k-anonymous Microdata Release via Post Randomisation Method

The problem of the release of anonymized microdata is an important topic in the fields of statistical disclosure control (SDC) and privacy preserving data publishing (PPDP), and yet it remains sufficiently unsolved. In these research fields, k-anonymity has been widely studied as an anonymity notion for mainly deterministic anonymization algorithms, and some probabilistic relaxations have been developed. However, they are not sufficient due to their limitations, i.e., being weaker than the original k-anonymity or requiring strong parametric assumptions. First we propose Pk-anonymity, a new probabilistic k-anonymity, and prove that Pk-anonymity is a mathematical extension of k-anonymity rather than a relaxation. Furthermore, Pk-anonymity requires no parametric assumptions. This property has a significant meaning in the viewpoint that it enables us to compare privacy levels of probabilistic microdata release algorithms with deterministic ones. Second, we apply Pk-anonymity to the post randomization method (PRAM), which is an SDC algorithm based on randomization. PRAM is proven to satisfy Pk-anonymity in a controlled way, i.e, one can control PRAM's parameter so that Pk-anonymity is satisfied. On the other hand, PRAM is also known to satisfy ${\varepsilon}$-differential privacy, a recent popular and strong privacy notion. This fact means that our results significantly enhance PRAM since it implies the satisfaction of both important notions: k-anonymity and ${\varepsilon}$-differential privacy.Comment: 22 pages, 4 figure

The ACT Report: Action to Catalyze Tech, A Paradigm Shift for DEI

Despite widespread awareness of the lack of DEI in tech and public commitments from tech companies to do better, great uncertainty exists among leaders about how to make real progress.While there are deep pockets of DEI excellence within tech companies themselves, there has never been an attempt to connect this knowledge in a one-stop shop for people and leaders working across tech, nor has there been an effort to catalyze DEI outcomes through collaborative industry-wide action. DEI can't be solved by one company or leader; it requires long-term collective effort.The ACT Report calls for a new paradigm in DEI that is holistic, collective, and long-term. Tech's current approach is often dispersed, individual, and short-term. Despite important progress in DEI, tech companies are too often reduced to poaching each other's talent from underrepresented groups. The paradigm shift described in the ACT Report fundamentally requires a shift in thought and behavior. It is based on values, and provides a blueprint to indivisibly link DEI strategy and business strategy. Companies must bring a business approach to inclusion, and an inclusive approach to business. In other words, DEI and business strategies can no longer be separate. The ACT Report explains what this means in practice.Making the tech industry more inclusive requires a systemic response to a systemic problem. The foundational system that impacts employment opportunity is education. The tech industry, like other industries, must deliver early intervention measures at scale to drive equity from cradle to career. That means tackling educational inequity generally, and increasing access to computer science education specifically.

The Role of Peer Influence in Churn in Wireless Networks

Subscriber churn remains a top challenge for wireless carriers. These carriers need to understand the determinants of churn to confidently apply effective retention strategies to ensure their profitability and growth. In this paper, we look at the effect of peer influence on churn and we try to disentangle it from other effects that drive simultaneous churn across friends but that do not relate to peer influence. We analyze a random sample of roughly 10 thousand subscribers from large dataset from a major wireless carrier over a period of 10 months. We apply survival models and generalized propensity score to identify the role of peer influence. We show that the propensity to churn increases when friends do and that it increases more when many strong friends churn. Therefore, our results suggest that churn managers should consider strategies aimed at preventing group churn. We also show that survival models fail to disentangle homophily from peer influence over-estimating the effect of peer influence.Comment: Accepted in Seventh ASE International Conference on Social Computing (Socialcom 2014), Best Paper Award Winne

A vision for global privacy bridges: Technical and legal measures for international data markets

From the early days of the information economy, personal data has been its most valuable asset. Despite data protection laws and an acknowledged right to privacy, trading personal information has become a business equated with "trading oil". Most of this business is done without the knowledge and active informed consent of the people. But as data breaches and abuses are made public through the media, consumers react. They become irritated about companies' data handling practices, lose trust, exercise political pressure and start to protect their privacy with the help of technical tools. As a result, companies' Internet business models that are based on personal data are unsettled. An open conflict is arising between business demands for data and a desire for privacy. As of 2015 no true answer is in sight of how to resolve this conflict. Technologists, economists and regulators are struggling to develop technical solutions and policies that meet businesses' demand for more data while still maintaining privacy. Yet, most of the proposed solutions fail to account for market complexity and provide no pathway to technological and legal implementation. They lack a bigger vision for data use and privacy. To break this vicious cycle, we propose and test such a vision of a personal information market with privacy. We accumulate technical and legal measures that have been proposed by technical and legal scholars over the past two decades. And out of this existing knowledge, we compose something new: a four-space market model for personal data

Group membership and staff turnover affect outcomes in group CBT for persistent pain

The effects of two contextual factors, group membership and staff turnover, on the outcome of group cognitive behavioral therapy (CBT) for persistent pain were investigated. The data came from end of treatment and one month follow-up assessments of 3050 individuals who attended an intensive group programme over sixteen years. Intraclass correlations (ICC) showed significant intragroup effects on self-efficacy (ICC = 0.16 at end of treatment; 0.12 at one month), catastrophizing (ICC = 0.06; 0.13) and distance walked (ICC = 0.20; 0.19). This underlines the importance of modelling group membership when analyzing data from group interventions. Linear regression showed that high periods of staff turnover were significantly related to poorer outcomes on self-efficacy and distance walked at end of treatment, with the effect on self-efficacy persisting to one month follow-up. Having demonstrated significant contextual effects in an existing data set, further research is needed to explore the mechanisms by which these effects operate