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orijing

1,359 karma · joined January 26, 2011

BS/BS/BA from UC Berkeley for EECS, business administration and economics. Software engineer at Facebook.
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orijing··on Facebook e-mail mess: Address books altered, e-mail lost
Can you elaborate on why you think in this specific case user privacy or security conflict with Facebook's goals?
orijing··on Where has all the money in the world gone?
Here is an answer from Quora that really resonated with me: http://www.quora.com/In-recent-days-trillions-of-dollars-of-...

Basically, these wealth were expectations.

orijing··on What Facebook Knows
While I agree with 2, I'm not convinced by 1--where can you get data that is unbiased without FORCING random sets of people to participate in a study in the way you want them to? Even FDA-mandated experiments are biased by the fact that it requires volunteers.
orijing··on Lawyer attacking The Oatmeal shocked by big mean Internet’s reaction
Did you mean AP? (Accounts Payable)
orijing··on Folly - The Faceboook open source library
What is "low-fragmentation heap"? Why would anyone want "high-fragmentation heap"? (since you imply that it's an option)
orijing··on Software Raises Bar for Hiring
Wait, I'm confused... Are you saying that it can be illegal to have hiring practices that are suboptimal? For example, you mention that brain-teaser tests might have disparate impact on some applicants--and they're also not that effective anyway.
orijing··on Germany sets new solar-power record
I don't disagree that the US government should and tries to do what's best for itself (to the extent possible within the constructs of the political system...).

I'm just saying that I believe it's not in its interests ultimately to levy such a heavy tariff on solar panels, regardless of where they're from. You may disagree on this, as many will disagree with China's policies.

I'd love to get cheap, subsidized solar panels--better if it's not subsidized by my own taxes. I just think levying a punitive tariff goes against even the spirit of self interest.

orijing··on Germany sets new solar-power record
That depends on whose perspective you're looking from. From the US solar manufacturer's perspective, of course it's not a bad thing, since it stifles competition.

But from the perspective of people in the US who want solar panels, or Chinese producers of solar panels, it definitely is a bad thing.

Also, the link you supplied doesn't mention a word about solar--so punishing solar companies in order to "get back at" wind companies just doesn't make sense. Moreover, it isn't the case anymore that the Yuan is unambiguously undervalued. Many things are more expensive in China (in exchange-weighted nominal terms) than in the US, such as cars, electronics, etc. Also, in terms of the current account surplus, it is considered "normal" now [1].

[1] http://www.economist.com/node/21553041

orijing··on Germany sets new solar-power record
That's true. I just think of kilowatt-hours as a single unit, like Joule. That way it's no more bizarre than saying Newtons instead of kg m/s^2
orijing··on Germany sets new solar-power record
That's a great question. Take the US as an example, since it has plenty of sunshine.

Nowadays investment in renewable energies is politically risky after the Solyndra failure, after the DOE gave Solyndra over half a billion dollars of loan guarantees.

After the dramatic failure of its own renewable energy initiative, it began attacking other countries' initiatives to expand solar use. For example: "The U.S. yesterday imposed tariffs of as much as 250 percent on Chinese-made solar cells to aid domestic manufacturers beset by foreign competition, though critics said the decision may end up raising prices and hurting the U.S. renewable energy industry." [1]

It's a sad state when the US government--presiding over one of the sunniest and advanced nations in the world--will not only refuse to sponsor domestic initiatives to bolster renewable energy development, but also punish countries that do.

[1] http://www.dailykos.com/story/2012/05/18/1092726/-250-Tariff...

orijing··on Yelp, You Cost Me $2000 by Suppressing Genuine Reviews. Here’s How You Fix It
That made me think of an interesting idea. No problem is not solvable with some level of indirection!

A review aggregator website where the value of reviews from various sources is weighted by how reliable they are. For example, if there is Yelp, Facebook and Google, it can weight a restaurant 0.7 Yelp, 0.2 Facebook and 0.1 Google.

orijing··on Amazon Low Prices Disguise a High Cost
Just curious, isn't selling below cost called "dumping" and is illegal in many places?
orijing··on The effect of Groupon promotions on Yelp ratings
It's true that the average clearly moved, but the author was trying to make a generalized inference from the average, that there was a structural break in the "true average" insofar as the measured average is just a sample/noisy measurement of the "true average". Therefore, error bars/confidence bars would indicate how likely the structural break in measured outcomes is to reflect a structural break in the underlying "true average."

The volatility/variance comes from the fact that 1. not everyone rates their experience, 2. there's variability in the experience, 3. different people have different expectations or likelihood to rate high/low, etc.

I hope that clarified what I believe was the parent's meaning.

orijing··on Stallman: "Facebook is an international parasitism project."
Imagine it this way. Your friends are data, you have limited capacity, and you access them with some pattern. Suppose you live in a world without Facebook.

Your wife and kids are in your registers. You see them all the time, and generally they're either a room away or (at the most) a phone call away.

Your best friends are in your L1 cache. Sometimes they come up to the registers after you've been hanging out with them for a while, but even if not, they're only a phone call or text away in the L1 cache.

...

Your friend from elementary school you haven't talked to for years is on disk swap. He lives in Japan, and you might want to contact him if you're traveling there.

In that world, it's still very cheap to access your most frequently-accessed connections--your wife, kids, best friends. However, as you go down the memory hierarchy it becomes very expensive to access them. And so, you contact them less often.

Enter Facebook. Now your friend from Japan is only a post away. You don't have time to have email threads with all of your friends, down to that friend from elementary school. But you can occasionally keep up with that friend by browsing to his timeline, occasionally seeing some major events "X got engaged", and maybe sending a light message. Suddenly your disk became an SSD and it became much cheaper to keep in contact.

Your registers and L1 caches haven't changed much. Now you can contact them in the medium that's most convenient at the time. You can message them from your phone (fb messenger), or skype them on your computer, but you can also just call them or talk to them. Facebook gives you more options for accessing the most-accessed friends. As a result, it both expands the size of your caches and main memory, but also makes each level faster to access so you can keep in touch with more of them.

So I don't think the right approach is to think of friends in a binary fashion: Worth keeping in touch with, and not worth keeping in touch with.

Instead, it's a gradient, and communication platforms like Facebook just improve the gradient so it's worthwhile (i.e. possible and easy) to keep in touch with a lot more of your friends.

orijing··on Don’t Be Evil: How Google Screwed a Startup
I have a question about what happens when an account gets disabled/suspended while there's a positive balance. Does Google keep that surplus, or return it to advertisers? If the former, that's truly evil, so let's say the latter.

If they return to advertisers, would they suddenly see a drop in their budget spent, and number of clicks produced? For example, say I have an AdWords account and yesterday I owe Google $100 for 100 clicks, and today someone who had a balance from my ads got suspended, and they generated 2 clicks at $1 each. Does my bill go down to $98, and clicks to 98? If so, that's pretty weird.

Does anyone who has an AdWords account know?

orijing··on OMGPOP Draws Zynga’s Daily User Traffic Up By 25%
If it really made 200k a day on ads, that's 73 million a year. That would be crazy if true and would justify a 200m valuation.
orijing··on What you could do if you were Google and had their databases
The interesting thing is that Google itself has an internal hedge fund (or something close) that trades its cash hoard. I'm not sure if they do it algorithmically or whether they just buy-and-hold various indices, but my suspicion is that (given their engineering background) they probably do some algorithmic trading.
orijing··on JPMorgan Sees Clients With Less Than $100,000 Unprofitable
4. is one of the points that's being addressed by the amendment you're mentioning. In particular, it'll limit the fees that can be charged for things like debit cards, checking accounts, etc--the fees that made unprofitable customers profitable.
orijing··on Best Practices for Speeding Up Your Web Site
Not to be a troll but how much of that is patented by Yahoo? If its recent threat to sue Facebook is any indication, "Methods to reduce HTTP requests" could be one of its patents that it's willing to wield.
orijing··on Steve Jobs ignored Warren Buffett's advice for a stock buyback
Interesting man!

What I wonder about is how banking fees impacted his ability to issue/buy back shares. For example, secondaries handled by an investment bank cost a fraction of the issue. So his shares must have been significantly under and over valued in order for his buying/selling to be profitable.

orijing··on Facebook Starts Turning Listen, Read, and Watch Stories Into Ads
Yup! That's the magic of open graph.

I am an engineer on facebook's ads team.

orijing··on The Real Problem with Facebook's Timeline
That would be a great app--Facebook content management utility. Write a few queries, like the UI equivalent of

  UPDATE posts SET visibility = CLOSE_FRIENDS WHERE ts < NOW() - 3600 * 24 * 365

  DELETE FROM posts p WHERE COUNT(SELECT id FROM tags t WHERE t.post_id = p.post_id AND t.user_id = EX_GIRLFRIEND_ID)=1
orijing··on CityHash: new hash function by Google (faster than Murmur)
That's not the definition of a cryptographic hash. One of the four requirements of a function being a cryptographic hash function is that "it is infeasible to find two different messages with the same hash."
orijing··on Killing the Competition: How the New Monopolies Are Destroying Open Markets
It's up to each company's interview process to weed out the people who aren't likely to add value. Offering more would simply increase the company's available pool of employees. Put another way, the set of people who would work for you at $x is a subset (generally) of the set of people who would work for you at $y > $x
orijing··on Killing the Competition: How the New Monopolies Are Destroying Open Markets
Demand is only outstripping supply because they aren't paying sufficiently. That's the essence of the market. If they would only pay more, then demand would certainly not outstrip supply.
orijing··on Facebook Timeline is too awful to be an accident
> Timeline also makes branded posts (ads) look nearly identical to the actual content we’re on facebook to see, so it follows that they’d be processed similarly.

I'm not sure what the author is referring to, but the ads on the side (regrettably IMO) look nothing like the organic content in the main Timeline columns. There isn't enough space to show more organic content on the side as there is next to the Newsfeed. Why does the OP think that the ads are "nearly identical" to organic content?

orijing··on No New Accounts Today
What is the daily variance like?
orijing··on Google, what were you thinking?
They are also a public company that generates profits for shareholders.
orijing··on Google's Kenyan ripoff?
Here's the original post: http://blog.mocality.co.ke/2012/01/13/google-what-were-you-t...
orijing··on Why Google And Facebook Need To Go Dark To Protest SOPA
I'm not trying to troll but is Google much better for that query than Bing? Or is it lack of awareness of Bing?
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