Prepared by
Forrest M. Council
Carolyn Williams
University of North Carolina
Highway Safety Research Center
730 Martin Luther King Jr Blvd, Suite 300
Chapel Hill, NC 27599-3430
and
Li wan Chen
Yusuf M. Mohamedshah
LENDIS Corporation
Turner-Fairbank Highway Research Center
Federal Highway Administration
6300 Georgetown Pike
McLean, VA 22101
Prepared for
Federal Highway Administration
Office of Safety and Traffic
Operations Research & Development
U.S. Department of Transportation
Washington, DC 20590
December, 1999
(NOTE: Changes from the previous edition of the Guidebook are shown in bold and italic.)
Maine's basic TINIS (Transportation Integrated Network Information System) brings together information data concerning accidents, road inventory, bridges, railroads, and project history/maintenance type information. Unlike other HSIS states in which the linkage variable is some form of route-milepoint, the Maine system is a county/link-node system in which a six-digit code defines a specific node (e.g. an intersection, bridge, or other boundary) in a specific county. Each roadway section, or "link," is then defined by the node numbers at each end. The single raw file which will be received from Maine each year for use in the HSIS will include the following records:
HSRC programmers divided this single raw file into subfiles containing each of the above types of records. Copies of these smaller files and copies of the documentation (variable listings, definitions, etc.) for these files has been provided to FHWA.
The Maine format for single crashes is then reformatted by HSIS programmers into the standard HSIS format B Accident, Vehicle, and Occupant subfiles. For additional consistency, variables related to drivers have been included both on the Occupant subfile and the Vehicle subfile.
Raw file data is provided to the Highway Safety Research Center where they are retained as backup information. The documentation (variable listings, definitions, etc.) for these raw files and for the SAS files that are developed from them are available at FHWA offices. Conversion programs developed by HSRC and LENDIS to convert the files into SQL and SAS formats are also available at the HSIS offices at FHWA.
Beginning in 1994, the HSIS system was converted to a relational database for internal use. This database, using a SYBASE system, stores the data received from Maine and other states, and the data files for a given state are linked and manipulated using SQL language. However, this conversion from the original SAS-based system to the newer relational system is somewhat transparent to the end-user of the data since the output files produced by SYBASE for modeling and analysis will be SAS formatted. As in the past, we have continued to produce SAS format libraries for each of the variables in each of the files. Because it is envisioned that the majority of analyses will utilize these SAS files and formats, this Guidebook will concern these SAS files -- their formats, completeness, and quality. While single-variable tables for key variables from each file were published in the past as “Volume II”, this is no longer the case. Users may request specific single- or multiple-variable tables through the HSIS “Data Request” procedure found on this web site.
As noted above, the accident data is in three separate files. The Accident subfile, containing basic information on accident type, location, environment, etc., can be linked with the Vehicle subfile (which contains information on each vehicle and each driver in the crash) and the Occupant subfile (which contains information on each occupant in each vehicle).
The Link Records File contains characteristics of approximately 23,000 miles of public road in Maine. This includes all public highways in the State, both rural roads and urban streets. Approximately 85 percent are rural in nature. (Note that this is different from other HSIS state files, where the Astate system@ of roadways do not include all public highways.)This file contains roadway characteristics including shoulder and median information, pavement type and width, lane information, etc. It is noted that in order to cover situations in which a roadway characteristic changed within a link, this raw file contains information on up to five possible changes for most variables within the link, and up to five "Distance From" variables which indicate the distance from the lower order node to the change. For ease of use, this file has been reformatted such that a record contains a "homogeneous" section (sublink) of roadway. This reformatted Link Records File also contains traffic information (AADT) for the link. This will eliminate the amount of merging that will have to be done by future users.
The Node Records File contains the six-digit node number (a two-digit county code and a four-digit code unique within a county) and limited information on the characteristics of approximately 56,000 junctions, bridges and/or other boundaries across the state. The file contains information related to the intersection configuration, number of legs, and linkage information concerning surrounding nodes. It also contains information concerning "Millions of Entering Vehicles" and the presence of signalization if the node is an intersection. As a supplement to this file, an Interchange File has been developed which includes information on all interchanges on Maine Interstates -- location, type, etc.
The Railroad Grade Crossing File is a file containing information on all grade-crossings in the State, and is prepared and maintained according to FHWA requirements. As is the case with most States, the Bridge File contains information on bridge structures across the State. The data is considered quite accurate since it is based on the federal bridge inventory.
Due to established priorities of effort, HSRC staff did not work with the Railroad Grade-Crossing File or the Bridge File. Thus, these files were not converted into SAS files. Details of the three Accident subfiles, the Link Records File, and the Node Records File are presented in the following section.
The Maine accident data is collected by state police, local police and county sheriffs on a uniform accident report form. An accident was reported prior to 1999 if it involved $500 total damage/or personal injury. The dollar value changed from $500 to $1000 as of 9/18/1999. All crash reports are sent to the State Police who code and punch the data. Annual data tapes and hard copies are forwarded to the Bureau of Planning within the Maine DOT for further preparation before being entered in the TINIS system. Here, coders use the accident report forms to extract location information and to check and recode, if necessary, key items involving the "Accident Type," "Location Code" and "Fixed Object Struck." The items recoded are the primary items used by Maine in their high accident location analysis and in the development of accident diagrams. The consensus is that the state police data are of better quality than the local data, but the local data appears to be quite adequate for the uses made of it.
Currently there are thirteen years of accident data in the Maine HSIS files - 1985-1997. The data set includes approximately 39,000 accidents per year, 66,000 vehicles per year, and 94,000 occupant/pedestrians per year. As noted earlier, the occupant subfile contains information on each occupant in the crash whether injured or not, including the drivers. The driver information is also placed on the Vehicle subfile. It is also noted that the number of accidents, vehicles and occupants in the three files has decreased from 1990 to 1994 , and then increased through the later years. Maine staff have had indicated that this represented actual decreases in statewide reportable accidents (rather than problems with the data), and could well result from changes in the State's economy in 1990-1994. Unfortunately, there is no "Urban-Rural" variable in the accident data, and the "Investigating Agency" code does not distinguish between rural and urban crash investigations. Thus, there is no way to define the "ruralness" of the data (without linkage with the Link/Node files). However, given the large proportion of roads that are rural, it would be expected that Maine accidents are more rural than the accidents of other HSIS States.
Various single variable tabulations were run to look at the question of reporting completeness and accuracy among the accident variables. Here, we studied the percent of unknown or uncoded values for 23 key variables from the Accident subfile, 11 from the Vehicle subfile, and 3 from the Occupant subfile. These variables ranged from various accident descriptors including accident type, day of week, number of vehicles involved, accident severity, road surface, object struck, and investigating agency; to vehicle-related variables involving vehicle type, contributing factors, and driver information; to occupant variables related to age, sex and injury severity.
The quality control checks indicated that the overwhelming majority of the variables on the Accident subfiles appeared to be quite completely coded and quite accurate. There were virtually no cases in which the number of uncoded variables was greater than two percent, and most were uncoded in less than one percent of the cases.
With respect to the accuracy of the data, comparisons were made of pairs of variables in the file which should have been somewhat similar according to their definitions. In addition, the single-variable distributions were compared to the other HSIS States to see if large differences existed.
As with the case of completeness, these checks indicated that, in general, the Maine data are quite accurate. For example, the number of cases in which there is a second vehicle noted in the variable related to "Number of Vehicles" matches quite well with the proportion of accidents which would be considered multi-vehicle in the "Accident Type" variable. The distribution in "Weather" matched well with the distribution of "Road Condition." In similar fashion, the distributions for "Driver Condition" and "Severity" were as would be expected from the data of other States.
There were a few variables whose distributions raised some questions, either in terms of changes across time or "shape" of the distribution itself. For example, certain categories in the variables related to "Accident Type" and "Location Code" appear to change rather dramatically between the 1985-86 period and the 1987-97 period. At approximately the beginning of 1987, Maine staff began to recode the data in-house for their use. This means that there will be a few categories within these two variables which will change due to coding across the time period. However, the changes do not affect other variables, and do not appear to greatly affect many categories within these two variables. The data for all the files after 1987 are consistent.
The Accident subfile variable related to "Non-Intersection" should not be used as an indicator of intersection crashes, and analysis and conversations with Maine staff indicated that 1985 accident data should not be used when performing intersection accident analyses. Instead of "Non-Intersection", the variable LOC_TYPE on the accident file should be used to define intersection-related crashes. (To be more conservative, one might require agreement between the LOC_TYPE variable on the Accident Subfile and the TYPEDESC variable on the Node File, after the interchange-related nodes are removed.)
Finally, it is noted that the definitions of categories within the variable related to "Vehicle Type" changed significantly in the 1989 data. This has resulted in significant changes in the number and percent of various truck types involved in crashes over the years (see Vehicle Type table in later section). More specifically, Maine has gone to a much more detailed set of codes related to truck type, changing from general codes related to "tractor trailer" and "tractor semi-trailer" to new codes as specific as "2-axle semi plus 3-axle trailer". Thus, the number of cases found in the earlier non-specific categories drops dramatically in the 1988 and 1989 data. Care will have to be taken in grouping these truck codes in future analyses.
For these and other variables which either have higher proportions of uncoded data or for which an accuracy issue has been raised by analysis efforts, a "NOTE" has been included under the variable in the later Format section of this Guidebook.
In summary, analysis of the Maine Accident, Vehicle, and Occupant subfiles indicated that these files are quite accurate in almost all cases, are quite internally consistent, and, with few exceptions, have very few uncoded cases.
This file contains information on approximately 23,000 miles of public roads in Maine, and covers all public highways and streets in the State. Thus, in contrast to most other HSIS States which include only higher order routes, the Maine system covers all the mileage within the State. The table below provides a categorization of the mileage by certain roadway classes. Unpaved mileage is not included in this table, but will be in the full file.
| Roadway Category | Mileage |
|---|---|
| Urban Freeways | 121.81 |
| Urban Freeways < 4 ln | 26.00 |
| Urban multilane divided non freeways | 16.34 |
| Urban multilane undivided non freeways | 56.88 |
| Urban 2 lane roads | 2422.76 |
| Rural Freeways | 592.75 |
| Rural Freeways < 4 ln | 22.73 |
| Rural multilane divided non freeways | 2.49 |
| Rural multilane undivided non freeways | 21.81 |
| Rural 2 lane roads | 16824.94 |
| Others | 3067.50 |
| Total | 23176.01 |
Data on the file are updated by the Inventory Section of the Maine Bureau of Planning. The inventory information is felt to be quite accurate (perhaps with the exception of the variable related to median barriers). The data were originally updated by a two-person team who continually inventoried everything on public highways (even roads not under State control). They forwarded necessary changes to the Bureau for updating. This road inventory team covered the entire state on a five-year cycle. Due to budget restrictions of the early 90's, inventory changes are now pulled from a continual review of construction and maintenance plans by internal rural planning staff and review of video logs, and everything that changes one of the inventory items is changed in the TINIS system as soon as the change is forwarded to the central office, almost always within a year of the change. In urban areas, the division engineering staff does inventory checks on a four-year cycle.
As noted above, the raw Link file has been reformatted such that the SAS Link Records File contains "homogeneous" (sub)links of roadway. That is, in the original file, many of the variables could have up to five changes within a given link, and a distance to each change was recorded. In the SAS file, any time any variable changes within a link, a new link begins. In terms of use, this makes this SAS file more nearly resemble the "route/milepost" files found in the other HSIS States. It is noted that, in some links, problems were found during the development of sublinks (e.g., a change in a variable was noted at a distance greater than the length of the link or two changes in the same variable "overlapped"). While these problems only occurred in a small percentage of the links, they could not be corrected. To identify these problem links, a "Distance Problem Flag" variable was added to each record in the file. For analysis and merging purposes, only those records where PROBLEMS is coded "0" should be used.
This Link file contains information on approximately 83,000 records within the state covering the 23,000 miles of total system roadway. It is noted that two separate links exist for each section of the approximately two percent of the roadway that is divided -- one link for each direction. This means that computer runs which accumulate mileage for all links will produce inflated mileage totals due to double-counting mileage for these sections. Approximately 61 percent of the mileage are local roadways, 26 percent of the mileage are collector routes, and the remaining 14 percent of the records concern Interstates, other principal arterials, and minor arterials. While 50 percent of the records are rural in nature, these represent approximately 85 percent of the total mileage in the system, with the remaining being roads in mixed areas or municipalities. As expected from the rural nature of the state, the majority of roadways carry relatively low volumes of traffic, with AADT's of 500 vehicles per day or less. The average length of a link in the rural areas is approximately 0.5 miles, and is 0.1 miles in the urban areas.
In terms of completeness of the data, most of the variables on the file are coded very completely with very few missing values. While there are a limited number of variables with large percentages of uncoded ("blank") data, these are generally "default" values which imply the opposite code (e.g., a "blank" in the variable related to "55/65 Posted Speed Limit" indicates that a lower speed limit exists; a "blank" in "HPMS Section" indicates a non-HPMS section).
Two new variables, RODWYCLS and MVMT, have been created by HSIS staff in the roadway segment file of each of the HSIS states. For Maine, they are included in this Links File. The RODWYCLS (Roadway Class) variable is based on the combination of rural/urban, access control, number of lanes and median type variables. This variable classifies each roadway segment into one of ten roadway types described in the later AFormat@ section. This variable is also included as a accident-file variable by matching each crash to its corresponding roadway segment. The MVMT variable (Million Vehicle Miles of Travel) is calculated for each segment in the roadway file by multiplying the segment length, AADT and 365 days in a year, and dividing by one million. Both these variables were created in response to inquires from data users, whose most frequent questions have concerned either crash frequencies or rates (per MVMT) for one or more of these roadway classes.
With respect to accuracy of the data, in general, the variables on the Link File are also coded quite accurately. Comparisons of similar variables appear to give very consistent results, and the distributions are similar to what would be expected from other States. For example, the variables related to "Right Shoulder Type" and "Left Shoulder Type" both matched quite well with each other and with the respective variables concerning "Shoulder Width." The variable related to "Municipality" matched well with the "Urban-Rural Code." And, in general, the distributions were as expected.
With respect to traffic volumes, variables related to "factored AADT" are more accurate than variables related to "AADT" (including the "year" variables), according to the Maine staff. The information in the "factored" variables reflects the true traffic counting procedures and results. The non-factored variables contain some misleading information due to lack of accurate "update year" information for sections of local roads on the system, and other problems. As stated in the "Notes" in the SAS Formats, the "factored" variables should be used in all analyses.
Thus, in general, the variables on the Link file are quite accurate and very suitable for analysis efforts. Issues raised in subsequent analyses are included as a "NOTE" under the pertinent variable in the later format section.
The Nodes File contains information on approximately 56,000 points on the roadway system which are used to define the ends of links. In over 96 percent of the cases, these points are either intersections, railroad crossings, bridges, ends of roads or routes, or State, county or town boundaries. In 2.1 percent of the cases, the node is a "dummy" node interjected into a route to limit the maximum length of a link to six miles. Approximately 63 percent of nodes are intersections of roadways, 17.3 percent are ends of roads, and 2.5 percent are bridges. The remainder are either railroad grade crossing, boundaries, or "dummy" nodes.
In terms of the completeness of the data, the quality control runs indicated that the variables are coded quite accurately. There are a few cases, however, where discussions with Maine staff indicated that the data is not accurately coded. These include variables related to "Number of Approaches," "Traffic Signal," and "Traffic Signal Indication." Again, a "NOTE" has been included under the variable in the later format section of the Guidebook which explains the problem or issue.
With respect to accuracy, while there are very few pairs of variables which measure similar attributes, the distributions of variables appear to show that the data is quite accurate. This accuracy is also supported by the amount of effort that Maine staff puts into inventorying the Statewide roadway system on a regular basis and in updating the data files. However, there are some points that should be noted in use of the Node file in intersection analyses.
Because of the nature of the node records (i.e., approximately 64 percent of the nodes represent intersections of roadways), the node file can in some senses be used as an "intersection" file in that it contains information on the geometric configuration of the intersection, the number of legs, and the number of annual entering vehicles. However, preliminary work with this file has indicated the following "warnings" for such future analyses.
First, while the variable related to "Geometric Configuration" (TYPEDESC) specifies the various types of intersections that can occur at a node (e.g., cross--90 degree, cross--skewed, tee, etc.), there is no indication within this variable (or the entire file) that can be used to separate at-grade intersections from interchanges. This is due to the basic definition of a roadway-related node -- a point where two roads cross, converge, or diverge. Thus, for example, for a divided highway, each ramp entrance or exit on each side of the roadway will usually (but not always) be coded as a separate node (with the "Configuration" being "wye" or perhaps "tee"). However, there is no way of determining from the existing Node file which "Wye" intersections are "true" intersections of roadways, and which are ramps. If one is attempting to isolate non-ramp intersections, there is a variable on the Link file which indicates whether a road section is a ramp or not (i.e., "Ramp"). If all "wye" and "tee" nodes are merged with all incoming links, a check can be made to determine which nodes are "true" non-ramp locations.
However, a second (better) solution now results from the creation of a Maine Interchange File. As discussed in the following section, this file was created since there is no simple (programming) method to identify interchanges using the Node File. Each side of the divided roadway may have from two to four interchange-related nodes within varying distances of each other, in addition to all the nodes related to ramp ends on the crossing road. While the File itself will be described in detail below, it is now possible to identify all "true" intersections by the following method. First, identify all "intersection" nodes from the Node File. Second, match these intersection nodes (using the "County Key" and "Node Number") with the total listing of nodes in the Interchange File. (See detailed instruction for matching under variable I_NE01 in the Interchange File.) After eliminating all matches, any nodes remaining can be considered "true" at-grade intersections not related to interchanges. However, as discussed above, there will still be some disagreement between the "cleaned" intersection set and intersections as specified on the accident report using the LOC_TYPE variable. Again, it is recommended that the LOC_TYPE variable be the controlling variable.
Thus, with very few exceptions, the variables in the Node File are both coded a high percentage of the time and appear to be quite accurate.
With respect to the traffic information on both the Link and the Node File, the traffic counts that are in the system are extracted from a traffic file again prepared within the Traffic Engineering Division. The counts are extracted from a series of 57 permanent count stations across the State, six of which do detailed vehicle classification counts. There are a total of 11 stations on Interstate routes (which collect counts in both directions), approximately 16 stations on U.S. routes, 24 stations on State routes, and six stations on other routes.
In addition to the continuous count stations, each summer 24-hour counts were done at between 1600-2200 locations on all US and State highways prior to 1994. Beginning in 1994, the number of coverage counts increased to between 1800 and 3300. Approximately 10 percent of these counts include vehicle classification counts. Classification estimates exist for other locations that are not high priority locations.
Each year, these counts are done in either the northern, central, or southern areas of the State. The counters move to a different area the following summer, covering the entire State every five years. The southern and central areas are counted in alternate years for the first four years of a cycle. Then the northern area, where counts change less per year, is counted during the fifth year of the cycle. Seasonal adjustment factors for the coverage counts are based on continuous count stations which fall into the same "highway type" category as the coverage count. Based on extensive analysis in the late 1980's, the three categories used are Urban (including suburban locations), Arterial (including all Interstate locations plus other locations in rural areas), and Recreational locations (whether urban or rural). The actual adjustment factor for a given coverage count location is based on the weekly average ADT for all continuous count stations falling into that category.
For years in which no count data were collected within a given area of the state, historical daily traffic flows are factored up on a county by county basis. The growth factor used is based primarily on traffic changes at the continuous count stations falling into the same highway-type category described above. Other information used in developing a specific growth factor includes counts from nearby urbanized areas and special counts that may have been conducted at the location for other reasons. The final growth factor used is based on interpolation between points of known growth (such as two or more years at the similar continuous count stations), and is done by personnel with a working knowledge of the system's traffic patterns.
In summary, while some of the counts may be off due to the roadside development and/or roadway construction within a specific area of the state that occurred within the two year period, in general, the count data are felt to be quite adequate for analysis purposes.
As noted above, while the previously described Node File identifies certain locations as intersections (using the variable NODE1ST), there was no way to identify which intersection nodes were simple intersections and which were part of a more complex interchange. Because certain analyses are requiring specific identification of interchanges, the Interchange File was developed as a supplement to the Node File.
This file contains one entry per interchange, rest area, toll plaza or truck weigh station. (These non-interchange nodes can be screened from analysis runs using the variable I_TYPE.) Interchanges were located using Interstate node maps provided by the State of Maine, and each such interchange was assigned a unique number based on route and sequence. (Discussions with Maine staff indicated that all interchanges are located on Interstate routes.) Each entry includes descriptive information (such as unique identification number, county, interstate route number, descriptive name, exit number), the type of interchange, the presence of a toll facility at the interchange, the number of nodes, and a list of all node numbers for that location. A maximum of twenty eight nodes are possible (allowing for fourteen nodes on the northbound or eastbound direction and fourteen nodes on the southbound or westbound direction). These numbers for each node are as provided by Maine staff, and thus the order has no significance.
In addition, no attempt was made to define the component parts of the interchange. Therefore, there is no code to distinguish main-line interstate nodes, ramp terminators, ramp intersections, bridges, toll booths, etc. However, there is a "Ramp" variable on the Link File which indicates whether a specific link (between two nodes) is a ramp. This variable could be used in cases where the identification of ramps is of interest.
The accuracy of the development of this file was checked by generating a report after data entry and comparing the values to the original coding forms. To reduce error, a single coder was primarily responsible for locating the extent of each interchange, copying the node numbers to the coding form and entering the raw data onto a microcomputer. The more difficult locations were discussed with a database administrator and a highway engineer.
At this time, no attempt has been made to combine this database with either the Node File or the Link File, and there are no common variables which can be compared. It is noted that there are two important considerations for combining Maine files. First, nodes are only unique within a single county, meaning that the "County Key" is an essential element of any attempt at linkage. Second, link designations always list the lower numbered node first. (See detailed instruction for matching under variable I_NE01 in the Interchange File.)
As noted above, the accident data are subdivided into three subfiles -- accident, vehicle and occupant. These subfiles can be linked together using the "case number" variable (i.e., CASENO) present in each of the three files. When linking the occupant subfile, the additional linking variable "vehicle number" (i.e., VEHNO) must match so that the occupants are associated with the vehicle in which they were traveling. To link the Vehicle subfile with the Accident alone, first sort both subfiles by case number. To link the Occupant file with the other two subfiles, first sort both the Vehicle subfile and Occupant subfile by case number and vehicle position number. Next sort the Accident subfile by case number. Alternatively, the separate subfiles can be linked by specifying an SQL JOIN operation with the constraining condition that case number and vehicle number from each table are equal. SQL processing does not require the data to be presorted and the output will not be in any particular sort order unless ORDER BY is specified.
To link the Accident Subfile with the Node File (to capture accidents occurring only at the node), one needs to select accidents in which C_HNODE = '0000'. Then sort both the Accident and Node Files on B_LINK, and link with this variable.
The Accident Subfile can then be linked with the Link File using the appropriate county/link-node numbers and the appropriate distance from the low node. The latter is necessary since a given link, as defined by a low and high node, can be divided into sublinks with different roadway characteristics. This linkage is done by first sorting the Accident Subfile by C_LINK and the Link File by A_LINK. (Both of these variables contain information on both county and node number.) The linkage is then done by requiring that these two variables be equal, and that BEGMP < MILEPOST and MILEPOST < ENDMP. Here, MILEPOST is found on the Accident Subfile and BEGMP and ENDMP are on the Link File.
Matching roadway characteristics information from the Link File with the appropriate node in the Node File is more complex, since the characteristics to be linked may fall on any of up to six incoming/outgoing links, and may fall in the first of last sublink of a given link. This linkage will require programming on the part of the user. Since this programming has been done for certain analysis tasks by the HSIS computer staff, the analyst is advised to contact the HSIS office at FHWA (202-493-3464) for assistance.
Finally, where appropriate and possible, a format which defines categories within a given variable has been developed for HSIS SAS variables. These categories are shown in the pages below. If you are a SAS user and wish to receive a formatting program which includes these SAS formats (with linkage to the pertinent variable name), please request these from the HSIS staff who provide the data file to you.
Mr. Emery is our main contact within the State of Maine when questions arise concerning the data files in general or when new data is to be generated. He works in the Information Systems Division of the Maine DOT and is responsible for the development and maintenance of the entire TINIS system. He will often be able to answer questions on the specifics of many of the files.
Mr. Costello is the contact for specific information related to accident variables. He works in the DOT Accident Records Section within Traffic Engineering and is responsible for all accident report coding and modifications to the accident subfiles.
Ms. Morgan is the contact for specific information related to traffic (AADT). She works in the DOT Traffic Section within Traffic Engineering and is responsible for the traffic counting program.
Mr. Beckwith is the TINIS Manager and should be able to answer most questions concerning information placed in TINIS. He works in the DOT Planning, Research & Community Services and is responsible for any format changes to records or files in the TINIS system.
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| A_HNODE | HIGH NODE OF LINK | Link | Char(5) | I‑52 |
| A_LINK | LINK=BOTH NODES | Link | Char(12) | I‑52 |
| A_LNODE | LOW NODE OF LINK | Link | Char(5) | I‑52 |
| AADT | ANNUAL AVGE DAILY TRAFFIC | Link | Num | I‑51 |
| AADT_TYP | AADT TYPE (EST. OR ACTUAL) | Link | Char(1) | I‑51 |
| AADT_YR | YR OF FACTORED AADT | Link | Char(4) | I‑52 |
| AADTF | FACTORED AADT | Link | Num | I‑51 |
| AADTF_YR | YEAR OF CURRENT AADT | Link | Char(4) | I‑51 |
| ACC_DATE | DATE OF ACCIDENT | Accident | Char(8) | I‑23 |
| ACCESS | ACCESS CONTROL | Link | Num | I‑52 |
| ACCTYPE | TYPE OF ACCIDENT | Accident | Num | I‑23 |
| ACCYR | YEAR OF ACCIDENT | Accident | Char(4) | I‑23 |
| AGE | OCCUPANT AGE | Occupant | Num | I‑45 |
| AGENCY | INVEST. AGENCY (?) | Accident | Char(5) | I‑23 |
| B_LINK | LINK=BOTH NODES (MOD) | Accident | Char(7) | I‑24 |
| B_LINK | KEY FOR MERGING | Node | Char(7) | I‑63 |
| B_NODE | NODE NUMBER | Node | Char(5) | I‑63 |
| BEGMP | POSITION WHERE SUBLINK BEGINS | Link | Num | I‑52 |
| C_HNODE | HIGH NODE | Accident | Char(5) | I‑24 |
| C_HNODE | HIGH NODE | Vehicle | Char(5) | I‑36 |
| C_HNODE | HIGH NODE | Occupant | Char(5) | I‑46 |
| C_LINK | LINK=BOTH NODES | Accident | Char(12) | I‑24 |
| C_LINK | LINK=BOTH NODES | Vehicle | Char(12) | I‑36 |
| C_LINK | LINK=BOTH NODES | Occupant | Char(12) | I‑46 |
| C_LNODE | LOW NODE | Accident | Char(5) | I‑24 |
| C_LNODE | LOW NODE | Vehicle | Char(5) | I‑36 |
| C_LNODE | LOW NODE | Occupant | Char(5) | I‑46 |
| CASENO | ACC CASE NUMBER | Accident | Char(9) | I‑24 |
| CASENO | ACC CASE NUMBER | Vehicle | Char(9) | I‑35 |
| CASENO | ACC CASE NUMBER | Occupant | Char(9) | I‑45 |
| CONTRIB1 | 1ST APPART CONTRIB FACTOR | Vehicle | Num | I‑35 |
| CONTRIB2 | 2ND APPART CONTRIB FACTOR | Vehicle | Num | I‑35 |
| COUNTY | MAINE COUNTY KEY | Accident | Char(2) | I‑24 |
| COUNTY | MAINE COUNTY KEY | Vehicle | Char(2) | I‑36 |
| COUNTY | MAINE COUNTY KEY | Occupant | Char(2) | I‑46 |
| COUNTY | MAINE COUNTY KEY | Link | Char(2) | I‑53 |
| COUNTY | MAINE COUNTY KEY | Node | Char(2) | I‑63 |
| DAYMTH | DAY OF MONTH | Accident | Num | I‑25 |
| DRV_AGE | DRIVER AGE | Vehicle | Num | I‑37 |
| DRV_INJ | DRIVER INJURY TYPE | Vehicle | Char(1) | I‑37 |
| DRV_SEX | DRIVER SEX | Vehicle | Num | I‑37 |
| ENDMP | POSITION WHERE SUBLINK ENDS | Link | Num | I‑53 |
| ENTVEHS | ANNUAL ENTERING VEHICLES | Node | Num (MILLIONS) | I‑63 |
(CON'T)
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| FED_AID | FEDERAL AID DESIGNATION | Link | Char(1) | I‑53 |
| FIFTY5 | POSTED 55/65 MPH ZONE | Link | Num | I‑54 |
| FUNC_CLS | FUNCTIONAL CLASS (1980 FEDERAL) | Link | Num | I‑54 |
| HOUR | HOUR OF ACC | Accident | Num | I‑25 |
| HPMS1 | HPMSSAMPLE SECTION | Link | Num | I‑54 |
| I_CNTY | COUNTY | Interchange | Char(2) | I‑71 |
| I_DESC | DESCRIPT NAME OF INTERCHANGE | Interchange | Char(30) | I‑71 |
| I_EXIT | EXIT NUMBER (optional) | Interchange | Char(2) | I‑71 |
| I_NE01 | 1st NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE02 | 2nd NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE03 | 3rd NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE04 | 4th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE05 | 5th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE06 | 6th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE07 | 7th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE08 | 8th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE09 | 9th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE10 | 10th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE11 | 11th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE12 | 12th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE13 | 13th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE14 | 14th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NECNT | NUMBER OF NODES ON NORTH/EASTBOUND SIDE | Interchange | Num | I‑73 |
| I_RTE | INTERSTATE ROUTE NUMBER | Interchange | Char(3) | I‑74 |
| I_SEQ | ASSIGNED SEQUENCE | Interchange | Char(2) | I‑74 |
| I_SW01 | 1st SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑74 |
| I_SW02 | 2nd SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑74 |
| I_SW03 | 3rd SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW04 | 4th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW05 | 5th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW06 | 6th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW07 | 7th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW08 | 8th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW09 | 9th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW10 | 10th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW11 | 11th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW12 | 12th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW13 | 13th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑76 |
| I_SW14 | 14th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑76 |
| I_SWCNT | NUMBER OF NODES ON NORTH/EASTBOUND SIDE | Interchange | Num | I‑76 |
| I_TOLL | TOLL BOOTH PRESENT? | Interchange | Char(1) | I‑76 |
(CON'T)
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| I_TOTCNT | NUM OF NODES FOR INTERCHANGE | Interchange | Num | I‑76 |
| I_TYPE | TYPE OF INTERCHANGE | Interchange | Char(4) | I‑77 |
| INJ | OCCUPANT INJURY TYPE | Occupant | Char(1) | I‑46 |
| INTCHNG | UNIQUE INTERCHANGE NUMBER | Interchange | Char(7) | I‑71 |
| INV_CNTL | ROUTE TYPE INDICATOR | Link | Char(5) | I‑54 |
| JURIS | JURISDICTION | Link | Num | I‑55 |
| LENGTH | OFFICIAL SUBLINK MILEAGE | Link | Num | I‑55 |
| LIGHT | LIGHT CONDITION | Accident | Num | I‑25 |
| LOC_TYPE | LOCATION TYPE | Accident | Num | I‑26 |
| LSHL_TYP | LEFT SHOULDER TYPE | Link | Num | I‑55 |
| LSHLDWID | LEFT SHOULDER WIDTH | Link | Num | I‑55 |
| MILEPOST | DISTANCE FROM LOW NODE | Accident | Num | I‑26 |
| MISCACT1 | PRE‑CRASH MANEUVER | Vehicle | Num | I‑38 |
| MONTH | MONTH OF ACC | Accident | Num | I‑26 |
| MVMT | MILLION VEHICLE MILES TRAVELED | Link | Num | I‑56 |
| NBR_LEGS | NUM OF INTERSECTION LEGS | Node | Num | I‑63 |
| NHS_CODE | NATIONAL HIGHWAY SYSTEM CODE | Link | Num | I‑56 |
| NO_APPR | NUMBER OF APPROACHES | Node | Num | I‑64 |
| NO_LANES | NUMBER OF LANES | Link | Char(1) | I‑56 |
| NODE_C1 | 1ST CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C2 | 2ND CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C3 | 3RD CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C4 | 4TH CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C5 | 5TH CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C6 | 6TH CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE1ST | NODE TYPE 1 | Node | Num | I‑64 |
| NODE2ND | NODE TYPE 2 | Node | Num | I‑64 |
| NONINT | NON‑INTERSECTION NODE ACC | Accident | Num | I‑26 |
| NUM_OCCS | NUM OCCUPANTS IN VEHICLE | Vehicle | Num | I‑39 |
| NUMVEHS | SINGLE OR MULTI VEH CRASH | Accident | Num | I‑27 |
| OBJECT1 | FIXED OBJECTS STRUCK | Accident | Num | I‑27 |
| ONEWAY | ONEWAY INDICATOR | Link | Num | I‑57 |
| PHYSCOND | APPARENT PHYSICAL CONDIT | Vehicle | Num | I‑39 |
| PROBLEM | DISTANCE PROBLEM FLAG (CREATED) | Link | Num | I‑57 |
| RAMP | RAMP | Link | Num | I‑57 |
| RATETYPE | RATE TYPE (LOCATION CODE) | Node | Num | I‑65 |
| RD_CHAR1 | ROAD CHARACTER | Accident | Num | I‑28 |
| RDCONSTR | ROAD CONSTRUCTION/MAINT | Accident | Num | I‑27 |
(CON'T)
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| RDSURF | SURFACE CONDITION | Accident | Num | I‑28 |
| RODWYCLS | ROADWAY CLASSIFICATION | Accident | Char(2) | I‑28 |
| RODWYCLS | ROADWAY CLASSIFICATION | Link | Char(2) | I‑57 |
| RSHL_TYP | RIGHT SHOULDER TYPE | Link | Num | I‑58 |
| RSHLDWID | RIGHT SHOULDER WIDTH | Link | Num | I‑58 |
| RTE_NBR | ROUTE OR INVENTORY NO | Link | Char(5) | I‑58 |
| RTE_TYPE | STATE HIGHWAY DESCIGNATION NO | Link | Char(4) | I‑58 |
| RURURB | RURAL/URBAN CODE | Link | Num | I‑58 |
| S_FUNC | STATE FUNCT CLASS (1981) | Link | Num | I‑60 |
| SEATPOS | OCCUPANT POSITION IN VEH | Occupant | Num | I‑47 |
| SEG_LNG | SUBLINK LENGTH IN MILES | Link | Num | I‑59 |
| SEVERITY | ACCIDENT SEVERITY | Accident | Char(1) | I‑29 |
| SEX | OCCUPANT SEX | Occupant | Num | I‑47 |
| SIGNAL | TRAFFIC SIGNAL | Node | Num | I‑66 |
| SPDLMT | SPEED LIMIT | Accident | Num | I‑29 |
| ST_LIC | STATE OF LICENSE | Vehicle | Num | I‑39 |
| STR_NAME | STREET NAME | Link | Char(15) | I‑59 |
| SUBLINK | SEQUENCE WITHIN LINK | Link | Num | I‑59 |
| SURF_TYP | SURFACE TYPE | Link | Num | I‑59 |
| SURF_WD | PAVEMENT WIDTH | Link | Num | I‑60 |
| TEMPSEQ | *temp* DATA ENTRY RECORD ID | Interchange | Num | I‑77 |
| TOT_KILL | NUM K IN ACC | Accident | Num | I‑30 |
| TOT_NON | NUM NON‑INJ IN ACC | Accident | Num | I‑30 |
| TOTAINJ | NUM A INJ IN ACC | Accident | Num | I‑29 |
| TOTBINJ | NUM B INJ IN ACC | Accident | Num | I‑30 |
| TOTCINJ | NUM C INJ IN ACC | Accident | Num | I‑30 |
| TRF_CNTL | TRAFFIC CONTROL | Accident | Num | I‑31 |
| TRK_RTE | DESIGNATED TRUCK ROUTE | Link | Num | I‑60 |
| TYPEDESC | INTER TYPE + DESC | Node | Num | I‑66 |
| VEHNO | VEHICLE POSITION NUMBER | Vehicle | Num | I‑41 |
| VEHNO | VEHICLE POSITION NUMBER | Occupant | Num | I‑47 |
| VEHTYPE | TYPE OF UNIT | Vehicle | Num | I‑41 |
| WEATHER | WEATHER‑ATMOSPHERE | Accident | Num | I‑31 |
| WEEKDAY | DAY OF WEEK | Accident | Num | I‑31 |
| RODWYCLS | BY ACCTYPE | Accident |
| RODWYCLS | BY LIGHT | Accident |
| RODWYCLS | BY SEVERITY | Accident |
| RODWYCLS | BY WEATHER | Accident |
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| ACCTYPE | TYPE OF ACCIDENT | Accident | Num | I‑23 |
| ACCYR | YEAR OF ACCIDENT | Accident | Char(4) | I‑23 |
| ACC_DATE | DATE OF ACCIDENT | Accident | Char(8) | I‑23 |
| AGENCY | INVEST. AGENCY (?) | Accident | Char(5) | I‑23 |
| B_LINK | LINK=BOTH NODES (MOD) | Accident | Char(7) | I‑24 |
| CASENO | ACC CASE NUMBER | Accident | Char(9) | I‑24 |
| COUNTY | MAINE COUNTY KEY | Accident | Char(2) | I‑24 |
| C_HNODE | HIGH NODE | Accident | Char(5) | I‑24 |
| C_LINK | LINK=BOTH NODES | Accident | Char(12) | I‑24 |
| C_LNODE | LOW NODE | Accident | Char(5) | I‑24 |
| DAYMTH | DAY OF MONTH | Accident | Num | I‑25 |
| HOUR | HOUR OF ACC | Accident | Num | I‑25 |
| LIGHT | LIGHT CONDITION | Accident | Num | I‑25 |
| LOC_TYPE | LOCATION TYPE | Accident | Num | I‑26 |
| MILEPOST | DISTANCE FROM LOW NODE | Accident | Num | I‑26 |
| MONTH | MONTH OF ACC | Accident | Num | I‑26 |
| NONINT | NON‑INTERSECTION NODE ACC | Accident | Num | I‑26 |
| NUMVEHS | SINGLE OR MULTI VEH CRASH | Accident | Num | I‑27 |
| OBJECT1 | FIXED OBJECTS STRUCK | Accident | Num | I‑27 |
| RDCONSTR | ROAD CONSTRUCTION/MAINT | Accident | Num | I‑27 |
| RDSURF | SURFACE CONDITION | Accident | Num | I‑28 |
| RD_CHAR1 | ROAD CHARACTER | Accident | Num | I‑28 |
| RODWYCLS | ROADWAY CLASSIFICATION | Accident | Char(2) | I‑28 |
| SEVERITY | ACCIDENT SEVERITY | Accident | Char(1) | I‑29 |
| SPDLMT | SPEED LIMIT | Accident | Num | I‑29 |
| TOTAINJ | NUM A INJ IN ACC | Accident | Num | I‑29 |
| TOTBINJ | NUM B INJ IN ACC | Accident | Num | I‑30 |
| TOTCINJ | NUM C INJ IN ACC | Accident | Num | I‑30 |
| TOT_KILL | NUM K IN ACC | Accident | Num | I‑30 |
| TOT_NON | NUM NON‑INJ IN ACC | Accident | Num | I‑30 |
| TRF_CNTL | TRAFFIC CONTROL | Accident | Num | I‑31 |
| WEATHER | WEATHER‑ATMOSPHERE | Accident | Num | I‑31 |
| WEEKDAY | DAY OF WEEK | Accident | Num | I‑31 |
| RODWYCLS | BY ACCTYPE | Accident |
| RODWYCLS | BY LIGHT | Accident |
| RODWYCLS | BY SEVERITY | Accident |
| RODWYCLS | BY WEATHER | Accident |
NOTE: SAS variable names and longer explanatory names are shown above each listing. (See Discussion for information on SAS formats.)
*New codes added in 1997
NOTE: Inconsistencies in some categories between 1985-86 and later years due to coding change.
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NON-LABELED VARIABLE -- Used to link Accident File with Node File. See "Issues Related to Merging Files" in Discussion.
NON-LABELED VARIABLE
NOTE: This variable has nine characters. The first four characters represent year of accident.
NON-LABELED VARIABLE
NON-LABELED VARIABLE -- Used to link Accident File with Link File. See "Issues related to Merging Files" in Discussion.
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NOTE: Inconsistencies in some categories between 1985-86 and later years due to coding change. It is suggested that 1985 data not be used in intersection-related analyses.
NON-LABELED VARIABLE -- Used to link Accident File with Link File. See "Issues related to Merging Files" in Discussion.
NOTE: Inaccurate data. Do not use in analysis.
NOTE: Created variable added to HSIS accident and roadway inventory files in all states in 1999. See Discussion.
NOTE: Created variable based on the most severe injury to any occupant in the crash.
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| CASENO | ACC CASE NUMBER | Vehicle | Char(9) | I‑35 |
| CONTRIB1 | 1ST APPART CONTRIB FACTOR | Vehicle | Num | I‑35 |
| CONTRIB2 | 2ND APPART CONTRIB FACTOR | Vehicle | Num | I‑35 |
| COUNTY | MAINE COUNTY KEY | Vehicle | Char(2) | I‑36 |
| C_HNODE | HIGH NODE | Vehicle | Char(5) | I‑36 |
| C_LINK | LINK=BOTH NODES | Vehicle | Char(12) | I‑36 |
| C_LNODE | LOW NODE | Vehicle | Char(5) | I‑36 |
| DRV_AGE | DRIVER AGE | Vehicle | Num | I‑37 |
| DRV_INJ | DRIVER INJURY TYPE | Vehicle | Char(1) | I‑37 |
| DRV_SEX | DRIVER SEX | Vehicle | Num | I‑37 |
| MISCACT1 | PRE‑CRASH MANEUVER | Vehicle | Num | I‑38 |
| NUM_OCCS | NUM OCCUPANTS IN VEHICLE | Vehicle | Num | I‑39 |
| PHYSCOND | APPARENT PHYSICAL CONDIT | Vehicle | Num | I‑39 |
| ST_LIC | STATE OF LICENSE | Vehicle | Num | I‑39 |
| VEHNO | VEHICLE POSITION NUMBER | Vehicle | Num | I‑41 |
| VEHTYPE | TYPE OF UNIT | Vehicle | Num | I‑41 |
NOTE: SAS variable names and longer explanatory names are shown above each listing. (See Discussion for information on SAS formats.)
NON-LABELED VARIABLE
NOTE: This variable has nine characters. The first four characters represent year of accident.
NON-LABELED VARIABLE
NON-LABELED VARIABLE -- See Discussion.
NON-LABELED VARIABLE
NOTE: Higher than usual number of cases either uncoded or "unknown".
NON-LABELED VARIABLE -- This variable was created as a "check" variable to indicate the total number of occupants in the vehicle.
NOTE: The 1985 data is in error. In that year, 94% of the cases are coded as 99 = 'ALL OTHERS'.
NON-LABELED VARIABLE -- Vehicle Number in Crash (1-9)
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| AGE | OCCUPANT AGE | Occupant | Num | I‑45 |
| CASENO | ACC CASE NUMBER | Occupant | Char(9) | I‑45 |
| COUNTY | MAINE COUNTY KEY | Occupant | Char(2) | I‑46 |
| C_HNODE | HIGH NODE | Occupant | Char(5) | I‑46 |
| C_LINK | LINK=BOTH NODES | Occupant | Char(12) | I‑46 |
| C_LNODE | LOW NODE | Occupant | Char(5) | I‑46 |
| INJ | OCCUPANT INJURY TYPE | Occupant | Char(1) | I‑46 |
| SEATPOS | OCCUPANT POSITION IN VEH | Occupant | Num | I‑47 |
| SEX | OCCUPANT SEX | Occupant | Num | I‑47 |
| VEHNO | VEHICLE POSITION NUMBER | Occupant | Num | I‑47 |
NOTE: This file contains information on all passengers plus injured (but not injured) drivers.
NOTE: SAS variable names and longer explanatory names are shown above each listing. (See Discussion for information on SAS formats.)
NON-LABELED VARIABLE
NOTE: This variable has nine characters. The first four characters represent year of accident.
NON-LABELED VARIABLE
NON-LABELED VARIABLE -- See Discussion
NON-LABELED VARIABLE
NOTE: Approximately five percent of the data are uncoded.
NON-LABELED VARIABLE -- Vehicle Number in Crash (1-9)
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| AADT | ANNUAL AVGE DAILY TRAFFIC | Link | Num | I‑51 |
| AADTF | FACTORED AADT | Link | Num | I‑51 |
| AADTF_YR | YEAR OF CURRENT AADT | Link | Char(4) | I‑51 |
| AADT_TYP | AADT TYPE (EST. OR ACTUAL) | Link | Char(1) | I‑51 |
| AADT_YR | YR OF FACTORED AADT | Link | Char(4) | I‑52 |
| ACCESS | ACCESS CONTROL | Link | Num | I‑52 |
| A_HNODE | HIGH NODE OF LINK | Link | Char(5) | I‑52 |
| A_LINK | LINK=BOTH NODES | Link | Char(12) | I‑52 |
| A_LNODE | LOW NODE OF LINK | Link | Char(5) | I‑52 |
| BEGMP | POSITION WHERE SUBLINK BEGINS | Link | Num | I‑52 |
| COUNTY | MAINE COUNTY KEY | Link | Char(2) | I‑53 |
| ENDMP | POSITION WHERE SUBLINK ENDS | Link | Num | I‑53 |
| FED_AID | FEDERAL AID DESIGNATION | Link | Char(1) | I‑53 |
| FIFTY5 | POSTED 55/65 MPH ZONE | Link | Num | I‑54 |
| FUNC_CLS | FUNCTIONAL CLASS (1980 FEDERAL) | Link | Num | I‑54 |
| HPMS1 | HPMS SAMPLE SECTION | Link | Num | I‑54 |
| INV_CNTL | ROUTE TYPE INDICATOR | Link | Char(5) | I‑54 |
| JURIS | JURISDICTION | Link | Num | I‑55 |
| LENGTH | OFFICIAL SUBLINK MILEAGE | Link | Num | I‑55 |
| LSHLDWID | LEFT SHOULDER WIDTH | Link | Num | I‑55 |
| LSHL_TYP | LEFT SHOULDER TYPE | Link | Num | I‑55 |
| MVMT | MILLION VEHICLE MILES TRAVELED | Link | Num | I‑56 |
| NHS_CODE | NATIONAL HIGHWAY SYSTEM CODE | Link | Num | I‑56 |
| NO_LANES | NUMBER OF LANES | Link | Char(1) | I‑56 |
| ONEWAY | ONEWAY INDICATOR | Link | Num | I‑57 |
| PROBLEM | DISTANCE PROBLEM FLAG (CREATED) | Link | Num | I‑57 |
| RAMP | RAMP | Link | Num | I‑57 |
| RODWYCLS | ROADWAY CLASSIFICATION | Link | Char(2) | I‑57 |
| RSHLDWID | RIGHT SHOULDER WIDTH | Link | Num | I‑58 |
| RSHL_TYP | RIGHT SHOULDER TYPE | Link | Num | I‑58 |
| RTE_NBR | ROUTE OR INVENTORY NO | Link | Char(5) | I‑58 |
| RTE_TYPE | STATE HIGHWAY DESCIGNATION NO | Link | Char(4) | I‑58 |
| RURURB | RURAL/URBAN CODE | Link | Num | I‑58 |
| SEG_LNG | SUBLINK LENGTH IN MILES | Link | Num | I‑59 |
| STR_NAME | STREET NAME | Link | Char(15) | I‑59 |
| SUBLINK | SEQUENCE WITHIN LINK | Link | Num | I‑59 |
| SURF_TYP | SURFACE TYPE | Link | Num | I‑59 |
| SURF_WD | PAVEMENT WIDTH | Link | Num | I‑60 |
| S_FUNC | STATE FUNCT CLASS (1981) | Link | Num | I‑60 |
| TRK_RTE | DESIGNATED TRUCK ROUTE | Link | Num | I‑60 |
NOTE: SAS variable names and longer explanatory names are shown above each listing. (See Discussion for information on SAS formats.)
NON-LABELED VARIABLE
NOTE: Do not use for analysis. See AADTF.
NOTE: This is the more accurate definition of AADT and should be used in all analyses. Quality control checks have indicated that sections with "0" AADT are usually dead-end segments with few if any houses. Thus, the data are accurate.
Four-digit year; otherwise,
Four-digit year; otherwise,
NOTE: Do not use for analysis. See AADTF_YR.
NON-LABELED VARIABLE
NON-LABELED VARIABLE -- Used to link Accident File with Node File. See "Issues related to Merging Files" in Discussion.
NON-LABELED VARIABLE
NON-LABELED VARIABLE -- Created from "Distance from beginning of link" variable on raw file. Used in linking with Accident File.
NON-LABELED VARIABLE -- Created from "Distance from beginning of link" variable on raw file. Used in linking with Accident File. See "Issues in Merging Files" in Discussion.
ALTERNATIVE FORMAT NAME - $FEDAID
NOTE: This alternative formatting groups Federal Aid classes.
NOTE: Over 90% of the data in the 1990-97 files is coded as "0", which is defined as 'other' in 1999 guidebook. Based on inputs from the Maine staff in December, 1999, this variable is no longer coded or used. Maine has a "speed zone" file showing speed limits in approximately 6,000 miles of speed zones. HSIS programmers are trying to develop a linkage between this file and the Link File, but have not yet been successful. For special studies, manual linkage is possible.
NOTE: This is the 5th character of ROUTENO. For correct indication of official mileage, see LENGTH.
NON-LABELED VARIABLE-- This is a created variable which indicates "official" mileage. It is the same as SEG_LNG except that mileage on interchange ramps, on "Seasonal" roads, and on the opposing side of divided highways and toll roads is set to "0".
NON-LABELED VARIABLE -- Million Vehicle Miles Traveled on road segment
NOTE: Created variable added in 1999 for all HSIS roadway-inventory files. See Discussion.
NOTE: Checked with Maine staff in Dec, 1999. The data was collected after 1995.
NOTE: This variable is not totally accurate according to Maine staff. Use with caution. New variables with more accurate coding will begin with the 1998 data.
NOTE: This variable was created to indicate problems with the "Distance from beginning of link" variable. These problems would prevent the creation of accurate sublinks. For analysis and merging purposes, only those links coded "0" should be used.
NOTE: Created variable added to HSIS accident and roadway inventory files in all states in 1999. See Discussion.
(Width of right shoulder in feet.)
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NOTE: This variable is a combination of State and Federal rural-urban classifications. State is based on township boundaries and populations, and Federal is based on clusters of populations. Maine staff suggest using codes 1,3,5 to define "rural," and 2,4 to define "urban."
NON-LABELED VARIABLE -- This is a computed variable which provides the sublink length (or link length where there are no sublinks) in miles. It was obtained by subtracting BEGMP from ENDMP and dividing by 100. It may be used as a "weight" factor in producing tables with mileage. It includes both official and unofficial mileage. For "official" mileage, see LENGTH.
NON-LABELED VARIABLE -- Up to 15 characters giving name of street.
NOTE: New variable added in 1991.
NON-LABELED VARIABLE -- This is a created variable which was generated when links were subdivided into sublinks. The sublinks are numbered sequentially starting with "1". Thus, a value of zero indicates a link which was not subdivided (i.e., homogeneous throughout its entire length. This variable can be used to order the sublinks in increasing "milepost" order.
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| B_LINK | KEY FOR MERGING | Node | Char(7) | I‑63 |
| B_NODE | NODE NUMBER | Node | Char(5) | I‑63 |
| COUNTY | MAINE COUNTY KEY | Node | Char(2) | I‑63 |
| ENTVEHS | ANNUAL ENTERING VEHICLES (MILLIONS) | Node | Num | I‑63 |
| NBR_LEGS | NUM OF INTERSECTION LEGS | Node | Num | I‑63 |
| NODE1ST | NODE TYPE 1 | Node | Num | I‑64 |
| NODE2ND | NODE TYPE 2 | Node | Num | I‑64 |
| NODE_C1 | 1ST CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C2 | 2ND CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C3 | 3RD CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C4 | 4TH CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C5 | 5TH CONNECTING NODE | Node | Char(5) | I‑64 |
| NODE_C6 | 6TH CONNECTING NODE | Node | Char(5) | I‑64 |
| NO_APPR | NUMBER OF APPROACHES | Node | Num | I‑64 |
| RATETYPE | RATE TYPE (LOCATION CODE) | Node | Num | I‑65 |
| SIGNAL | TRAFFIC SIGNAL | Node | Num | I‑66 |
| TYPEDESC | INTER TYPE + DESC | Node | Num | I‑66 |
NOTE: SAS variable names and longer explanatory names are shown above each listing. (See Discussion for information on SAS formats.)
NON-LABELED VARIABLE -- Created from COUNTY and B_NODE. Used in linking with Accident File. See "Issues Related to Merging Files" in Discussion.
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NON-LABELED VARIABLE
NOTE: Inaccurate data. Should not be used in analyses.
NOTE: Intersection cases which are uncoded or coded "0" should be considered unsignalized.
If Node Type (NODET1) is 2 = 'Bridge',
NOTE: For intersection-related analyses, the variable LOC_TYPE on the accident file should be used to define intersection-related crashes, rather than TYPEDESC (To be more conservative, one might require agreement between the LOC_TYPE and TYPEDESC variables, after the interchange-related nodes are removed.)
*New code added in 1999, but applicable to prior years.
| SAS VARIABLE NAME | DESCRIPTION | FILE | SAS VARIABLE TYPE | FORMAT PAGE NO. |
|---|---|---|---|---|
| INTCHNG | UNIQUE INTERCHANGE NUMBER | Interchange | Char(7) | I‑71 |
| I_CNTY | COUNTY | Interchange | Char(2) | I‑71 |
| I_DESC | DESCRIPT NAME OF INTERCHANGE | Interchange | Char(30) | I‑71 |
| I_EXIT | EXIT NUMBER (optional) | Interchange | Char(2) | I‑71 |
| I_NE01 | 1st NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE02 | 2nd NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE03 | 3rd NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE04 | 4th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE05 | 5th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE06 | 6th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑72 |
| I_NE07 | 7th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE08 | 8th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE09 | 9th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE10 | 10th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE11 | 11th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE12 | 12th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE13 | 13th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NE14 | 14th NORTH/EASTBOUND NODE | Interchange | Char(5) | I‑73 |
| I_NECNT | NUMBER OF NODES ON NORTH/EASTBOUND SIDE | Interchange | Num | I‑73 |
| I_RTE | INTERSTATE ROUTE NUMBER | Interchange | Char(3) | I‑74 |
| I_SEQ | ASSIGNED SEQUENCE | Interchange | Char(2) | I‑74 |
| I_SW01 | 1st SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑74 |
| I_SW02 | 2nd SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑74 |
| I_SW03 | 3rd SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW04 | 4th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW05 | 5th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW06 | 6th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW07 | 7th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW08 | 8th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW09 | 9th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW10 | 10th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW11 | 11th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW12 | 12th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑75 |
| I_SW13 | 13th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑76 |
| I_SW14 | 14th SOUTH/WESTBOUND NODE | Interchange | Char(5) | I‑76 |
| I_SWCNT | NUMBER OF NODES ON NORTH/EASTBOUND SIDE | Interchange | Num | I‑76 |
| I_TOLL | TOLL BOOTH PRESENT? | Interchange | Char(1) | I‑76 |
| I_TOTCNT | NUM OF NODES FOR INTERCHANGE | Interchange | Num | I‑76 |
| I_TYPE | TYPE OF INTERCHANGE | Interchange | Char(4) | I‑77 |
| TEMPSEQ | *temp* DATA ENTRY RECORD ID | Interchange | Num | I‑77 |
NOTE: SAS variable names and longer explanatory names are shown above each listing. (See Discussion for information on SAS formats.)
NON-LABELED VARIABLE -- 'CCRRRNN' WHERE
NOTE: This is the same as the first two characters of INTCHNG.
NON-LABELED VARIABLE -- (OPT) INTERCHANGE NAME HAND-PRINTED ON MAPS
NON-LABELED VARIABLE -- (OPTIONAL) INTERSTATE EXIT NUMBER
NON-LABELED VARIABLE -- The four character node number for one of the nodes in the northbound or eastbound direction of travel. This will contain BLANKs for "Not Applicable".
NOTE: No particular order was used to collect the north/eastbound nodes for an interchange. Specifically, I_NE01 need not be the highest or the lowest numbered nodes. However, the nodes were entered without skips. Therefore, a blank value indicates the end of the node list. For convenience, the variable I_NECNT was created to indicate the total number of north/eastbound nodes at this location.
Before matching to the HSIS MAINE NODE FILE, a complete (10 character) NODEID must be constructed by concatenating the two character COUNTY in front and concatenating the character string '0000' to the end.
Before matching to the HSIS MAINE LINK FILE, a complete (10 character) LINKID must be constructed by concatenating the two character COUNTY in front and concatenating a higher numbered north/eastbound node to the end. Only some of the potential links actually exist in the "real world".
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_NE01)
NON-LABELED VARIABLE -- The number of non-blank nodes listed for the north/eastbound direction of travel.
NOTE: This is the same as the 3rd-5th characters of INTCHNG.
NON-LABELED VARIABLE --
NOTE: This is the same as the 6th-7th characters of INTCHNG.
NON-LABELED VARIABLE -- The four character node number for one of the nodes in the southbound or westbound direction of travel. This will contain BLANKs for "Not Applicable".
NOTE: No particular order was used to collect the south/westbound nodes for an interchange. Specifically, I_SW01 need not be the highest or the lowest numbered nodes. However, the nodes were entered without skips. Therefore, a blank value indicates the end of the node list. For convenience, the variable I_SWCNT was created to indicate the total number of south/westbound nodes at this location.
Before matching to the HSIS MAINE NODE FILE, a complete (10 character) NODEID must be constructed by concatenating the two character COUNTY in front and concatenating the character string '0000' to the end.
Before matching to the HSIS MAINE LINK FILE, a complete (10 character) LINKID must be constructed by concatenating the two character COUNTY in front and concatenating a higher numbered south/westbound node to the end. Only some of the potential links actually exist in the "real world".
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- (SEE FORMAT AND CODING UNDER I_SW01)
NON-LABELED VARIABLE -- The number of non-blank nodes listed for the south/westbound direction of travel.
NON-LABELED VARIABLE -- The total number of nodes listed for the interchange. This number is computed by adding I_NECNT and I_SWCNT.
NOTE: A sketch of various general types for interchanges has been included at the end of this section.
NOTE: In analyses involving only interchanges, screen out all records in which I_TYPE = 'REST', 'TOLL', or 'WGT'.
NON-LABELED VARIABLE
Sketch of interchanges here