It may be the biggest moment “for potty parity that we have seen, to have two big facilities open at the same time, and all these restrooms open at once,” said Kathryn Anthony, a professor of architecture at the University of Illinois and a board member of the American Restroom Association.
The new Yankee Stadium and Mets’ ballpark will adhere to new laws in place in New York City requiring two women’s toilets for every one men’s toilet. Read about it here in the New York Times (via The Browser.) Empirically, a woman’s visit to the stall lasts twice as long as a man’s on average so the ordinance is intended to equalize waiting times for men and women. A few thoughts come to mind (double-entendres noted in parentheses).
- This will actually overshoot (!). The waiting times will be equalized only at times of peak demand when queuing occurs. If women have more stalls than men, they will queue less often. As a result average waiting times will be lower for women than for men.
- We should not be equating waiting times anyway, we should equate the marginal cost of an additional fixture relative to the resulting reduction in average waiting times. Urinals are cheaper than stalls.
- There is a moral hazard problem coupled with an externality that is not being taken into account. When queuing is a possibility, the patron trades-off the instantaneous urgency versus the alternative of waiting for off-peak moments, for example avoiding the seventh-inning stretch. If prices could be charged, Ramsey pricing would dictate that prices would be positive only at times of peak-load (!). This is to encourage the less urgent to wait for the off-peak reducing the externality imposed on others. When prices cannot be charged, some level of congestion will be part of a second-best (number two !) incentive instrument.
- In queuing problems in general, it is efficient to first serve those whose needs require the shortest use of the facility because they impose the least externality on others. This principle points toward disparity in favor of men.
- I hope they have looked into this.

3 comments
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April 16, 2009 at 1:17 am
Alanna
Wouldn’t the most efficient thing be making all bathrooms unisex, eliminating any difference in wait time between genders?
April 16, 2009 at 1:25 am
Anonymous
I enjoyed reading your arguments but still have a few concerns:
1. I don’t think your first point is necessarily true. It depends on the distribution of waiting time and queues and It is possible to have distributions for which the argument is false.
2. On your second point, I completely agree that the efficient allocation of resources is when the golden rule of marginal costs and benefits holds. But the question is, is this fair? Nobody chooses his/her gender, so why should someone wait on average (even a bit) longer for all her life just because of her gender (which she had no control over). Also, it is difficult to compute the marginal cost of waiting since it is different across individuals and more importantly across time.
3. This is exactly the same moral hazard problem that men face. It is necessary that men and women face the same level of incentives to avoid moral hazard problem, i.e. the same marginal cost. The problem that I want to acknowledge is that if they double the number of restrooms, the waiting time may not cut in half on average or in the peak times, since as you said, people face a different moral hazard problem and the number of people who choose to go to bathroom during the peak time may increase.
4. I have absolutely no problem with point 4 except that men and women are not using the same bathrooms (are not standing in the same queue). In other words, men cannot affect the externalities imposed on women.
BTW, your blog is fantastic.
April 16, 2009 at 1:59 pm
jeff
nice comments and thanks for the endorsement. on 1,i was assuming symmetry in arrival process and that women take 2 minutes, men take 1 minute
also, i spotted a double-ententre in there that you could have flagged.