This tutorial will walk you through drawing a Calibration Zone Set. Our Calibration Feature is a great tool for users who want to get estimated vehicle, bicycle, or pedestrian counts rather than our StreetLight Index. Calibration using your own count data is a feature offered to all users of StreetLight InSight.* These Zone Sets with Calibration data can be used in the following Project Types: Zone Activity Analysis, O-D Analysis, O-D with Middle Filter Analysis (not available for pedestrian), and O-D to Preset Geography. To learn more about how to create a Calibrated analysis, check out our solutions guide. If you'll be running a bicycle or pedestrian project, learn more in our solutions guide specific to those modes.
*If your subscription is from before January 1, 2019, it may not include the Single Factor with StreetLight AADT Calibration Type. Also, bicycle and pedestrian modes are only available in our Multi-Mode subscriptions. Contact email@example.com if you would like to get access to these features.
There are two ways to add calibration data to a Project: By using local count data in a Calibration Zone Set or by using StreetLight Data’s AADT Metrics. As with any Project in StreetLight InSight, the first step of using the Calibration Feature is to create a Zone Set, in this case, a Calibration Zone Set. For this tutorial, we will go step-by-step to help you set up a Calibrated Zone Set by drawing your Zones and uploading local count data.
Note: The Calibration Feature utilizes additional data and analytics to scale StreetLight Index values to estimated counts. Learn more about how our Single-Factor calibration works. There are two options:
- “Single Factor with User-provided Counts ”: Uses user-provided and uploaded AADT (or similar counts) data for roads in or similar to your study area for calibration.
- “Single Factor with StreetLight AADT”: Uses our AADT values as your calibration data set.
What is a Calibration Zone Set?
Calibration Zone Sets are comprised of at least one Pass-through Zone. The Zone can either be a small polygon Zone (like a gate) or a line segment Zone drawn to cover a road or path. You will use this Zone Set when running your Projects in order to calibrate our Metrics to give you estimated counts. If using “Single Factor User-provided Counts,” then creating the Zones follows our typical process, but with an extra step: adding the calibration data. Remember that these Zones can be created by either drawing or uploading, but in this article, we will focus on how to draw a Zone Set and add the calibration data manually.
- It’s perfectly fine to have a Zone Set where some Zones have calibration data and some do not. It’s also fine to have a Calibration Zone Set with anywhere from one Zone to 100+ Zones.
- If you are calibrating with "Single Factor with StreetLight AADT" you will not need to add calibration data manually. Learn more about calibrating with StreetLight AADT.
Draw a Calibration Zone
Heads Up: When you create a Calibration Zone Set by drawing Zones, you will need to add local data to each new Zone individually. The following step-by-step guide will show you the process for a single Zone. Repeat this process as many times as necessary to create your Calibrated Zone Set.
Step 1: Create a new Zone Set, name the Zone Set, choose the Zone Set Type as desired.
Step 2: Draw and name your Zone. Learn more.
Step 3: Mark your Zone as Pass-through.
Add Calibration Data to a Pass-through Zone
After marking the Zone as pass-through, a checkbox for “Calibration Data” will appear. Check the box to add your local traffic count data. Reminder, if you are calibrating using StreetLight AADT, you do not need to upload local traffic count data for calibration.
Step 1: Enter your traffic count data. Fill out the fields as follows:
- Calibration Type: Select whether your counts are AADT, ADT, AWDT, or AAWDT.
- Calibration Value: Input the traffic counts for the specific Zone
- Personal Traffic Ratios, Commercial Medium Duty Traffic Ratios, and Commercial Heavy Duty Traffic Ratios: If you have information on the breakdown of traffic input it here. If not, use the default settings.*
- Optional Fields: There are two optional fields available so that you can add information about the collection methods used and any other notes that are important for your Project.
*This breakdown will only apply to Projects that use Navigation-GPS as a data source.
Note: The default travel mode is Vehicles. Select the Bicycles or Pedestrians tab to add AADBT or AADPT values respectively. You may also add notes. If calibrating with one of these modes, be sure to choose its respective OSM layer when drawing the zone.
Step 2: Click “Save”.
Step 3: Continue to draw additional Zones and add the calibration data following the same steps as above to complete your Calibration Zone Set. Once the Zone Set has been saved, you’ll be able to use this as a Calibration Zone Set when setting up Project.
- Try to use calibration zones that are similar to your analysis zones, i.e., use interstate calibration zones if studying an interstate.
- We recommend you save the Zone Set after creating the first Zone and then editing the Zone Set to add more Zones. This approach will prevent loss of effort in the event of an interruption to the session.
- If you already have a Zone Set saved in your StreetLight InSight account that is not yet used in a project, you can turn it into a Calibration Zone set by editing it and adding local traffic count data for any applicable Zones. You do not have to create a new Zone Set.