SAN JOSE, Calif. – Nearly half of all Californians choose not to be listed in the phone book, putting the state third behind Nevada and Arizona in numbers of people who are intentionally difficult to reach.

“[Californians] just have this obsession with privacy,” said Linda B. Piekarski, the head of research at Survey Sampling International, a Connecticut-based polling company that provided the unlisted rates to the San Jose Mercury News.

“I like the freedom of giving my number to somebody and knowing that only they will call,” said Daniel Vasquez, an unlisted San Jose resident.

New England residents, by contrast, are an open book: 93 percent in Vermont are listed, 89 percent in Maine and 85 percent in New Hampshire.

Nationwide, slightly more than a third of Americans are unlisted.

Californians’ penchant for privacy could complicate the wireless industry’s plan to compile the nation’s first 411 directory of cell phone numbers. State lawmakers are trying to force the industry to get permission from consumers to divulge their mobile phone numbers.

According to pollsters, there’s no single explanation for California’s high numbers of people wishing to keep their numbers private.

One factor may be the cheaper cost of being unlisted: only 14 cents a month in California.

In Minnesota, where fewer than a third of households are unlisted, residents must pay $1.45 a month to maintain their privacy.

But price can’t explain everything: Nevada and Arizona charge about $2 a month and have higher unlisted rates than California.

“California is really the start-over state,” said Beth Givens, director of the Privacy Rights Clearinghouse in San Diego. “Maybe it’s people coming here to start life anew and not wanting to be found.”