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Integration of third-party SDKs are essential in the development of mobile apps. However, the rise of in-app privacy threat against mobile SDKs — called cross-library data harvesting (XLDH), targets social media/platform SDKs (called social SDKs) that handles rich user data. Given the widespread integration of social SDKs in mobile apps, XLDH presents a significant privacy risk, as well as raising pressing concerns regarding legal compliance for app developers, social media/platform stakeholders, and policymakers. The emerging XLDH threat, coupled with the increasing demand for privacy and compliance in line with societal expectations, introduces unique challenges that cannot be addressed by existing protection methods against privacy threats or malicious code on mobile platforms. In response to the XLDH threats, in our study, we generalize and define the concept of privacypreserving social SDKs and their in-app usage, characterize fundamental challenges for combating the XLDH threat and ensuring privacy in design and utilization of social SDKs. We introduce a practical, clean-slate design and end-to-end systems, called PESP, to facilitate privacy-preserving social SDKs. Our thorough evaluation demonstrates its satisfactory effectiveness, performance overhead and practicability for widespread adoption. 

Many computational models of reasoning rely on explicit relation representations to account for human cognitive capacities such as analogical reasoning. Relational luring, a phenomenon observed in recognition memory, has been interpreted as evidence that explicit relation representations also impact episodic memory; however, this assumption has not been rigorously assessed by computational modeling. We implemented an established model of recognition memory, the Generalized Context Model (GCM), as a framework for simulating human performance on an old/new recognition task that elicits relational luring. Within this basic theoretical framework, we compared representations based on explicit relations, lexical semantics (i.e., individual word meanings), and a combination of the two. We compared the same alternative representations as predictors of accuracy in solving explicit verbal analogies. In accord with previous work, we found that explicit relation representations are necessary for modeling analogical reasoning. In contrast, preliminary simulations incorporating model parameters optimized to fit human data reproduce relational luring using any of the alternative representations, including one based on non-relational lexical semantics. Further work on model comparisons is needed to examine the contributions of lexical semantics and relations on the luring effect in recognition memory. 

We see the external world as consisting not only of objects and their parts, but also of relations that hold between them. Visual analogy, which depends on similarities between relations, provides a clear example of how perception supports reasoning. Here we report an experiment in which we quantitatively measured the human ability to find analogical mappings between parts of different objects, where the objects to be compared were drawn either from the same category (e.g., images of two mammals, such as a dog and a horse), or from two dissimilar categories (e.g., a chair image mapped to a cat image). Humans showed systematic mapping patterns, but with greater variability in mapping responses when objects were drawn from dissimilar categories. We simulated the human response of analogical mapping using a computational model of mapping between 3D objects, visiPAM (visual Probabilistic Analogical Mapping). VisiPAM takes point-cloud representations of two 3D objects as inputs, and outputs the mapping between analogous parts of the two objects. VisiPAM consists of a visual module that constructs structural representations of individual objects, and a reasoning module that identifies a probabilistic mapping between parts of the two 3D objects. Model simulations not only capture the qualitative pattern of human mapping performance cross conditions, but also approach human-level reliability in solving visual analogy problems.