Checkout Line Hypotheses: how to choose the fastest lane at the supermarket


It started with a math problem.
Dan Meyer, a Santa Cruz, California high school geometry teacher posted the photo, below, in his blog.

He put out the call to all of his friends (an equally math-loving cohort, it would seem): which lane would you choose?
It prompted endless discussion of variables and constraints, scalable models and linear regression (omga non-zero y-intercept).
The short answer: skip the Express Lane. More individual customers is slower than more individual items.
The real answer is that some problems resist logical solutions. There is no “all other things being equal” when dealing with human behavior.
There are still plenty of mathematics involved. Each item in a customer’s basket adds an average of 2.8 seconds to the checkout time. But each customer adds about 48 seconds before accounting for scanning a single item (How are you today? Do you have your Club Card with you? Will you be needing help to your car?….). That adds up to an extra 17 items that can be rung up before you would choose the line with an extra person.
There are a few hard and fast rules to help speed you on your way.
  • Check is slower than credit. Both are slower than cash. And look out for the lady with a fistful of coupons.
  • Lucky 13– the lines are almost always shorter if there is a Lane 13. Lots of superstitious people out there.
  • Watch the faffing, the waiting systems industry term to describe the stretch of time when the customer organizes their belongings after checkout has concluded. Faffing can drag on.
  • Prepare to wait in Washington D.C. With an average waiting time of 8:23, the supermarket lines are the slowest in the nation. (see map below)

And the surest way to stay out of the slow line? Steer clear if you see me in the market. I have an uncanny knack for picking the slowest.
[ Average wait times in grocery-store lines, in minutes]

Related Posts

Related Posts

6 Responses to Checkout Line Hypotheses: how to choose the fastest lane at the supermarket

  1. Aelie says:

    Excellent advice that puts numbers behind my general observations..thank you! I am, however, giggling at the idea of a grocery store with thirteen checkout lanes! I’ve seen that many at Fry’s, but there you can’t choose your lane 🙂

  2. Pingback: Finding the fastest Line in a Supermarket « Daniel C's Tech Beat

  3. Pingback: Choose Lucky Lane 13 For Speedy Supermarket Checkouts | Lifehacker Australia

  4. Cool post!Really enjoyed reading this.I followed you from the foodieblogroll and I really like what you have here

  5. Amy says:

    Great info and great post!

  6. Lori says:

    This is one of the best blog posts I’ve ever read. Altogether love your blog, Janice! Keep up the great work. 🙂

Leave a Reply

Is it appropriate conversation for the dinner table? Then it should be fine.

Web Analytics