What the Sensors Actually Measure
Every driver score is built from a handful of physical measurements. Knowing which, and how they are derived, explains most of what goes wrong later.
Explainer
What is measured
Every score is a weighted sum of event counts divided by exposure. Each of those three parts introduces a distortion, and the route usually dominates all of them.
8 notes
Thresholds and What They Decide
An event exists because a threshold was crossed. Where that threshold sits determines the entire output, and it is usually a default.
Analysis
How a Score Is Built
A driver score is a weighted sum of event counts divided by exposure. Each of those three parts introduces a distortion.
Analysis
The Statistics That Mislead
Four effects that make driver scores look more informative than they are, and how each shows up in a real fleet report.
Analysis
What Actually Predicts a Collision
The honest position on the evidence, and why the strongest predictors are not the ones the products measure.
Analysis
Whether the Data Is Any Good
Four checks that show whether the events and scores will bear weight, and what each means when it moves.
Procedure
The Question to Ask First
One question that sorts most decisions in this field, and what each answer means.
Analysis
The Four Things
If nothing else in this collection is done, these four, in this order, with what each prevents.
Reference