The Hunting of the Bump: On Maximizing Statistical Discrepancy

Anomaly detection has important applications in biosurveilance and environmental monitoring. When comparing measured data to data drawn from a baseline distribution, merely, finding clusters in the measured data may not actually represent true anomalies. These clusters may likely be the clusters of the baseline distribution. Hence, a discrepancy function is often used to examine how different measured data is to baseline data within a region. An anomalous region is thus defined to be one with high discrepancy. In this paper, we present algorithms for maximizing statistical discrepancy functions over the space of axis-parallel rectangles. We give provable approximation guarantees, both additive and relative, and our methods apply to any convex discrepancy function. Our algorithms work by connecting statistical discrepancy to combinatorial discrepancy; roughly speaking, we show that in order to maximize a convex discrepancy function over a class of shapes, one needs only maximize a linear discrepancy function over the same set of shapes. We derive general discrepancy functions for data generated from a one- parameter exponential family. This generalizes the widely-used Kulldorff scan statistic for data from a Poisson distribution. We present an algorithm running in $O(\smash[tb]{\frac{1}{\epsilon} n^2 \log^2 n})$ that computes the maximum discrepancy rectangle to within additive error $\epsilon$, for the Kulldorff scan statistic. Similar results hold for relative error and for discrepancy functions for data coming from Gaussian, Bernoulli, and gamma distributions. Prior to our work, the best known algorithms were exact and ran in time $\smash[t]{O(n^4)}$.Comment: 11 pages. A short version of this paper will appear in SODA06. This full version contains an additional short appendi

GRA Coupled with Fuzzy Linguistic Reasoning for Quality Productivity Improvement in Electrical Discharge Machining (EDM)

In the present work, the use of the grey relational analysis and fuzzy logic combined with Taguchi method has been proposed for optimizing Electrical Discharge Machining (EDM) process with multiple responses involved. The study aims at simultaneous optimization of quality and productivity. Quality and productivity are correlated inversely. If product quality is intended to be increased then extent of productivity is to be compromised and vice versa. Therefore, a compatible balance is necessary between productivity and product quality. The study addresses a case study related to EDM in which material removal rate (MRR) and surface roughness (Ra value) of the machined work surface have been optimized

Synthesis, Biological, Spectral, and Thermal Investigations of Cobalt(II) and Nickel(II) Complexes of N-Isonicotinamido -2′,4′-Dichlorobenzalaldimine

A new series of 12 complexes of cobalt(II) and nickel(II) with N-isonicotinamido-2′,4′-dichlorobenzalaldimine (INH-DCB) with the general composition MX(2) · n(INH-DCB) [M = Co(II) or Ni(II), X = Cl(−) ,Br(−), NO(3)(−), NCS(−), or CH(3)COO(−), n = 2; X = ClO(4) (−), n = 3] have been synthesized. The nature of bonding and the stereochemistry of the complexes have been deduced from elemental analyses, infrared, electronic spectra, magnetic susceptibility, and conductivity measurements. An octahedral geometry has been suggested for all the complexes. The metal complexes were screened for their antifungal and antibacterial activities on different species of pathogenic fungi and bacteria and their biopotency has been discussed

Modeling item--item similarities for personalized recommendations on Yahoo! front page

We consider the problem of algorithmically recommending items to users on a Yahoo! front page module. Our approach is based on a novel multilevel hierarchical model that we refer to as a User Profile Model with Graphical Lasso (UPG). The UPG provides a personalized recommendation to users by simultaneously incorporating both user covariates and historical user interactions with items in a model based way. In fact, we build a per-item regression model based on a rich set of user covariates and estimate individual user affinity to items by introducing a latent random vector for each user. The vector random effects are assumed to be drawn from a prior with a precision matrix that measures residual partial associations among items. To ensure better estimates of a precision matrix in high-dimensions, the matrix elements are constrained through a Lasso penalty. Our model is fitted through a penalized-quasi likelihood procedure coupled with a scalable EM algorithm. We employ several computational strategies like multi-threading, conjugate gradients and heavily exploit problem structure to scale our computations in the E-step. For the M-step we take recourse to a scalable variant of the Graphical Lasso algorithm for covariance selection. Through extensive experiments on a new data set obtained from Yahoo! front page and a benchmark data set from a movie recommender application, we show that our UPG model significantly improves performance compared to several state-of-the-art methods in the literature, especially those based on a bilinear random effects model (BIRE). In particular, we show that the gains of UPG are significant compared to BIRE when the number of users is large and the number of items to select from is small. For large item sets and relatively small user sets the results of UPG and BIRE are comparable. The UPG leads to faster model building and produces outputs which are interpretable.Comment: Published in at http://dx.doi.org/10.1214/11-AOAS475 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Utility of Papanicolaou test in diagnosis of cervical lesions: a study in a tertiary care centre of western Uttar Pradesh

Background: Cervical cancer is the most common cancer among females in India. It is also one of the major causes of deaths among them. Papanicolaou (Pap) cytological test helps in detecting the early epithelial abnormalities in cervical cells. The morbidity and mortality due to cervical cancer has come down in countries with well-established screening programmes at national level. This study was conducted to emphasize the value of cervical screening as a tool for early detection of non-neoplastic and neoplastic lesions of cervix. Slide positivity rate was computed and clinico-pathological correlation was done.Methods: This cross-sectional study was conducted from January 2012 to December 2014 (3 years), on 2202 women aged between 20-70 years coming for a Pap smear examination in a tertiary care hospital in Bareilly, India. After staining with conventional Papanicolaou technique, all cases were classified as per Bethesda nomenclature (2001).Results: Out of 2202 cases, 85.16% slides were found to be negative for intraepithelial abnormalities and 14.84% slides were labelled as positive for epithelial lesions. 97.67% of high grade lesions were found in women more than 40 years. Smears with epithelial cell abnormality were found more common in older age groups whereas smears negative for epithelial cell abnormality were found more common in young age groups.Conclusion: Pap test is a cost effective cancer screening and is a simple method to detect various lesions of cervix, non-neoplastic as well as neoplastic. High risk screening programmes should be directed to all women >40 years. Pap test is especially useful to diagnose precancerous lesions of cervix, thereby early detection of these lesions & subsequent proper treatment can be helpful in prevention of cervical cancer.

Uma Abordagem de Comunicação para o Desenvolvimento na Erradicação da Poliomielite: a Índia como um caso de sucesso: divulgação, extensão e estratégia interpessoal

A comunicação para o desenvolvimento (C4D) foi identificada como um fator importante na erradicação da poliomielite na Índia. A Índia foi aclamada como um caso de sucesso, pois conheceu a utilização inovadora de dados epidemiológicos e a aplicação de múltiplos canais de comunicação, especialmente para o programa de erradicação da poliomielite. Também se percebeu que a comunicação para a erradicação da poliomielite promoveu principalmente a queda da vacina contra a poliomielite, enquanto os principais fatores causais, como baixas taxas de imunização de rotina, falta de saneamento básico, falta de água potável e nutrição inadequada, responsáveis ​​pela disseminação do vírus da poliomielite, não têm sido promovidos, enquanto conteúdo da mudança de comportamento. A pesquisa foi realizada em aglomerados suburbanos em torno da capital Delhi, habitada por migrantes de dois estados indianos. A pesquisa documentou que o conhecimento e as perceções de um grande número de comunidades são muito baixos, em relação à recuperação de quaisquer fatores causais que levam à transmissão da poliomielite. A investigação concluiu que, para que os comportamentos mudem, é necessário ter em conta tabus culturais, normas sociais e desigualdades estruturais, incluindo uma ênfase especial nos colonos migrantes. As estratégias de comunicação devem estar cientes e sintonizadas com o ambiente político e legislativo e também vinculadas aos aspetos de prestação de serviços para os mais vulneráveis ​​e excluídos socialmente

RECENT ADVANCEMENT, TECHNOLOGY & APPLICATIONS OF MULTIPLE EMULSIONS

Multiple emulsions are complex polydispersed systems where both oil in water and water in oil emulsion exists simultaneously which are stabilized by lipophilic and hydrophilic surfactants respectively. The ratio of these surfactants is important in achieving stable multiple emulsions. Among water-in-oil-in-water (w/o/w) and oil-in-water-in-oil (o/w/o) type multiple emulsions, the former has wider areas of application and hence are studied in great detail. Formulation, preparation techniques and in vitro characterization methods for multiple emulsions are reviewed. Various factors affecting the stability of multiple emulsions and the stabilization approaches with specific reference to w/o/w type multiple emulsions are discussed in detail. Favorable drug release mechanisms and/or rate along with in vivo fate of multiple emulsions make them a versatile carrier. It finds wide range of applications in controlled or sustained drug delivery, targeted delivery, taste masking, bioavailability enhancement, enzyme immobilization, etc. Multiple emulsions have also been employed as intermediate step in the microencapsulation process and are the systems of increasing interest for the oral delivery of hydrophilic drugs, which are unstable in gastrointestinal tract like proteins and peptides. With the advancement in techniques for preparation, stabilization and rheological characterization of multiple emulsions, it will be able to provide a novel carrier system for drugs, cosmetics and pharmaceutical agents. In this review, emphasis is laid down on formulation, stabilization techniques and potential applications of multiple emulsion system