Direct formulation to Cholesky decomposition of a general nonsingular correlation matrix

We present two novel, explicit representations of Cholesky factor of a nonsingular correlation matrix. The first representation uses semi-partial correlation coefficients as its entries. The second, uses an equivalent form of the square roots of the differences between two ratios of successive determinants. Each of the two new forms enjoys parsimony of notations and offers a simpler alternative to both spherical factorization and the multiplicative partial correlation Cholesky matrix (Cooke et al 2011). Two relevant applications are offered for each form: a simple $t$-test for assessing the independence of a single variable in a multivariate normal structure, and a straightforward algorithm for generating random positive-definite correlation matrix. The second representation is also extended to any nonsingular hermitian matrix.Comment: Accepted to Statistics and Probability Letters, March 201

Identification of tau leptons at the DZero experiment

The article describes the identification of hadronically decaying tau leptons in ppbar collisions at 1.96 TeV collected by the DZero detector at the Fermilab Tevatron. After a brief description of the motivations and the challenges of considering tau leptons in high energy hadronic collisions, details of the tau reconstruction and identification will be discussed. The challenges associated for tau energy measurements in an hadronic environment will be presented including approaches to deal with such measurements

Wastewater treatment and reuse: an institutional analysis for Hyderabad, India

River basinsWater pollutionSewageEffluentsPollution controlLegislationWaste managementWater qualityGuidelinesWastewater irrigationHealth hazardsRiceGrassesInstitutional reformCase studies

Assessing the outcomes of IWMI’s research and interventions on irrigation management transfer

Irrigation management / Participatory management / Privatization / Water users associations / Farmers associations / Gender

Livelihoods and gender roles in drip-irrigation technology: A case of Nepal

Gender / Drip irrigation / Technology / Rural women / Empowerment / Vegetables / Family income / Households / Villages / Farmers / Economic aspects

Locating the poor: Spatially disaggregated poverty maps for Sri Lanka

Poverty / Mapping

Assessing the student: the PechaKucha approach

With creativity and innovation as dominant buzzwords in higher education, employing PechaKucha to assess students is worth exploring

“Being black”: what is it cool for?

Dr Poonam Madar lectures in Sociology and Criminology, based in London. Her research interests include race, gender, and popular culture. She blogs at: www.poonammadar.blogspot.com and she tweets as @PoonamMadar To find out more, visit Poonam’s Facebook page at: www.facebook.com/PoonamMadar Not so long ago I began temping in an office in Central London. In the first few days, one staff member (a black man) welcomed me and we exchanged ‘hellos’. But when I asked his name, his eyes signalled to the further part of the room where the senior managers were sitting and he laughingly, but sarcastically replied, ‘They call me equal opportunities.’ Before I could react or even have the chance to catch his ‘real’ name he was already out the door