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Part 3 of 7 · Parking permit issuer series ~6 min read

How allocation gets decided without a riot

There is no allocation rule that everybody thinks is fair, and there is a large difference between a rule people disagree with and a rule people cannot see.

Key takeaways

  • Four common rules; each rewards something different and none is neutral.
  • Publishing the rule in advance matters more than which one it is.
  • Show the waiting list position; an invisible list is assumed to be rigged.
  • Accessible need is not an exception to the rule; it sits outside it.
  • Record every allocation decision against the rule that produced it.

Four rules

RuleRewardsComplaint it generates
Distance from public transportPeople with no alternative“I live further away but have a station”
BallotNobody; it is random“I have been here twelve years”
Seniority or length of serviceTenure“I need it and they do not”
First come, first servedSpeed of response, and whoever was told first“I did not know applications opened”
Need, assessedGenuine circumstances“Who decides what counts as need?”

Each of these is defensible and each produces a specific complaint, and the complaints are predictable enough to be worth reading before choosing. The distance rule is the most common and produces the most edge cases; the ballot is the most obviously fair and the most resented by long-serving staff.

A combination is usually what happens in practice: a small number allocated on assessed need, the rest by distance or ballot, with a stated proportion for each. That is fine as long as the proportions are published too.

Publishing beats optimising

How parking permits are allocated under a published ruleA vertical chain of five steps entered by a box labelled Permits to allocate, eighty-one of them. Step one publishes the rule two weeks before applying, with a side box noting it includes the tie-break. Step two opens applications for a stated window. Step three applies the rule mechanically. Step four records why each decision was made against the rule. Step five publishes the outcome as counts rather than names. A note says every step here is about being checkable and none of it is about optimality.AWS ACCOUNTPermits to allocate81 of themPublish the rule2 weeks before applyingIncludingthe tie-breakApplications opena stated windowApply the rulemechanicallyRecord why eachagainst the rulePublish the outcomecounts, not namesEvery step here is about being checkable, and none of it is about optimality.
Fig 1. The allocation process. Each step exists to make the outcome defensible rather than better.
  • Compute
  • Database
  • Management
  • Analytics
  • Front-end & mobile

The tie-break

The rule needs one and it needs to be published with the rule, because the tie-break is where a mechanical process becomes a judgement if it has not been decided in advance. Two people equidistant from the office, applying on the same day, need a stated way of being separated.

A random tie-break is the honest answer and it should be described as random rather than dressed up. “Ties are resolved by a draw” is something people accept; a tie resolved by something unstated is not.

Publishing the outcome

Counts, not names: how many applied, how many were allocated, the distance threshold that resulted, the number allocated on assessed need. That lets anybody check that the rule produced the outcome without publishing who parks where.

It also removes the most common suspicion, which is that more permits were issued than were announced.

The waiting list

How a parking permit waiting list is run and shownA horizontal row of five boxes. Fifty-six on the list, ordered by the rule. Position visible to each person. Movement visible: you were thirty-four, now twenty-seven. Offers in order, recorded. Declines keep position, or go to the back? State it. A note says an invisible waiting list is universally assumed not to move at all.THE LIST HAS TO BE VISIBLE56 on the listordered by the rulePosition visibleto each personMovement visible'you were 34, now 27'Offers in orderrecordedDeclines keep positionor go to the back?state itAn invisible waiting list is universally assumed not to move at all.
Fig 2. How the waiting list works. Visibility of position and movement is what stops the list being assumed to be decorative.
  • App integration
  • Analytics
  • Front-end & mobile
  • People

The last box is a real decision that has to be made in advance. Somebody offered a permit in November who does not want one until they move house in March: do they keep their position or go to the back? Both are defensible and only one of them can be the rule.

What is not an exception

Sitting outside the rule entirely

  • Accessible bays are allocated on need, are not in the permit pool, and are not subject to the ratio.
  • Temporary need — an injury, a medical course of treatment, a pregnancy — gets a temporary permit outside the allocation, with an end date.
  • Operational vehicles are not permits.
  • Visitors have their own spaces and their own process.
  • These are not exceptions to the rule. They are outside it, and describing them that way removes the sense that exceptions are being made.
  • Temporary permits have end dates that are enforced, kindly, with a reminder and a way to extend.

The framing in the fifth line does real work. “An exception was made for X” invites the question of why not for me; “accessible bays are allocated on need and are not part of the permit scheme” is a description of a different thing.

Next: the permits nobody uses.

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