'Agression Detectors' Don't Work When Spying On Students
It seems like a technical solution that might work, albeit intrusively. A sensor listens to the tenor of student conversation, and tries to predict anger and then violence.
(Sound Intelligence aggression detection)
Developed by Sound Intelligence, the monitors are fixed in public spaces like hallways and cafeterias, listening for shouts or tension — and for an extra added price, they’ll listen for gunshots, car alarms, and even recognize if “students are vaping in the school bathroom.”
One student let out a glass-shattering scream in a silent library, which didn’t set off the detector, but a sick student coughing through a chest cold did. During another test, when the students cheered on a pizza delivery or were playing a calm game of Pictionary, the detector went haywire with warnings.
The machine learning algorithm within the device picks up on high-pitched, strained noises but doesn’t analyze the words or meaning of what the person is saying. When it detects aggression, a message will pop up declaring “StressedVoice detected.”
Science fiction readers have been acquainted with this idea for some time, having read about decibel alarms in Anne McCaffrey's 1973 novel A Bridle for Pegasus:
Decibel alarms were legally required in every meeting hall, including churches, but clever agitators could and had sabotaged them so that the suppressant gases were not released when the "noise" level reached the sharp pitch of incipient riot. The professional agitators had also learned how to modulate their voices below the danger level, carefully goading their victims into the spontaneous combustion which neither gas nor water jets could control.