In a comment on last week’s twin names post, Erin said she’d “love to see some kind of analysis on what percentage of twins are given names that are/aren’t matchy-matchy.”
I do know of one analysis like this. It’s 50 years old, so it’s not exactly up-to-date, but these were the findings:
- 79% of twins overall had similar names
- 90% of identical twins had similar names
- 75% of fraternal twins had similar names
Name researcher Robert Plank published “Names of Twins” in the journal Names way back in 1964. This study was mentioned by H. Edward Deluzain in the essay “Names and Personal Identity” in 1996:
Robert Plank, who studied names of twins, discovered that the names fit into three patterns and that the names in two of the patterns show unmistakable similarity. The most common pattern, which occurred in 62% of the cases Plank studied, was the use of names that begin with the same letter. This included such names as Richard and Robert (Ricky and Robby), Joseph and Judith (Joey and Judy), Louise and Louisa, as well as such names as Paul and Paula and Patrick and Patricia. The second pattern involved names that had different first letters but where similar in sound, rhythm, or rhyme. Such sets of names as Tracy and Stacy, Billy Joe and Penny Sue accounted for 17% of the sets of names. Finally, Plank found that only 21% of the sets of names were different enough from one another to be considered dissimilar. Identical twins, who are always of the same sex and who look so much alike people have trouble telling them apart, fare worse than fraternal twins in the similarity of their names. For, as Plank found, almost 90% of the identical twins had similar names compared to roughly only 75% of the fraternals.
Have any of you seen more recent research on similar/dissimilar names for twins?