Week 10 Studio: Your personal false-alarm threshold

Students estimate the false-alarm rate at which they'd personally start ignoring or disabling a given alert, then compare answers to see how much the threshold varies person to person

26 April 2027

Before the studio#

No preparation required, but come having actually driven or ridden in a car with a lane-keeping or collision-warning feature at some point — a rental, a family car, a rideshare. If you haven’t, think of the noisiest notification system on your phone instead.

In the studio#

Idris runs a quick thought experiment individually first: for a lane-departure warning and, separately, a forward-collision warning, each student writes down the false-alarm rate at which they’d personally start ignoring the alert, and the rate at which they’d go further and disable it entirely — “1 in 3 chimes wrong” versus “1 in 20.” Answers go on the board under both alert names. The spread is usually wide, and that’s the point: the room then compares numbers and argues about why — does it depend on how the alert interrupts (a chime versus a seat vibration versus a full lane-tug), on what it costs to silence, or on how bad a missed real event would be. The session closes by asking whether a single manufacturer-chosen threshold can ever be right for a room this split.

Afterwards#

Keep your written thresholds — they’re a useful personal data point for arguing, later in the course, about whether a fixed regulatory threshold can ever fit every driver equally well.