Pure speculation: could be that poor kids were more likely to have dealt with similar problems or even just to have dealt with similar levels of suffering, and therefore respond with a little more short-term resilience.
Not like anyone can do follow-ups on this research any more.
Crying loud is a pretty good mammal trick for most situations other than an imminent predator-grabbing - being trapped in an airtight refrigerator is definitely an evolutionary edge case.
Agreed. Although one option would be to require all two year old children to escape a refrigerator or die trying, in order to evolve out of this problem.
Put a microphone inside and outside the fridge. If the noise coming from inside the fridge is louder than the noise from outside the fridge, pop the hatch automatically.
Not a viable solution for 1958x but today we are talking about a few dollars in electronics and an electromagnet.
Not a viable solution today: the problem is not fridges in active use in houses, it's fridges in people's backyards/dumps/barns/whatever where they are no longer plugged into anything.
A battery could presumably power it long after being unplugged. But you're right - That article basically states that the problem was solved in 1958, by replacing the mechanical latch with a magnetic door. Coincidentally this research was from 1958, so I assume there is a connection there. Thanks for posting that - It puts thing into perspective.
You could probably use a single mic and a volume threshold, rather than a volume comparison with the outside, unless enough sound from the outside of the fridge gets to the internal microphone to set it off (e.g. during an earthquake or extremely loud party).
Though this is straying a bit from the topic at hand, I must point out that quality speakers employ a range of designs, from simple sealed designs, to the ported designs you mention, on up to folded or full-scale (built with cinder block walls[0]) subwoofer horns.
The purpose of the port in ported designs is not just to allow movement of air, but to control the resonant frequency and Q-factor of the speaker. The individual dimensions, size, shape, and materials of quality speaker enclosures are all tuned to control resonance.
To sum up, there's a lot more to it than "an airhole to allow movement of air."
The generalization of statistics is relatively recent development in science. AFAIK, it happened during the 50's and 60's, probably at a different pace in different disciplines.
The bit that worries me is the percentage of children who locked in the fridge just waited and cried.