Monday, March 19, 2007

speech fire alarms

I heard today about a new product that claims to be a more effective smoke/fire alarm. Instead of a siren, the alarm is a recorded voice. The idea is that when little kids wake up to an alarm, they are disoriented and confused. To hear specific instructions coming from their mom's voice is supposed to be helpful. The recording can be more than just "wake up." It can have detailed instructions like "There is a fire!! Get up and go out the back door right away!!!"

But I am conflicted on whether this is really better. I think that from a pure sensory salience perspective, there is not way that a voice is as loud or alarming as a siren. Also, the mom's voice is a common thing, so they won't instinctively associate it with an emergency. If they are sleeping, they may not hear enough of the voice to know it is the fire alarm. Also, as early as 10 years old, I am sure kids are trained to ignore their mom's voice waking them up: "Mom, I don't want to go to school today."

So the tradeoff is that a siren is better to wake them up and the voice is better to remind them of where to go. So which is more likely, that they fail to wake up or that they panic and forget where to go? I don't know this answer, but I suspect that the designers did not do the study to find out either. They guessed that this would be better and the lives of thousands of children will depend on them being correct. I hope they are.

airline pilot pay

The salaries of airline pilots is a great example of a way to structure pay that is misaligned with performance. The hardest part of flying is takeoff and landing. So if salaries is based on the task difficulty, then short haul pilots would get paid more. But in fact it is the opposite.

I suspect that these salaries are based on the size of the plane. Long haul flights generally have bigger planes. This could make a little sense if it is based on responsibility - more people in the plane = more people relying on the pilot's skills. But if takeoff and landing are really the hard parts, then many smaller flights still has more responsibility.

Or, they are influenced by seniority. Since longer flights are easier (the plane mostly flies itself), more senior pilots get them. Basing pay on seniority is somewhat controversial. It is common in unionized organizations. It makes sense to reward employees for staying at the company, especially in industries where there is tacit knowledge that makes the employee better at his/her job. But I personally think it is better to link the salary to this tacit knowledge directly - not the predictor of job tenure.

But this is a good example of the complexity of the real world. If pay were structured based on what really motivates performance (long term and short term), seniority would have some impact, but not nearly as much as it does. Politics and other non-engineering factors still play a large role.