Secret Key Agreement under Discussion Rate Constraints

For the multiterminal secret key agreement problem, new single-letter lower bounds are obtained on the public discussion rate required to achieve any given secret key rate below the secrecy capacity. The results apply to general source model without helpers or wiretapper's side information but can be strengthened for hypergraphical sources. In particular, for the pairwise independent network, the results give rise to a complete characterization of the maximum secret key rate achievable under a constraint on the total discussion rate

On the Optimality of Secret Key Agreement via Omniscience

For the multiterminal secret key agreement problem under a private source model, it is known that the maximum key rate, i.e., the secrecy capacity, can be achieved through communication for omniscience, but the omniscience strategy can be strictly suboptimal in terms of minimizing the public discussion rate. While a single-letter characterization is not known for the minimum discussion rate needed for achieving the secrecy capacity, we derive single-letter lower and upper bounds that yield some simple conditions for omniscience to be discussion-rate optimal. These conditions turn out to be enough to deduce the optimality of omniscience for a large class of sources including the hypergraphical sources. Through conjectures and examples, we explore other source models to which our methods do not easily extend

Duality between Feature Selection and Data Clustering

The feature-selection problem is formulated from an information-theoretic perspective. We show that the problem can be efficiently solved by an extension of the recently proposed info-clustering paradigm. This reveals the fundamental duality between feature selection and data clustering,which is a consequence of the more general duality between the principal partition and the principal lattice of partitions in combinatorial optimization

Generalized Group Testing

In the problem of classical group testing one aims to identify a small subset (of size $d$) diseased individuals/defective items in a large population (of size $n$). This process is based on a minimal number of suitably-designed group tests on subsets of items, where the test outcome is positive iff the given test contains at least one defective item. Motivated by physical considerations, we consider a generalized setting that includes as special cases multiple other group-testing-like models in the literature. In our setting, which subsumes as special cases a variety of noiseless and noisy group-testing models in the literature, the test outcome is positive with probability $f(x)$, where $x$ is the number of defectives tested in a pool, and $f(\cdot)$ is an arbitrary monotonically increasing (stochastic) test function. Our main contributions are as follows. 1. We present a non-adaptive scheme that with probability $1-\varepsilon$ identifies all defective items. Our scheme requires at most ${\cal O}( H(f) d\log\left(\frac{n}{\varepsilon}\right))$ tests, where $H(f)$ is a suitably defined "sensitivity parameter" of $f(\cdot)$, and is never larger than ${\cal O}\left(d^{1+o(1)}\right)$, but may be substantially smaller for many $f(\cdot)$. 2. We argue that any testing scheme (including adaptive schemes) needs at least $\Omega \left((1-\varepsilon)h(f) d\log\left(\frac n d\right)\right)$ tests to ensure reliable recovery. Here $h(f) \geq 1$ is a suitably defined "concentration parameter" of $f(\cdot)$. 3. We prove that $\frac{H(f)}{h(f)}\in\Theta(1)$ for a variety of sparse-recovery group-testing models in the literature, and $\frac {H(f)} {h(f)} \in {\cal O}\left(d^{1+o(1)}\right)$ for any other test function

Maternal neonaticide, shame and social melancholy in Hsu-Ming Teo’s love and vertigo

Most critics read Love and Vertigo (2000) by Chinese-Australian writer Hsu-Ming Teo as a novel about diaspora and migrancy. However, the recurrent trope of maternal neonaticide has been critically neglected considering Teo’s portrayal of the predicaments of two generations of mothers who either dispose of or kill their neonates. This article refutes the cultural and radical feminists’ reductionist essentialization of maternal morality depicted in most literary works by probing into the ambivalence in motherhood represented by maternal neonaticide in the selected novel. Drawing on Kelly Oliver’s theory of social melancholy, this article critically examines motherhood against the specific sociohistorical context, aiming to deconstruct the stigma and pathology surrounding maternal neonaticide. Oliver proposes that social melancholy stems from one’s inability to mourn the lost lovable self due to the unavailability of positive representation of motherhood in the phallocentric society. Traditional maternal ethics tend to stigmatize or pathologize mothers who kill, which covers up the institutional causes for maternal neonaticide as a symptom of social melancholy. This article interprets maternal neonaticide as a manifestation of what has been suppressed by the hierarchical and phallogocentric discourses. It aims to illustrate that the fictional representation of maternal neonaticide discloses exactly the pathology in the real world that devalues women and deprives them of positive social space for sublimation. It is social melancholy that constructs passive and shameful female bodies that disempower mothers. The article concludes that despite the prevalent literary discourses that assign blame to mothers, it is more constructive to look beyond the text and examine the underlying melancholy of social oppression that internalizes the sense of shame within mothers and impedes their ability to love