Why does the Canada Post driver leave you a delivery notice without attempting to deliver your package, how can it be fixed?
In an hour or two, I will be walking downhill for about a kilometer to pick up a package that was supposed to deliver yesterday. Despite being home all day, all I got yesterday was a scrap of paper asking me to pick up myself. It is a common occurrence for me here in Canada but I don’t recall similar experience with USPS while in the US.
The delivery system is clearly not working as intended. Otherwise, a more efficient method would be to just email the recipients the pick-up notices instead of having someone load and offload packages, drive up to each doorstep loaded with packages, only to deliver a piece of paper.
What caused the problem and why does it only happen in Canada? The answer lies in the incentives. With Canada Post, there will only be a single attempt at delivery before pick up. With USPS, three attempts will be made. A Canada Post driver, upon arriving at the address, has no incentive to deliver the package: she can just drive off and offload at the end of day and never have to worry about it again. For a USPS driver however, a missed delivery means she will have to visit the same address again the next day. Therefore, she actually prefers to deliver the package instead of leaving the slip.
The solution then, seems simple: if a driver must make multiple attempts before the recipient must pick up the package, the driver has an incentive to make a delivery on every attempt except the last.
Note that the last delivery attempt is always a “show attempt” (as long as the driver is aware of it being the last) serves only as a cost to the driver for having failed to deliver sooner. Additionally, the probability of a successful delivery is likely to decrease conditioning on previous attempts having failed. A natural question to raise would be whether forcing additional attempts on drivers is worth the cost, and if so, how many attempts is optimal. Below we build a simple model to analyze it.
Let the cost of each delivery attempt be c, and the cost of recipient pick up be d. Because of expertise (Canada Post has a truck that the recipient doesn’t) and economies of scale (the driver can plan routes more efficiently because she has multiple deliveries to make in a given location), d>c. Let the probability of successful delivery at first attempt be p>0. Finally, assume all packages will end up either being delivered or picked up (the only strong assumption here, I think). First let us compare the cost of One Attempt Approach (1AA) with Two Attempt Approach (2AA):
The cost of 1AA is simply c+v (the only attempt is always a show attempt, and all packages are picked up). The cost of 2AA: c+(1-p)(c+v). This expression will show up in more than one place, so it is worth contemplating a bit. Whether introducing the second attempt is worthwhile depends on whether v>[(1-p)/p]*c. A big enough p (and definitely when p>=0.5) justifies a second attempt. As p approaches 0, a second attempt is not justified. Thus, as p takes on different values between 0 and 1, both conclusions can be reached (this is a nice feature, it provides a unique finite solution later).
Now compare 2AA with 3AA. Let q be the success rate of second attempt conditioning on first attempt failed, q<p. Then the cost of 3AA is c+(1-p)c+(1-p)(1-q)(c+v). A third attempt is justfied if the cost is lower than 2AA. Rearrange to get v>[1-q)/q]*c.
Note the similarity between the previous two comparisons. As the probability decrease with additional attempts (and with sufficiently large number of attempts, the probability goes to 0: if we made 5000 attempts at delivery at an address and failed every single time, how can we expect the 5001th time to be successful?), we will eventually reach a point where additional attempt is no longer justified, yielding a unique optimal number of attempts.
However, even if p is so low that the second attempt is not justified, the One Attempt Approach currently employed by Canada Post is suboptimal, given our previous discussion of emailing delivery notices.
Having established that there exists more efficient delivery systems, the question now, is that why Canada Post have not adopted them? I suspect it is related to regulations (labor laws?) or the recent strike. Both of which I am not familiar with. Some quick Google searches did not yield any definitive answers either. If anyone familiar with the matter can shed some light it would be greatly appreciated.
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