Home Intro Tutorials Articles Rest API Contact
Sign in Demo

What is intersection analysis?

Intersection Analysis lets you inspect traffic at a junction or roundabout directly from the Visual Analytics page. Instead of looking only at individual road segments, it presents the connected roads around a selected intersection in a diagram.

There are two analysis modes:

  • Approaches shows incoming and outgoing values for each connected road. Use it to compare traffic volumes, speed or other available attributes at an intersection.

  • Turns shows how trips arriving from one road continue towards the different outgoing roads. Use it to investigate left and right turns, straight-through movements and movements through roundabouts.

Intersection Analysis showing incoming and outgoing approaches

For example, you can answer questions such as:

  • "Which approaches carry the most traffic into this intersection?"

  • "How do incoming and outgoing volumes compare?"

  • "What percentage of trips arriving from this road turn left, right or continue straight?"

  • "How do approach or turning-movement volumes change over time?"

From road-network data to intersection insights

To perform intersection analysis:

  1. Prepare a road network. Create a line-based data set with a connected road-network graph. Its segments must have start node and end node identifiers configured as the corresponding edge content types.

  2. Choose the appropriate data type. Approaches supports Geometry, Time Series and Movement Path data sets that use the graph-enabled road network. Turns requires Movement Path data, with trips represented as sequences of road segments on that network.

  3. Select an intersection. Open Visual Analytics, activate intersection analysis for the supported road-network layer and point to an intersection or roundabout on the map.

  4. Analyze and share. Inspect the Approaches or Turns diagram, apply the layer’s filters and time range, open Trend Analysis, add a dashboard widget or export an image.

Ordinary Movement (such as raw FCD GPS data) or Points data sets do not provide the graph-based intersection analysis described here. Movement Path data represents trips along a road network rather than as a sequence of independent GPS locations.

Read Configuring your data set for intersection analysis before continuing to the individual analysis modes.