How many of your Facebook friends or Instagram followers do you really know?

If you're one of the many New Jerseyans who post on social media about their upcoming vacations, or update their page with photos and "check-ins" as the trip progresses, the answer better be "all of them."

"We don't want our residents going off and advertising when their houses are empty or vacant," said Capt. Fred Reck with the Marlboro Twp. Police Department. "There's obviously a difference between social media friends and our close personal friends and family. It's important for residents to know the difference between the two."

Reck is responding to a new survey that shows more than a third of New Jerseyans (37 percent) publicly announce on social media where and when they are going on vacation, or post on social media when they're away.

According to Security Baron, which conducted the nationwide survey, this practice is a burglar's dream. A significant proportion of vacationers unknowingly put their homes at risk by advertising to the world that they are not at home, the site said.

And the site says "unknowingly" because the survey results suggest it. More than half of respondents said they don't worry about the security of their home while on vacation. It hadn't occurred to 40 percent of respondents that posting photos while on vacation might be a security risk.

According to the survey, a quarter of residents "feel a social pressure" to post vacation updates.

Joel Penney, associate professor with the School of Communication and Media at Montclair State University, said attitudes towards privacy have shifted, especially among the younger generation, in the face of social media.

"It has created social norms around publicity as opposed to privacy," he said.

Despite any risks involved, Penney said, individuals who post about their upcoming trips, or during them, are not always doing so just to brag.

"I think there's also a component of wanting to share an experience and wanting to delight your friends," Penney said.

Capt. Reck advises residents to post all pictures and stories after returning home from vacation. If you can't resist, at least get a neighbor to keep an eye on your home while you're gone.

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