## Similar Soldiers

(Submitted by reader Robert Wilson)

I joined the Royal Australian Air force in 1972. During the ’70s recruitment was high, so it was not uncommon to have  flights of 20(ish) trainees graduating each week or so. On my first pay parade (we all got paid in cash after a lengthy line up) we all stood at-ease awaiting our name to be called out.

When the paymaster shouted out our names, family name first, first name last, we would then snap to attention and march forward for our pay.

This is how it went:

“Wilson, Robert”…. two of us stepped forward!

No problem thinks the paymaster as he glances down at the pay slip and announces, “Wilson, Robert, William”

The both of us stood firm!

He then read out the 6 digit ID number, and we were separated by less than 100 numbers if memory serves (numbers are issued sequentially which just means we joined about the same time).

So, what are the odd of having identical names, and joining the air force within weeks of each other?

Below are the extended notes provided by Barbara Drescher for use in Skepticality Episode 200. Take a look and leave your comments below.

It’s not easy for me to put numbers on the probability of this happening because name frequencies in Australia were hard to find. However, I did find that the names “Robert” and “William” were as popular there in the 1960s (I assume that the author was between 17 and 25 when he joined) as the were in the U.S., where they took the 5th and 7th spots, respectively. As we’ve seen in past episodes, “Robert” is an enduring name; it was the #1 name for baby boys for decades and has not left the top 100 in more than a century. In the 1960s, “Robert” was the first name in 14,000 boys for every million born and “William” in every 10,000. There is no readily-available source to determine the probability that “William” would be chosen for a middle name, so the first name frequency will have to serve.

The surname name of “Wilson” is also a very common one, but it is difficult to determine just how common it was in Australia at that time. Today, “Wilson” is ranked 5th, occurring in 5,037.98 of every million people. This has probably changed a bit since the 1960s, but it’s our best estimate.
So, 140 of every million boys with the first name of “Robert” will have the last name of “Wilson”, and 1.4 of those will have the middle name “William”. This means that, for every 10 million men this author will meet around his age, 15 will probably share his full name.
The probability of joining the Air Force so close together adds a degree of complexity and to do it justice would require more accurate information about the distributions of these names across ethnic groups and as well as the distribution of ethnic groups in the military. Without that information, my best guess is the probability that another man in a selection of 100 will have this name, given that the author does, which is about 1 in a million.

## A Discovery of Friends

(Submitted by friend of the blog, Derek Colanduno)

So, I used to live in Las Vegas when I was a kid. My best friend Tony’s father was a test pilot for the Air Force out of Nellis Air Force Base.

One day, when I was at his house, some important military people showed up at his door to tell the family that his father had died while testing a new fighter jet. Tony later became the lead pilot for the Thunderbirds air squadron.

Fast forward to my life now; I have been good friends with astronomer Phil Plait since about 2005. Phil was able to get a pilot TV Show run on the Discovery Network for his program, “Bad Universe”. I was watching the second episode and in part of the episode Phil went to Nellis Air Force Base in Las Vegas to be in the passenger seat of a fighter jet to show the effects of G-force on the human body. The video cuts to Phil standing near the fighter jet and I get to see a pilot coming out to greet him on the tarmac.

Across the bottom of the screen, “Tony Mulhare”. So, here is one of my newest good friends getting to meet my oldest friend on national television no less.

And, to make it ‘funny’ it centered around Las Vegas, of all places!

[EDITOR: In case you never saw it, Bad Universe was a killer show with a short run. Think Mythbusters, with an astronomy theme and constant use of the phrase, “Holy Haleakala!”]