Tag Archive: Colorado

Coincidence City

(Submitted by Skepticality listener Christie Greene)

I have a challenge for you. I was on a plane from Denver, my home, to Nashville to visit a college friend. She and I were roommates at a college in Nashville.

I was born in TN and moved to CO at age 23. I was in the center seat on the plane with a man next to me. We did not speak and were caught up in our books/computers/earbuds.

As we were descending into Nashville, we were told that we had to divert due to a weather event. The atmosphere in the cabin changed to something more relaxed, as so often happens when a diversion occurs from what is expected. At this point, this fellow and I began a conversation. I will stress here that if we had landed, said conversation would have never taken place.

The guy was from a city further west from Denver and had made a connection there. He was, at it turns out, flying into Nashville as his final destination, as I was. As we spoke, he told me that he was attending a funeral in a town not too far from Nashville. When asked which town (remember, I am from West TN), he told me the funeral was to be in a tiny town called Selmer. Selmer is actually about a 2 hour drive from Nashville.

I turned to him, astonished. I have an aunt, uncle and cousins who have basically lived in Selmer their whole lives. Wow, what a coincidence! But it gets better.

As we talked, he mentioned that he would be taking the ashes of the deceased to be scattered at a lake nearby, about an hour’s drive from Selmer. When I asked where this would be, I was floored by his answer. The lake and town to which he would be traveling with the ashes was Savannah, TN and Yellow Creek, a dammed area of the Tennessee River.

I graduated high school at Central High School in Savannah in 1981 (i only lived in Savannah for 4 years, mind you) and my extended family owned a small vacation home on Yellow Creek.

Okay, Skepticality, what are the odds?

Below are the extended notes provided by statistician and podcaster Kyle Polich for use in Skepticality Episode 272.  Take a look and leave your comments below. Also, please be sure to listen to the podcast for our own hilarious commentary.

(Kyle studied computer science followed by artificial intelligence in grad school with a focus in probabilistic reasoning and planning. His general interests range from obvious areas like statistics, machine learning, data viz, and optimization to data provenance, data governance, econometrics, and metrology. He enjoys exploring the intersection of statistics and skepticism and sharing related insights with others including through his podcast Data Skeptic. Visit Kyle’s blog Data Skeptic, and give the podcast a listen.)

Christie’s new acquaintance from the flight happens to mention his destination is the town of Selmer, two hours drive from their landing city of Nashville. He goes on to reference two other small towns, also within two hours of Nashville, to which Christie also has a connection.

Determining just how crazy these odds might be requires an understanding of how connected we are as people. I, for example, live in Los Angeles, California. I know people who live in Santa Monica, Culver City, Hollywood, Monterey Park, La Habra, Studio City, Pacific Palisades… I don’t know anybody from Malibu… anyway, what percentage of towns within two hours drive of me do I have a connection to?

I wrote a program that looks up that list of cities for any input. I generated a list of cities near a few of my friend’s homes and I asked them to tell me which municipalities they had some connection to. From this, I could come up with the frequency that people I know have a connection to cities near them.

To my surprise, I got extremely varied results. Some people had a connection to as few as 5% of nearby cities, while my highest scoring participant claimed to be connected to 70% of nearby municipalities.

Given my wide variety of results, I want to turn the tables on you, the listener. Guess for yourself, what percentage of municipalities within two hours of your home do you have a connection to? 10%? 50%? Think about it, and come up with a percent. Once you’ve got it, imagine you have a coin. But this coin is a weighted trick coin which comes up heads as often as your percent. So if you have few connections to nearby cities, say 1%, then on average, only 1 toss out of 100 is expected to be heads. Hang on to your imaginary coin, we’re going to be flipping that in a minute.

As far as we know, the gentleman in our story called out three cities in a row that Christie had a connection to. This is the equivalent of getting three heads in a row on your imaginary coin. That being the case, we can apply some basic binomial probability to this situation.

If you are connected to only 1% of nearby cities, than your odds are exactly one in a million. But I think that’s extreme. Most people are connected to more cities than that, especially in areas they grew up in. I have a connection to 40% of the cities within 2 hours of where I grew up near Chicago, so for me, the odds of 3 hits in a row are exactly 6.4%. And for anyone connected to only 10% of nearby cities, the odds drop to 0.1%.

So the exact degree of craziness in these odds relies entirely on how connected we are to people in cities that are around us. The less connected we are, the more surprising. I think assuming people are connected to 10% of the places within 2 hours of them sounds conservative and reasonable, so by that frequency, the chances are a bit small at 0.1%, or one chance in a thousand.

(Submitted by anonymous reader)

I was living in Santa Fe, NM and was dating a boy who lived in Boulder, CO.  He usually came to visit me but one spring weekend, I decided to drive up and surprise him.

I’d never driven to Colorado before.  I was 18 years old and the year was 1997, so there were no Maps apps or iPhones.  I have no idea if cars had GPS systems at this point, but mine certainly didn’t.

All I had to find him was an address.  The plan was to follow highway signs to Boulder and then ask gas station employees for directions until I found it.

I arrived in Boulder at dawn.  I drove down the main highway, hoping the street he lived on intersected it.  It looked like I’d passed all of the gas stations in town so I pulled over in an apartment complex so I could turn around and look again at the address I’d written down.

I glanced down at the paper and then up at the building directly in front of me…the addresses matched.  I had somehow driven directly to my boyfriend’s apartment without ever having been there before.  The main highway actually was the street he lived on, it just changed names once you get to town. (Something I never saw on any of the street signs.). I drove straight to him.  Amazing.

[EDITOR: I love this. We passed this one by Barbara who noted how many missing details and unknowns (including how much information she might have remembered, even subconsciously, that helped get her pretty close) make it difficult to quantify. But I can’t imagine how startled she had to be when she ended up in exactly the place she needed to be with no apparent guidance. Talk about what seems like an amazing sense of direction. Do that a couple more times and there’s no doubt you’d start to feel like you had some sort of superpower. – Jarrett]

Double Down on Old Friends

(Submitted by reader Deborah Warcken)

My Volkswagen squareback died in Evanston, Wyoming on its third trip to Colorado in February of 1972. From there G’Anna and I had to take the bus to Greeley where we stayed in my dorm from the previous school year. I had decided that Colorado winters were not for me and had retreated back to California to old friends and my horse. G’Anna was a new friend and had agreed to accompany me on a visit back during February break. I had several friends I wanted to see as well as a sister who had moved to Greeley the previous year. G’Anna had two friends in the Gunnison-Crested Butte area.

It was wonderful to see my friends from freshman year and visit with my sister and her family. I was disappointed because one of my best friends was no longer in school there. It was rumored that she had either returned to Ohio or was going to school elsewhere.

After our stay in Greeley we were able to rent a car and continue south and west to our next destination. This already had the makings of something of an adventure as G’Anna did not have an address or phone number for her two friends, Bill and Dirk. She said we would just have to hit all the local night spots and ask around at the ski area.

We arrived in Gunnison an hour or so before dark and started checking around. No one seemed to know her friends. It was suggested that we try up in Crested Butte so we drove up there and continued to check in the local hang-outs. Crested Butte is (or was) a small ski town and it was crawling with young people.

It was getting late and we’d just asked at the last bar in the village. All these places were fairly dark and this one was no exception. As we were heading for the door we passed some people coming in. It was too dark to see them clearly but something about one of them was familiar. After we got outside I had to turn and go back in to see if my sense was correct. It was! One of the people turned out to be my friend Laura who was supposed to be in Ohio.

I’m not sure which of us was more surprised, me, Laura or G’Anna. As we still had not found or even looked for a place to stay that night Laura let us stay with her. We decided to continue searching for Bill and Dirk the next day.

The following morning we went up to the ski area to continue our quest. Laura had to go to work at a little cafe but we said we’d stop back later and have some pie and say “goodbye”. G’Anna’s friends did not seem to be at the ski area so we made one last trip into Gunnison to look around in the daytime. No luck.

About mid-morning we stopped in and had some heavenly raspberry cream pie at the café and said goodbye and thank you to Laura. We started on our way out of town and were at the last stop sign before the beginning of the highway back to Gunnison. As we waited at the stop sign a car pulled forward from the other side and stopped to let out two hitchhikers in the middle of the intersection. You may have figured out already that these were none other than Bill and Dirk.