We're designing stuff, we look not necessarily just about what any given users going to experience，but what's going to be better for the whole coummunity and the whole product. And I mean, it's gonna be a lot of trade-off going all over the place in a product. Probably the most that you see every day is that you can't see the profiles of people at other schools. That's a really a major trade-off in the application.
For those of you who aren't familiar with this, we spilt up the user base by what school they go to and we make it so that people at a given school can only see the profiles and contact information of people at their school. And the reason for this was mostly to, because we realized that the people around you, at your school, are the people who you want to look at mostly anyway. And if we made the space too broad and let anyone see your information. then that probably fine. I mean, look up some people, but you also probably won't put up your cellphone.
More than a third of people on Facebook have their cellphone up there, and that's something that's something useful for the application. So in designing it, this was a trade-off that we made. I kind of thought of what was wrong. I said, well, what would be more useful? Would it be better for people to be able to see everyone and maybe not feel like this is a secure environment in which they can share their interests and what they thought and what they care about? Or would be better that more information and more expression was available, but to a smaller audience which is probably the relevant audience for any person? So, there are a lot of decisions like that, that are getting made and a lot of them are gut level.
超过三成的Facebook用户在注册时登记过电话号码，所以对我们这个应用是很重要的。所以在设计产品的时候就要做这种取舍.我觉得这样做好像不对，一 直在想什么会更有用?要么将用户信息对所有人开放，但这却让人们觉得在这样的网络中分享自己的所感所想不太安全还是仅将更多的用户信息和状态展示给少部分 与该用户有关的人。我要做很多类似的决定，而且这些决定是要靠直觉判断的。
So i mean, we tried to be as academic about this possible in trying to think rigorously through the different results that we'll get if we go to different directions. But a lot of it is just like you define your objectives, what you're going for. In this case, to optimize for the best of the whole community and the whole user base and over the long term, and that's important too, long term but short term. And then, you just kind of operate and do what you think will be best along that line.