Dear farhad

How Does Facebook Know I’m Gay?

Slate’s tech-advice column answers your questions about marketing on social networks, Gmail’s deletion policy, and more.

If you’ve got a tech problem you want solved, please send a note to farhad.manjoo@slate.com, with “I’ve got a tech question!” as the subject line. (Your question may be edited.)

Dear Farhad,
How does Facebook pick which ads to display? I’m gay, out, and proud, but my sexual orientation isn’t listed on my Facebook page. However, Atlantis’ gay-cruise ads still appear when I’m browsing. Has the site somehow figured out that I’m gay?

—Not Happy With Facebook Ads

Dear Not Happy,
According to a Facebook spokesman, you’ve most probably been swept up in an ad targeted to a very broad group. When companies advertise on Facebook, they’re allowed to choose a range of demographic characteristics that determine which people see their ads. It’s possible that Atlantis didn’t choose to limit its ads just to gay people but, say, to all single men under 40 who live near San Francisco. This way the company gets to people like you—folks who aren’t out on Facebook but who might still be in the gay-cruise demographic.

The Facebook rep added a couple other points: Ads aren’t selected based on groups you’ve joined or based on your friends. You weren’t shown the gay-cruise ad because your friends are gay or because you became a fan of the group “No on Prop 8,” for instance.

But there is one caveat: If a friend of yours presses “Like” on an ad, Facebook will show you the ad, too, plus a note saying which of your friends liked it. The company also uses the “Like” feature to determine which ads to show you in the future.

—Farhad

Dear Farhad,
When you delete an e-mail or any other document from a Google account, is it gone forever? I’ve been wondering about this as I’ve become an active user of Gmail, Google Docs, Google Voice, and Google Sites. Google recently provided e-mails to prosecutors looking to convict a Bear Stearns trader of malfeasance—even though the trader had shut down his Google account. I know that if I click “Delete,” I’ll never see my e-mail again. But will Google still have it—not to mention any government agency that comes knocking?

—Google Knows What I Did Last Summer

Dear Google Knows,
You’re right that Google doesn’t actually delete your e-mail when you click “Delete.” According to a spokeswoman, e-mail remains on Google’s servers for 60 days after you’ve trashed it. Other Google services have a similar lag. It takes up to 30 days for a deleted document to get off Google Docs, 60 days for a deleted picture to vanish from Picasa Web Albums, and 90 days for deleted voice mail to be freed from Google Voice. Google, like all Web companies, does comply with court orders to produce user information, though it also has a history of fighting egregious requests. In 2006, Google managed to get a court to limit significantly the scope of a Justice Department subpoena requesting two months’ worth of search data from Google users.

But to be on the safe side, you’d better delete anything that might be of interest to the government at least two months before they’re likely to get wind of it. Or keep evidence of your shady dealings in a USB drive under your mattress.

—Farhad

Dear Farhad,
Could you please find out why Gmail’s search function sucks so hard? It doesn’t do wild cards. It can’t handle misspellings. It can’t even present me both hyphenated and unhyphenated versions of the same word. The beauty of Google search is that, many times, it seems magically to know what I mean. With Gmail search I have to fight it like an old-school text-based adventure game. Why?

—Gmail Can’t Find What I’m Looking For

Dear Gmail Can’t Find,
Huh, is Gmail search really that bad? I have to confess I’ve never had that problem. All of the shortcomings you mention are true—it doesn’t do wild cards and can’t handle misspellings—but I don’t recall these limits ever keeping me from finding the e-mail I was after. What’s more, Gmail’s search is much faster than search on many desktop e-mail clients, especially when you overload those systems with tens of thousands of messages.

I think Google’s Web search engine has raised your expectations for all search boxes. As a Google spokeswoman pointed out when I called to ask about your problems, Gmail search will never be as magical as Google search. That’s because they’re two very different systems. Google search gets its intelligence from collective action; it knows what link to show you even when you’ve misspelled your query because lots of other people have done the same thing. Gmail search, on the other hand, is a silo. It can’t study collective intelligence and therefore can’t know that if you typed in “pubic school teacher,” you meant “public.” Here’s one tip, though: In April, Gmail unveiled Search Autocomplete, a feature that you can turn on in Gmail Labs. This will cut down on your misspellings—type in F-A-R-H and voila, you’ll see my e-mail come up in a drop-down list.

—Farhad

Dear Farhad,
Why don’t pop-up blockers work anymore? I’m a faithful Firefox user and pop-ups get through on nearly every site I visit. When I turn off Firefox’s pop-up blocker even more get through. I hate browser toolbars so what is the best solution for annoying pop-ups and Flash ads for Firefox?

—Annoyed By Pop-Ups

Dear Annoyed,
Web browsers’ built-in pop-up blockers work on a certain class of pop-ups. Advertisers are wise to this, and they’re always trying new ways to break through. One common method is to use pop-ups that rely on Adobe Flash, which browsers can’t easily block. If you’re using Firefox, the easy way to block these ads—as well as a whole range of others—is to use an add-on like Adblock Plus or Flashblock.

But if you’re seeing pop-ups on nearly every site you visit, it’s possible that these are coming from someplace else—spyware on your computer. I’d suggest running a spyware checker like Spybot Search & Destroy to look for malware on your machine.

—Farhad

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