This paper presents a study of obfuscation practices in location-sharing systems. The study shows that users have relatively complex preferences that depend on the recipient of the location, the time of the request and location. The preferences also require multiple levels of obfuscation (ranging from disclosing no location information to disclosing the exact location) to accurately capture. Fo...

This paper presents a study of obfuscation practices in location-sharing systems. The study shows that users have relatively complex preferences that depend on the recipient of the location, the time of the request and location. The preferences also require multiple levels of obfuscation (ranging from disclosing no location information to disclosing the exact location) to accurately capture. Fo...

In the cryptographic currency Bitcoin, all transactions are recorded in the blockchain — a public, global, and immutable ledger. Because transactions are public, Bitcoin and its users employ obfuscation to maintain a degree of financial privacy. Critically, and in contrast to typical uses of obfuscation, in Bitcoin obfuscation is not aimed against the system designer but is instead enabled by d...

This paper motivates and explores an expressivist theory of vagueness, modeled on Allan Gibbard’s (2003) normative expressivism. It shows how Chris Kennedy’s (2007) semantics for gradable adjectives can be adjusted to fit into a theory on Gibbardian lines, where assertions constrain not just possible worlds but plans for action. Vagueness, on this account, is literally indecision about where to...

The relation of similarity is essential in understanding and developing frameworks for reasoning with vague and approximate concepts. There is a wide spectrum of choice as to what properties we associate with similarity and such choices determine the nature of vague and approximate concepts defined in terms of these relations. Additionally, robotic systems naturally have to deal with vague and ...

There are many examples in the literature that suggest that indistinguishability is intransitive, despite the fact that the indistinguishability relation is typically taken to be an equivalence relation (and thus transitive). It is shown that if the uncertainty perception and the question of when an agent reports that two things are indistinguishable are both carefully modeled, the problems dis...