I haven't thought about this problem extensively, but it seems you could maintain anonymity by hiding results for segments with a small number of responses. That's basically what this is doing, except the "segments" are user-defined and private.
If I'm the only one at my company who has responded then a search for my company won't turn up anything. If a dozen other people have then it will. If only one of those has the same job title then it if I search for my company and my job title nothing will show up. If 8 have the same job title then they will show up. Restricting it to one "axis" might solve that but the data would be less interesting.
Of course you have to be careful since certain combinations of searches could also reveal information (kind of like those logic questions: Sally is taller than Bob, Bob is shorter than Joe, etc, etc. Who is tallest?)
Excluding the company name and restricting location searches to large enough regions would remove a lot of the risk. It would be cool to be able to ask questions like "What are the salaries of software engineers with 5 years experience in Silicon Valley?" or "How much does having a BS degree increase your salary? MS degree? PhD?" or "How do salaries scale with # years experience?"
If I'm the only one at my company who has responded then a search for my company won't turn up anything. If a dozen other people have then it will. If only one of those has the same job title then it if I search for my company and my job title nothing will show up. If 8 have the same job title then they will show up. Restricting it to one "axis" might solve that but the data would be less interesting.
Of course you have to be careful since certain combinations of searches could also reveal information (kind of like those logic questions: Sally is taller than Bob, Bob is shorter than Joe, etc, etc. Who is tallest?)
Excluding the company name and restricting location searches to large enough regions would remove a lot of the risk. It would be cool to be able to ask questions like "What are the salaries of software engineers with 5 years experience in Silicon Valley?" or "How much does having a BS degree increase your salary? MS degree? PhD?" or "How do salaries scale with # years experience?"