Census.
WHAT ARE TIGER/LINE FILES
The TIGER/Line files were created from the Census Bureau's TIGER (Topologically Integrated Geographic Encoding and Referencing) data base of selected geographic and cartographic information. TIGER was developed at the Census Bureau to support the mapping and related geographic activities required by the decennial census and sample survey programs. TIGER/Line files are made available to the public and are typically used by people to provide the digital map base for their Geographic Information System or mapping software.
This CD-ROM does not contain software to display or generate maps. Nor is the data on this CD-ROM in the form of a map image. To create maps with the data on this CD-ROM, one would typically use a Geographic Information System package or other mapping software. For information on how to use the TIGER/Line data with a specific package one should contact the company that produced the package. For information on companies that sell products that use TIGER/Line data or that provide various TIGER/Line-related services refer to the "Vendor's List" on the TIGER Page at the Census Bureau's World Wide Web site described below.
These TIGER/Line files were originally produced for use by the states participating in the Census 2000 Redistricting Data Program, Phase I, the Block Boundary Suggestion Program (BBSP) to verify their submissions to the U.S. Census Bureau. The 1997 TIGER/Line files include updates from the BBSP, the 1997 Boundary and Annexation Survey, and other Census Bureau programs that update the TIGER data base. It is important to note that even though each TIGER/Line file represents a whole county, all new features in existence may not have been added in this release. The extent of updates in any given county will vary by program, number of participants, type of participant, time of participation, and a given participant's degree of participation in a program.
Since the last release of TIGER/Line the city of South Boston, VA is no longer an independent city (county equivalent) and is now part of Halifax County. Therefore, there is not a separate TIGER/Line file for this entity. Also, the current geographic boundary information found in Record Type 1 reflect this change and one must use the information in Record Type 3 if it is necessary to create the boundaries as they existed in 1990.
Note that the CENBBSEL field in character position 129 on Record Type 1 in the BBSP Annotation TIGER/Line is now named CENSUS1. The BBSPPART field in character position 130 on Record Type 1 in the BBSP Annotation TIGER/Line is now named CENSUS2.
We have reorganized the contents of two of the CD-ROMs (which States are included) to make the groupings of States more geographically rational. For this version of TIGER/Line New Mexico was moved to Disk 4 and Arizona moved to Disk 5.
USING THIS CD-ROM
The 1997 TIGER/Line CD-ROMs contain digital cartographic data files and related documentation. The files include the counties, parishes, boroughs, census geographic areas, and equivalent entities for each state (or territory, and so forth) participating in the BBSP program. The data is organized in subdirectories by county (or county equivalent) within a state. Each state subdirectory is named using the two-digit FIPS code and the Post Office abbreviation for the state (ex. 02_AK for Alaska). Within the state subdirectory each county file has the name TGRssccc.ZIP, where the "ss" is the state FIPS code and "ccc" is the county FIPS code.
The data for each county is stored in this single compressed file that when decompressed results in up to 17 separate files representing each of the TIGER/Line record types that exist for that county. Some counties did not require all of the 17 record types and therefore will have less than 17 files. If the types of data contained in record types 4, 6, 7, 8, 9 and Z are not appropriate for a given county then the files for those record types will not be included. The name of each of these files uses a modification of the above convention (TGRssccc.RTx) where "x" is the Record Type.
Appendix A of the documentation provides a list of counties and their FIPS codes by state.
Information on the content of each record type can be found in Chapter 6 of the TIGER/Line documentation. Information on decompressing the data files is found below under the heading
The files use the TIGER/Line record formats as described in the accompanying documentation. When decompressed they are fixed length ASCII with record separators (carriage return, line feed). The CD-ROM is in ISO 9660 format. Users with PCS will require Microsoft CD-ROM Extensions Version 2.0 or higher.
ADDITIONAL CONTENTS OF THE CD-ROM:COUNTSss.TXTKNOWN PROBLEMS AND ANOMALIES WITH THIS TIGER/LINE DATA SET:
Each CD-ROM contains COUNTSss.TXT files in the subdirectory directory for each state under the TIGER directory. The COUNTSss.TXT files show record type file record counts by county for all states that are included on the compact disk. Note that all counties are listed for a given state. The layout of COUNTSss.TXT is as follows:FIPS state code 16:17 FIPS county code 20:22 Creation date 25:30 Record type 33:33 Record Count 36:43README.TXT
The document that you are presently reading.
The documentation for the TIGER/Line files is contained in the TECHDOC subdirectory. The file name is TIGER97D.PDF and is provided in the PDF format which requires the ADOBE(TM) Acrobat 3.0 reader. We are including the installation software for both the Windows 3.1 (ar16e301.exe) and the Windows 95 (ar32e301.exe) versions of the reader. They are included in the TECHDOC/ACROREAD directory. Choose the appropriate software, copy it to the hard drive of your computer and run it. It will install the ADOBE Reader software on your computer. For other computer platforms visit the ADOBE Web site for the proper software (http://www.adobe.com).
To install one of these versions copy the software from the appropriate subdirectory on the CD-ROM on to a subdirectory on your hard drive (which you named ADOBE or another name). This program will install the ADOBE Acrobat reader on the hard drive of your computer. When the installation is complete you can view the TIGER/Line documentation by running the ADOBE reader and selecting the TIGER97D.PDF file from the "Open" menu.
The TIGER/Line data on this disk has been compressed into an archive file to save space and reduce the number of disks required for the data. If the files were not compressed it would require over 40 CD-ROM disks to hold the data needed to cover the entire United States. Use software compatible with PK-ZIP 1.93A or higher to decompress the data. Info-ZIP's software (Zip, Unzip and related utilities) are examples of packages that can be used. The Info-ZIP software is free and can be obtained as source code or executables from various bulletin boards and on line services software archive sites. There are versions for many computer platforms. One site from which this software can be downloaded is: http://www.cdrom.com/pub/infozip/UnZip.htmlMISSING ZIP+4 RECORDS
In the current release of the TIGER/Line 1997 files, data users may note a significant reduction in the number of ZIP+4 Add On Codes in Record Type Z (ZIP4L and ZIP4R fields) for some areas. This reduction occurs as a result of operations to update the TIGER data base in preparation for Census 2000. These operations may replace address ranges or change the 5-digit ZIP Code, but do not automatically update or transfer the ZIP+4 codes to the new ranges. Because the Add On codes are valid for specific 5-digit ZIP Codes and address ranges, the previous Add On codes may no longer apply to the new address ranges. After these TIGER/Line files were produced we discovered that some ZIP+4 Add On Codes may be incomplete and thus erroneous.
In nearly all situations, an automated match between the Census TIGER data base and the USPS ZIP+4 file is the source of ZIP+4 Add On Codes in TIGER products. With update operations for Census 2000 underway for large portions of the nation, we have not yet performed this automated match to refresh these codes. Future releases of TIGER/Line will contain refreshed codes that will reflect a more current USPS ZIP+4 file for the address range improvements that we are now making.
ADDRESS ANOMALIES IN PUERTO RICO AND QUEENS, N.Y.
The TIGER/Line files contain some address range coverage for Puerto Rico. However, use of this information for geocoding purposes may be problematic and the data user should proceed with caution. These address ranges are preliminary attempts at using Puerto Rico address ranges in Census Bureau files. Due to the lack of software or resources to handle some of the more unique aspects of addressing in Puerto Rico, the address ranges were entered without the standard edits and quality checks used in other parts of the United States. Improvements in software and address standardization for Puerto Rico are expected in the future. At present, there are inconsistencies, overlaps, and duplication of address ranges. Address ranges may lack alpha character prefixes or have hyphenated prefixes. The files also lack the community names used in a four-line address that the U.S. Postal Service requires to avoid duplicate addresses. Errors in the reference files, and other factors may limit the usefulness of this product for geocoding purposes.
Address range data for Queens County, NY in TIGER/Line does not show a consistent use of hyphenated and non-hyphenated addressing. The Census Bureau intends to correct this in future versions of TIGER products.
ROAD FEATURE ANOMALIES
The Census Bureau extracts TIGER/Line files from the TIGER data base which is continually updated. During the update process for some 1997 TIGER/Line files errors caused anomalies to be introduced into some chains represented in Record Types 1 and 2. For these cases road features may appear in the 1997 TIGER/Line files unconnected to other road features (so-called floating features) or severely skewed in relation to surrounding line features of any type. This problem was not discovered during the normal Census Bureau correction operations. The Census Bureau will fix these disconnected or skewed features before the release of future versions of TIGER products.
The following county files have the greatest likelihood of road feature anomalies:FIPSCODE COUNTY NAME, STATE FIPSCODE COUNTY NAME, STATE 01073 Jefferson, AL 04013 Maricopa, AZ 06071 San Bernardino, CA 06073 San Diego, CA 08069 Larimer, CO 13089 DeKalb, GA 13121 Fulton, GA 13135 Gwinnett, GA 17077 Jackson, IL 18097 Marion, IN 21001 Adair, KY 21011 Bath, KY 21065 Estill, KY 21067 Fayette, KY 21095 Harlan, KY 21109 Jackson, KY 21131 Leslie, KY 21165 Menifee, KY 21175 Morgan, KY 21189 Owsley, KY 21203 Rockcastle, KY 22017 Caddo, LA 24003 Anne Arundel, MD 24035 Queen Anne's, MD 26093 Livingston, MI 26115 Monroe, MI 26125 Oakland, MI 26147 St. Clair, MI 26161 Washtenaw, MI 26163 Wayne, MI 34003 Bergen, NJ 36029 Erie, NY 36055 Monroe, NY 37119 Mecklenburg, NC 42003 Allegheny, PA 42007 Beaver, PA 42019 Butler, PA 42071 Lancaster, PA 42125 Washington, PA 42129 Westmoreland, PA 45031 Darlington, SC 45057 Lancaster, SC 45071 Newberry, SC 46099 Minnehaha, SD 47037 Davidson, TN 48229 Hudspeth, TX 48453 Travis, TX 50003 Bennington, VT 50007 Essex, VT 50015 Lamoille, VT 50021 Rutland, VT 55025 Dane, WI
VERSION NUMBER CHANGE
This release of the 1997 TIGER/Line reflects corrections to data errors discovered in the earlier releases of the 1997 product. In the process of correcting these errors we made an unrelated change to the VERSION number. The VERSION NUMBER found in this release (September 1998) of TIGER/Line reflects the vintage date of the internal TIGER data base from which the TIGER/Line file was extracted. That is the date (month/year) that the internal TIGER data base was used for a given county (or equivalent). This represents a change from the earlier 1997 TIGER/Line files that were released (prior to September 1998). Those earlier files had a VERSION number that represented the month/year that the TIGER/Line file for that county was created. This date could have been several months later than the vintage of the internal TIGER data base so we felt that using it was not as indicative of the true vintage of the data as the approach that we are using for this version (and subsequent versions).
This change is of interest principally to those who may have copies of the earlier release TIGER/Line files. The reason being that this change will, in many cases, result in the most current and correct version of the 1997 TIGER/Line files having an earlier VERSION number than the files it supplants. If in doubt on which is the most current release, one can refer to the date of the COUNTSss.TXT file accompanying TIGER/Line files on the CD-ROM as correct in relationship to the relative currency of the release. The date in the COUNTSss.TXT file reflects the processing date for the production of the TIGER/Line file.
NAMING STANDARDS IN RECORD TYPE 1
The Census Bureau changed its naming standards in Record Type 1 affecting the data in the Feature Direction, Prefix (FEDIRP), Feature Name (FENAME), Feature Type (FETYPE), and Feature Direction, Suffix (FEDIRS) fields. In previous TIGER/Line products, directional prefixes and suffixes could appear for any type of line feature. For the TIGER/Line 1997, only road features, those features with a Census Feature Class Code (CFCC) in the A class, should have feature directional data in the directional fields. Other types of chains representing other types of features (for example, hydrologic features in CFCC class H) no longer are standardized to show directional information.
The Census Bureau also modified the extraction of feature directional, name, and type information to improve the standardization of road feature information. The improvement parses a greater number of road chains into the correct feature identifier fields.
QUESTIONS AND ADDITIONAL INFORMATION
Technical questions about the Census TIGER/Line files and future plans for this and other TIGER-related products may be directed to the Products and Services Staff of the Geography Division at (301) 457-1128 or to the e-mailaddress email@example.com. In addition to this Cooperative Program version of TIGER/Line the Census Bureau also produces a version of TIGER/Line for public sale and a variety of related products based on TIGER data. General information about these products is available from the TIGER page on the Census Bureau's World Wide Web site (http://www.census.gov/geo/www/tiger/). This Web site also is a source of information that is of specific interest to TIGER/Line users and of general interest regarding the geographic programs at the Census Bureau.
Listed below are a variety of such information that typically appear on the site: As appropriate, additional information about this product will be posted, such as ERRATA or USER NOTES.
There is a TIGER Special Interest Group (SIG) which meets at various professional conferences in an informal setting to discuss issues relating to the use of TIGER/Line and future developments. Announcements telling the location of upcoming TIGER SIG meetings is posted on the TIGER Web page. There also is a list of vendors that provide services or products related to TIGER/Line.
The Census Bureau has published a Geographic Areas Reference Manual (GARM) which is available on the Census Bureau's Web site (http://www.census.gov/geo/www/garm.html). This publication describes the various geographic programs at the Census Bureau and provides definitions of technical terms and a wealth of background information on the various geographic concepts used by the Census Bureau. The manual was produced in ADOBE PDF format and is separated into individual chapters to provide smaller file sizes for easier access. Windows is a trademark of the Microsoft Corporation. ADOBE and Acrobat Reader are trademarks of Adobe Systems Inc.
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