On the one hand, it can be very convenient to get a coupon emailed to you based on your obsession with tacos. On the other, having every website you visit blast your eyes with ads for the same darn pair of lime green shoes you already bought as part of a Halloween costume and never intend to buy again. But some retailers say they’re working on tailoring such marketing efforts down to each person individually, to maximize effectiveness and cut down on irritation.

Whittling down the audience to each customer in order to find out not only what they’ve already bought and sell them something similar, retailers are now trying to get down to the individual and make sure they’re also offered different kinds of products, or to get them into physical stores based on online browsing habits, notes Sarah Halzack of the Washington Post.

Retailers from CVS to Barneys New York are going after shoppers with personalized pitches, studying which sites customers visit as well as whether or not they’ve opened or clicked through emails, checked out a company blog post or used a certain kind of coupon.

“For one million users, we want to have one million different site experiences,” Matthew Woolsey, Barneys’s executive vice president for digital told the Post.

As such, Barneys’ new Web site features personalized content that stems from data culled from both a shopper’s in-store purchases as well as how they surf for stuff online. So for example, a woman who browses online for fine jewelry might wait to buy it in-person. A retailer might think however, that just because she browsed and didn’t buy, she might not come into a store.

But by studying behavior across channels, Barneys says it’s learned the value in continuing to keep up the online marketing efforts, instead of switching to a new tactic.

There’s also the creepy factor — retailers are learning that shoppers often don’t like sharing data with retailers, but are okay with it when it generates obvious value for them. You give your location data to Google Maps, Halzack notes, because in exchange you get information that helps you get where you’re going.

It’s a fine line, but one that retailers are trying to walk, with varying success. Again, please don’t spray ads of something we’ve already bought across every single site we visit, because then it feels like being stalked by an insistent fan obsessed with that one time you actually did want lime green shoes.

Instead, figuring out what customers don’t have and might want is the key. That’s what CVS is working on, the company’s vice president of customer relationship management told the Post. Haven’t bought mascara lately? No trips to the store for aspirin? Could be time to stock up — here’s a coupon.

“Sometimes they may not realize we carry some of their other favorite items or that we may have a special that week on a type of product they would normally pick up elsewhere,” she explains.

Retailers are tailoring their Web sites and promotions for you. Just you. [Washington Post]

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