Product Overview - Network Screening Segments
The Network Screening application is designed to help users rank and identify sites for further investigation and potential treatment along the entire roadway network in an easy-to-use interface. The Network Map displays the ranked segments/intersections, color coded according to standard deviation. With Green representing the lowest value, yellow representing the mean (+1 standard deviation), and red representing the second standard deviation (Mean + 2 standard deviation).
(A network screening, with the Network Map displaying the ranked segments)
The Network Screening application has 5 key features: Attribute Search, Segment Flyout, Roadway Ranking, Contextual Data, and the Network Screening Report. Each feature is discussed in more detail below.
Rank your selected roadway by the following ranking criteria:
Crashes per mile
SPF Predicted Rate*
EB Expected Rate*
PSI Potential Rate*
SPF Prediction Per Mile*
EB Expectation Per Mile*
PSI Potential Per Mile*
(* indicates that an agency specific SPF is required for this calculation. SPFs can be generated, and managed through the Predictive Analysis application)
A comprehensive list of how each ranking criteria is calculated can be found in the Numetric Calculations Overview article.
Network Screening - Segments will only load the top 1,000 segments that meet your ranking and filter criteria. A more comprehensive list of all intersection rankings is available in the CSV download.
(A segment ranking window with the selected segments ranked by Crash Rate, with Crashes Per Mile also displayed.)
Each ranking criteria can be modified to include a limited ranking value. When defined, only segments with a value that meets or exceeds the defined minimum value will be displayed in the ranking table, and screening map. By default each value is set to 0, meaning that every segment will be displayed. To modify the limiting value, click the Settings button located in the top right corner of the screen, next to the Save button, and enter the minimum value for the desired ranking criteria.
(The Settings flyout with the Limiting Values displayed. In this example, a minimum number of crashes is being defined as 3, meaning only segments with 3 or more crashes will display.)
Use Numetric’s powerful text-to-search feature to run custom roadway Network Screening requests. Search by recommended countermeasure, crash type, or any other crash or roadway attribute, and generate instant roadway rankings that tell you which roadways require your attention.
(A Segment Screening for a given county displaying roadway ownership, ranked by Equivalent Property Damage Only (ePDO).)
Clicking on the Map Settings icon (the gear icon located in the top right corner of the map), will allow you to customize your map settings, including the auto-zoom, and satellite view. These settings will save and become your default map settings whenever you login.
(The Map Settings section of a Network Screening map)
Clicking on any segment in your network displays the Segment flyout, which contains current, and historical segment rankings, crashes by milepoint, a summary of crash statistics (including number of crashes and fatal (critical) crashes, crash ratio, crash rate, crashes per mile, and location information), a summary of roadway details (including AADT, function classes, and any other roadway datapoint present in your data), and a list of recommended countermeasures for that segment.
(A Segment flyout showing the current state ranking of the segment, as well as the crashes by milepoint, grouped by severity.)
With photos and Google Streetview, users can explore selected segments, and even see how each segment has changed over time, all without leaving the app.
(A Segment flyout showing the current and historical state-wide ranking, as well as a link to open the selected segment in the Safety Analysis application.)
Network Screening Report
Generate a downloadable Network Screening Report which contains the network ranking, and a breakdown of each segment, including the crash rate, crash ratio, crashes per mile, fatality rate, and serious rate, and distribution of crashes along the segment grouped by severity, as well as a stacked bar chart indicating the mile point at which the crashes occurred.
(A sample Network Screening Segment Report.)