File Geodatabase Feature Class
Tags
transportation, Texas, Linear Feature, Address Range, Street Centerline, Road Feature, Roads
This layer contains primary and secondary roads in Texas. This line file was specifically designed for medium scale thematic mapping and analysis.
The spatial data
originated
from
the US Census Bureau and were processed further by the Texas Tech Center for Geospatial Technology. Geoprocessing was performed to connect all road features and delete extraneous features.
The attributes were modified to include name, type,
code information
, identification
information.
"Primary roads are generally divided, limited-access highways within the interstate highway system or under State management, and are distinguished by the presence of interchanges. These highways are accessible by ramps and may include some toll highways. The MAF/TIGER Feature Classification Code (MTFCC) is S1100 for primary roads. Secondary roads are main arteries, usually in the U.S. Highway, State Highway, and/or County Highway system. These roads have one or more lanes of traffic in each direction, may or may not be divided, and usually have at-grade intersections with many other roads and driveways. They usually have both a local name and a route number. The MAF/TIGER Feature Classification Code (MTFCC) is S1200 for secondary roads." - US Census Bureau
Center for Geospatial Technology, Texas Tech University US Census Bureau
The TIGER/Line Shapefile products are not copyrighted however TIGER/Line and Census TIGER are registered trademarks of the U.S. Census Bureau. These products are free to use in a product or publication, however acknowledgement must be given to the U.S. Census Bureau as the source. The horizontal spatial accuracy information present in these files is provided for the purposes of statistical analysis and census operations only. No warranty, expressed or implied is made with regard to the accuracy of the spatial accuracy, and no liability is assumed by the U.S. Government in general or the U.S. Census Bureau, specifically as to the spatial or attribute accuracy of the data. The TIGER/Line Shapefiles may not be suitable for high-precision measurement applications such as engineering problems, property transfers, or other uses that might require highly accurate measurements of the earth's surface.Coordinates in the TIGER/Line shapefiles have six implied decimal places, but the positional accuracy of these coordinates is not as great as the six decimal places suggest.
Extent
| West | -106.628579 | East | -93.519429 |
| North | 36.500700 | South | 25.892126 |
| Maximum (zoomed in) | 1:5,000 |
| Minimum (zoomed out) | 1:150,000,000 |
Center for Geospatial Technology, Texas Tech University US Census Bureau
The TIGER/Line Shapefile products are not copyrighted however TIGER/Line and Census TIGER are registered trademarks of the U.S. Census Bureau. These products are free to use in a product or publication, however acknowledgement must be given to the U.S. Census Bureau as the source. The horizontal spatial accuracy information present in these files is provided for the purposes of statistical analysis and census operations only. No warranty, expressed or implied is made with regard to the accuracy of the spatial accuracy, and no liability is assumed by the U.S. Government in general or the U.S. Census Bureau, specifically as to the spatial or attribute accuracy of the data. The TIGER/Line Shapefiles may not be suitable for high-precision measurement applications such as engineering problems, property transfers, or other uses that might require highly accurate measurements of the earth's surface.Coordinates in the TIGER/Line shapefiles have six implied decimal places, but the positional accuracy of these coordinates is not as great as the six decimal places suggest.
Primary and Secondary Roads State-based
U.S. Census Bureau
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Feature geometry.
Esri
Coordinates defining the features.
Current state Federal Information Processing Standards (FIPS)
code
U.S. Census Bureau
Linear feature identifier
U.S. Census Bureau
data are unavailable
Concatenation of expanded text for prefix qualifier, prefix
direction, prefix type, base name, suffix type, suffix
direction, and suffix qualifier (as available) with a space
between each expanded text field
U.S. Census Bureau
data are unavailable
Route type code
U.S. Census Bureau
MAF/TIGER feature class code
U.S. Census Bureau
Length of feature in internal units.
Esri
Positive real numbers that are automatically generated.
The spatial data originated from the US Census Bureau and were processed further by the Texas Tech Center for Geospatial Technology. Geoprocessing was performed to connect all road features and delete extraneous features. The attributes were modified to include name, type, code information, identification information."Primary roads are generally divided, limited-access highways within the interstate highway system or under State management, and are distinguished by the presence of interchanges. These highways are accessible by ramps and may include some toll highways. The MAF/TIGER Feature Classification Code (MTFCC) is S1100 for primary roads. Secondary roads are main arteries, usually in the U.S. Highway, State Highway, and/or County Highway system. These roads have one or more lanes of traffic in each direction, may or may not be divided, and usually have at-grade intersections with many other roads and driveways. They usually have both a local name and a route number. The MAF/TIGER Feature Classification Code (MTFCC) is S1200 for secondary roads." - US Census Bureau
This layer contains primary and secondary roads in Texas. This line file was specifically designed for medium scale thematic mapping and analysis.
Publication Date
None
The TIGER/Line Shapefile products are not copyrighted however TIGER/Line and Census TIGER are registered trademarks of the U.S. Census Bureau. These products are free to use in a product or publication, however acknowledgement must be given to the U.S. Census Bureau as the source.
The horizontal spatial accuracy information present in these files is provided for the purposes of statistical analysis and census operations only. No warranty, expressed or implied is made with regard to the accuracy of the spatial accuracy, and no liability is assumed by the U.S. Government in general or the U.S. Census Bureau, specifically as to the spatial or attribute accuracy of the data. The TIGER/Line Shapefiles may not be suitable for high-precision measurement applications such as engineering problems, property transfers, or other uses that might require highly accurate measurements of the earth's surface.Coordinates in the TIGER/Line shapefiles have six implied decimal places, but the positional accuracy of these coordinates is not as great as the six decimal places suggest.
Accurate against Federal Information Processing Standards (FIPS), FIPS Publication 6-4, and FIPS-55 at the 100% level for the codes and base names. The remaining attribute information has been examined but has not been fully tested for accuracy.
There may be some inconsistencies in feature names along features. An anomaly exists with the sporadic occurrence of road segments comprising a complete chain with different MAF/TIGER Feature Census Class Code (MTFCC) values assigned. This problem could affect applications that use the MTFCC values for network analysis, routing, or for assigning symbology to a feature when creating a map.
The Census Bureau performed automated tests to ensure logical consistency and limits of shapefiles. Node/geometry and topology relationships are collected or generated to satisfy topological edit requirements. These requirements include:
(1) Complete chains must begin and end at nodes.
(2) Complete chains must connect to each other at nodes.
(3) Complete chains do not extend through nodes.
(4) Left and right polygons are defined for each complete chain element and are consistent throughout the extract process.
(5) The chains representing the limits of the files are free of gaps.
Data completeness of the TIGER/Line Shapefiles reflects the contents of the Census MAF/TIGER database at the time the TIGER/Line Shapefiles were created.
The Census Bureau uses Global Positioning System (GPS) coordinates at road centerline intersections to evaluate the horizontal spatial accuracy of source files that may be used to realign road features in the MAF/TIGER database and test the horizontal spatial accuracy of the road features in the TIGER/Line Shapefiles. The test compares a survey-grade GPS coordinate to its associated road centerline intersection in the TIGER/Line Shapefiles. The test is based on an independent collection of GPS coordinates for a random sample of road intersections from a centerline file that meet certain criteria. The points are referred to as the sample points and are gathered through a private contractor working for the Census Bureau. Since the collection method uses survey-quality GPS-based field techniques, the resulting control points are considered 'ground truth' against which the TIGER road centerline intersection coordinates are compared. The distances between the coordinates are calculated and the Census Bureau determines the Circular Error 95% (CE95). That is, the accuracy of the file in meters with 95% confidence. The CE95 can be calculated from the mean and standard deviation by using the formula: mean of differences plus (2.65 times the standard deviation). CE95 results reported for each file tested are determined using a spreadsheet with embedded statistical formula. The use and applicability of the spreadsheet and its embedded formula have been verified by Census Bureau statisticians. The basis of the calculation is the use of the root mean square error (RMSE). This is the method as stated in the U.S. Government's Federal Geographic Data Committee Standard FGDC-STD-007.3-1998, Geospatial Positioning Accuracy Standards. Part 3: National Standard for Spatial Data Accuracy. The results of using this measure of accuracy are in compliance with Federal Spatial Data requirements. In terms of the Census Bureau application, the dataset coordinate values are those taken from the centerline file and the coordinate values from an independent source of higher accuracy are those acquired through the Census Bureau's contractor. Please note that the horizontal spatial accuracy, where reported, refers only to the realigned road features identified as matched to the positionally accurate source file with that accuracy. It is not the spatial accuracy of the TIGER/Line Shapefile as a whole.
The selected geographic and cartographic information (line segments) are derived from the U.S. Census Bureau's Master Address File Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER) database.
TIGER/Line Shapefiles are extracted from the Census MAF/TIGER database by nation, state, county, and entity. Census MAF/TIGER data for all of the aforementioned geographic entities are then distributed among the shapefiles each containing attributes for line, polygon, or landmark geographic data.
No warranty, expressed or implied is made with regard to the accuracy of these data, and no liability is assumed by the U.S. Government in general or the U.S. Census Bureau in specific as to the spatial or attribute accuracy of the data. The act of distribution shall not constitute any such warranty and no responsibility is assumed by the U.S. government in the use of these files. The boundary information in the TIGER/Line Shapefiles is for statistical data collection and tabulation purposes only; their depiction and designation for statistical purposes do not constitute a determination of jurisdictional authority or rights of ownership or entitlement and they are not legal land descriptions.
To obtain more information about ordering TIGER/Line shapefiles visit http://www.census.gov/geo/www/tiger