So Antonella is joined by Natasha, Ashley, Kristen and other characters from Ford’s imagination, each depicted in a Dewar’s profile type of write-up, and with images grabbed from the Internet. Antonella has her male counterpart in Anton. Jack is the presiding personality for the 2010 Taurus. Joe and Cal are the ideal characters for future trucks.

Antonella cares more about the design and function of her telephone than that of her car. Her priorities in the Fiesta are visible in the car’s central panel, where controls inspired by those of a cellphone operate the audio and air-conditioning systems. Designers working on the Fiesta referred to the shape framing the dashboard instruments as “Antonella’s glasses.”

Ford’s goal in using made-up characters is that they will help produce cars that transcend national traits and are instead built around international, psychological archetypes. Antonella is an extreme version of a type the Ford designers call the fun-seeker.

“There are fun-seekers in London and Cleveland,” Mr. Callum said.

But the image of the fun-seeker appears sharply etched and more extreme when set in Rome. “In Rome there are lots of small cars,” Mr. Yalman said. “They are always dodging each other. So a car there has to be nimble and it has to look the part. Romans have been conscious of how their vehicles look  all the way back to Caesar. Every little crease of their toga has to be just right.”

Mr. Yalman first found the composite characters useful when he began directing marketing efforts for Ford in Europe. Confronted with many boundaries of nation and language, he said, he looked instead at common values and attitudes, a process he referred to as mindset segmentation. “We did a value and attitude map,” he said.

Mr. Yalman found that archetypes like Antonella, the type he called hedonistic, existed in all countries.