Building an OSS Quality Estimation Model with CATREG

Open Source Software (OSS) has been a popular form in software development. In this paper, we use statistical approaches to deriveOSSquality estimation models. Our objective is to build estimation models for the number of defects with metrics at project levels. First CATREG (Categorical regression with optimal scaling) is used to obtain quantifications of the qualitative variables. Then the independent variables are validated using the stepwise linear regression. The process is repeated to acquire optimal quantifications and final regression formula. This modeling process is performed based on data from theOSScommunities and is proved to be practically valuable

Legal origin, colonial origin and deforestation

This paper investigates whether inherited legacies such as legal origin allow of explaining deforestation in 110 developed and developing countries. The hypothesis is that differences in deforestation between countries can be attributed to their legal systems. Also, since nearly all common law countries are former English colonies, and nearly all civil law countries were colonized by France, Spain or Portugal, legal origin and colonial history are strongly correlated, so that one can not attribute all the variance to the effect of the legal system. What is found overall is that (i) French civil law countries deforest less than English common law ones within the total sample, within the sample of colonized countries, and within the sample of tropical developing countries; (ii) Former French colonies deforest less than former English colonies. These results hold when geography features are controlled for since the process of colonization was not random and depended on initial geographic and climatic conditions.Deforestation; Colonial legacies; Legal origin

Legal origin, colonial origin and deforestation

This paper investigates whether inherited legacies such as legal origin allow of explaining deforestation in 110 developed and developing countries. The hypothesis is that differences in deforestation between countries can be attributed to their legal systems. Also, since nearly all common law countries are former English colonies, and nearly all civil law countries were colonized by France, Spain or Portugal, legal origin and colonial history are strongly correlated, so that one can not attribute all the variance to the effect of the legal system. What is found overall is that (i) French civil law countries deforest less than English common law ones within the total sample, within the sample of colonized countries, and within the sample of tropical developing countries; (ii) Former French colonies deforest less than former English colonies. These results hold when geography features are controlled for since the process of colonization was not random and depended on initial geographic and climatic conditions.Deforestation; Colonial legacies; Legal origin

Origin of Life

The evolution of life has been a big enigma despite rapid advancements in the fields of biochemistry, astrobiology, and astrophysics in recent years. The answer to this puzzle has been as mind-boggling as the riddle relating to evolution of Universe itself. Despite the fact that panspermia has gained considerable support as a viable explanation for origin of life on the Earth and elsewhere in the Universe, the issue remains far from a tangible solution. This paper examines the various prevailing hypotheses regarding origin of life like abiogenesis, RNA World, Iron-sulphur World, and panspermia; and concludes that delivery of life-bearing organic molecules by the comets in the early epoch of the Earth alone possibly was not responsible for kick-starting the process of evolution of life on our planet.Comment: 32 pages, 8 figures,invited review article, minor additio

The Origin of Mass

The quark-lepton mass problem and the ideas of mass protection are reviewed. The hierarchy problem and suggestions for its resolution, including Little Higgs models, are discussed. The Multiple Point Principle is introduced and used within the Standard Model to predict the top quark and Higgs particle masses. Mass matrix ans\"{a}tze are considered; in particular we discuss the lightest family mass generation model, in which all the quark mixing angles are successfully expressed in terms of simple expressions involving quark mass ratios. It is argued that an underlying chiral flavour symmetry is responsible for the hierarchical texture of the fermion mass matrices. The phenomenology of neutrino mass matrices is briefly discussed.Comment: 33 pages, 7 figures, to be published in the Proceedings of the XXXI ITEP Winter School, Moscow, Russia, 18 - 26 February 200

COSMOLOGICAL ORIGIN OF QUASARS

Quasars are the earliest objects known to exist. We examine their origin in the context of popular models for structure formation in the universe. We show that seeds for quasar black holes could have originated from the initial cosmological collapse of overdense regions with unusually small rotation. Most of these seeds have a mass of order 10^6 solar masses, just above the cosmological Jeans mass. For Cold Dark Matter cosmologies, we find of order one seed black hole per bright galaxy. After the galaxy forms, the seeds inside its bulge sink to the center by dynamical friction. We also describe a few empirical methods to study the properties of quasars and their environments. These include: probing quasar hosts through [C II] emission, finding quasar lifetimes from the ``proximity effect'' along two lines of sight, and measuring the amplitude of clustering at high redshifts through the detection of Lyman-alpha clouds beyond the quasar redshift.Comment: 5 pages, Standard Tex, contribution to the Texas symposium in Munich, Dec. 1994

Statistical Origin of Gravity

Starting from the definition of entropy used in statistical mechanics we show that it is proportional to the gravity action. For a stationary black hole this entropy is expressed as $S = E/ 2T$, where $T$ is the Hawking temperature and $E$ is shown to be the Komar energy. This relation is also compatible with the generalised Smarr formula for mass.Comment: LaTex, 7 pages, no figure, minor clarifications, references added, to appear in Phys. Rev.