Why is the letter J so common in names of people who go by their initials? [closed]

Solution 1:

The reason may be that J. usually stands for John.

In many (if not all) European countries, there is a tradition of using double first names, as in "John-Peter", "Jean-Marc", "Franz-Johann", "Jan Pieter", etc. Notice that hyphenation is immaterial. Variations of John are most probably the commonest element in male double first names; I know for a fact that they are in Dutch, and what evidence I have seems to point to this being the case in other languages too. Since double first names are the kind of first names that are most commonly initialized, being longer than simple first names, it follows that they will contain a disproportionate number of J's.

It makes sense when you think about it: the better known a word is, the more chance that it will be abbreviated. You would sooner abbreviate Mister as Mr than archaeopalaeontologist as ap. The Romans, for example, had a very limited number of first names:

In the early centuries of the Roman Republic, about three dozen praenomina seem to have been in general use at Rome, of which about half were common. This number gradually dwindled to about eighteen praenomina by the 1st century B.C., of which perhaps a dozen were common. — Wikipedia.

That is why it was possible to use one or two-letter abbreviations for most names without ambiguity. So Marcus was M., Publius P., Cnaeus Cn., etc.

Solution 2:

According to wikipedia the most common first names for males in the US according to the 1990 census are, in that order:

'James','John','Robert','Michael','William','David','Richard','Charles','Joseph', and 'Thomas'

Let's use an approximate probability distribution (any better way?) that gives the probabilities to these names according to their order i (starting at 0) following:

P(name_i) = 0.15 / (i + 2)

This is a probability distribution for at least 1000 names (sums to 1), and starts like this:

0.0749, 0.0499, 0.0374, 0.0299, 0.0249, ...

meaning that someone has 7.49% chances of being called James. The sum of the probabilities of having a name starting with J from these list is 14% (P(James)+P(John)+P(Joseph)), lets call it Pj. Of course Pj is in fact higher because more names than these 8 in the list of 1000 may start with J.

Now let's assume a child is given three first names, the probability that at least of them starts with J given pj is 36%!! (from (1-(1-pj)^3)). So every time you meet a new person, you have one third chances to see him having a J on his business card... that's huge. Let's call this probability pIJ, probability of at least one initial starting with a J.

However, when you say overwhelming majority, let's assume that you mean 8 out of 10. The probability that out of 10 people you meet in a row 8 have a name starting with a J is, using binomial distribution, only 0.5% I'm afraid, by comb(10,8)pIj^8(1-pIj)^2 .

However, if you settle with 5 our of 10, your chances rise to 16%.

Please someone correct me if the math is wrong.

Solution 3:

Maybe because the "Jay" sound could be someone's name and therefore sounds relatively natural.

Hi (e)M, Hi J(ay). "M" sounds strange, and is not likely to catch on. Whereas, I might actually think the guy's name is "Jay", not "Jack".

K(ay) might work the same way. (Except, men normally don't want to be known as "K".) And women may be too new to this game to have yet made a serious impact in terms of frequency of use.

The police use the same effect in naming their canine divisions - "K9".

I'm sure marketers and others would love to study this phenomenon.