You are viewing this article in the AnnArbor.com archives. For the latest breaking news and updates in Ann Arbor and the surrounding area, see MLive.com/ann-arbor
Posted on Wed, Dec 8, 2010 : 10:08 a.m.

How to snag deals in Ann Arbor on your birthday, 2010 edition

By Edward Vielmetti

Today is my birthday. I wrote about my 2009 birthday, in a post entitled "Birthday deals, bagels, breakfast, and draining the Argo mill pond"; this is as much as any a repeat of the same routine.

The Arborwiki Birthday Deals page is a must-read for your birthday; it details, lovingly, the places that will give you a good deal on your birthday. I had breakfast at the Northside Grill, and then stopped at Zingerman's Deli for a half dozen free bagels. Ann Arbor is one of the best cities I know in which to have a birthday, and one fearless gastronome managed to score eleven separate birthday treats on her recent special day.

Like last year, I visited Argo Park and the Argo mill race. The water level on the mill race is noticeably lower than last year, below the level of the spillway and of the grate below it that drains that pond. There are a few solid inches of ice at the pond's edge, not enough to give me confidence to walk across the whole pond but enough to remind me that once it does ice up it could be a good place for ice skating or cross country skiing across the ice. This looks to be the last year of that mill pond, given a November decision by City Council to repair the Argo embankment and to put in whitewater features.

Like last year, snow is on its way, with the weather forecast predicting up to 2 inches on Thursday night. The National Snow Analysis shows western Michigan with substantial lake effect snow, and southeastern Michigan with only sprinkles. I'll look ahead to enough snow for good sledding, which came by mid-December last year.

The birthday problem (Wikipedia) asks you to compute the probability that two people in a room have the same birthday. Surprisingly, you need only 23 people in the room until there's better than a 50 percent chance of two sharing the same date.

I looked, but didn't find, a statement for a similar problem: how many friends do you have to have for it to be likely that you can celebrate a birthday every day? By my naive calculation, at 1,000 friends, you have about a 6 percent chance that no one will have a birthday today; at 2,000 friends, that probability goes down to 0.4 percent. If you know how to model this problem and solve it, I'm interested.

Edward Vielmetti collects friends and acquaintances so that he can celebrate a birthday every day for AnnArbor.com.

Comments

joey

Thu, Dec 9, 2010 : 11:37 a.m.

hey donald, surprising how many people take advantage of businesses trying to do the right thing.

Donald

Wed, Dec 8, 2010 : 2:33 p.m.

You can get a half sozen free bagels @ Zingerman's Deli, AND Another half dozen at Zingerman's Bakehouse

Dan1737

Wed, Dec 8, 2010 : 12:55 p.m.

This seems to cover it well, if not briefly: http://en.wikipedia.org/wiki/Wikipedia:Reference_desk/Science/Birthday_probability_question