Computing the Kolmogorov-Smirnov Distribution when the Underlying cdf is Purely Discrete, Mixed or Continuous

The distribution of the Kolmogorov-Smirnov (K-S) test statistic has been widely studied under the assumption that the underlying theoretical cdf, F(x), is continuous. However, there are many real-life applications in which fitting discrete or mixed distributions is required. Nevertheless, due to inherent difficulties, the distribution of the K-S statistic when F(x) has jump discontinuities has been studied to a much lesser extent and no exact and efficient computational methods have been proposed in the literature. In this paper, we provide a fast and accurate method to compute the (complementary) cdf of the K-S statistic when F(x) is discontinuous, and thus obtain exact p values of the K-S test. Our approach is to express the complementary cdf through the rectangle probability for uniform order statistics, and to compute it using Fast Fourier Transform(FFT). Secondly, we provide a C++ and an R implementation of the proposed method, which fills in the existing gap in statistical software. We give also a useful extension of the Schmid’s asymptotic formula for the distribution of the K-S statistic, relaxing his requirement for F(x) to be increasing between jumps and thus allowing for any general mixed or purely discrete F(x). The numerical performance of the proposed FFT-based method, implemented both in C++ and in the R package KSgeneral, is illustrated when F(x) is mixed, purely discrete, and continuous. The performance of the general asymptotic formula is also studied

Effects of Cigarette Butts Extract on the Mortality of Mosquito Wrigglers

The study aimed to determine the effects of cigarette butt extract on the mortality of mosquito wrigglers. It is an experimental research using true experimental design. Mosquito wrigglers collected were randomly selected with 10 wrigglers each treatment. The containers used for the treatment were randomly arrangedfollowing the complete randomized block design with 3 replicates each treatment. Five treatments were tested: T1 Control1 (Water); T2 Control2 (Extract from new filter);T31 used cig-butt/li sdw/period of exposure (pE) until death of wrigglers; T4 2 used cig-butt/li sdw/pE; T5 3 used cig-butt/li sdw/pE where 24 hours was the period offilter/cig-butt extraction or simple water soaking of cig-butt, and new filter for control. Mosquito wrigglers were collected using an empty aquarium. These treatments were unsuccessful. Modifications were made on the number of cig-butts, quantity of water, period of soaking/extraction of cig-butts and the period of exposure. When the cig-butts were soaked for 48 hours, mosquito wrigglers all died in T4 and T5 after 15 hours period of exposure. No wriggler died in T3 . Result of the experiment for the 4 trials revealed that the more cigarette butts extracted for a given quantity of water will kill mosquito wrigglers when exposed longer to the treatment. Keywords: cigarette butt, extract, mortality, wriggler

A heterotic sigma model with novel target geometry

We construct a (1,2) heterotic sigma model whose target space geometry consists of a transitive Lie algebroid with complex structure on a Kaehler manifold. We show that, under certain geometrical and topological conditions, there are two distinguished topological half--twists of the heterotic sigma model leading to A and B type half--topological models. Each of these models is characterized by the usual topological BRST operator, stemming from the heterotic (0,2) supersymmetry, and a second BRST operator anticommuting with the former, originating from the (1,0) supersymmetry. These BRST operators combined in a certain way provide each half--topological model with two inequivalent BRST structures and, correspondingly, two distinct perturbative chiral algebras and chiral rings. The latter are studied in detail and characterized geometrically in terms of Lie algebroid cohomology in the quasiclassical limit.Comment: 83 pages, no figures, 2 references adde

Aharonov-Bohm oscillations of a tunable quantum ring

With an atomic force microscope a ring geometry with self-aligned in-plane gates was directly written into a GaAs/AlGaAs-heterostructure. Transport measurements in the open regime show only one transmitting mode and Aharonov-Bohm oscillations with more than 50% modulation are observed in the conductance. The tuning via in-plane gates allows to study the Aharonov-Bohm effect in the whole range from the open ring to the Coulomb-blockade regime.Comment: 3 pages, 3 figure

Exciton energy transfer in nanotube bundles

Photoluminescence is commonly used to identify the electronic structure of individual nanotubes. But, nanotubes naturally occur in bundles. Thus, we investigate photoluminescence of nanotube bundles. We show that their complex spectra are simply explained by exciton energy transfer between adjacent tubes, whereby excitation of large gap tubes induces emission from smaller gap ones via Forster interaction between excitons. The consequent relaxation rate is faster than non-radiative recombination, leading to enhanced photoluminescence of acceptor tubes. This fingerprints bundles with different compositions and opens opportunities to optimize them for opto-electronics.Comment: 5 pages, 5 figure

Advances in the LED Materials and Architectures fro Energy-Saving Solid State Lighting towards Lighting Revolution

Cataloged from PDF version of article.In this paper, we review the recent developments (in years 2010–2011) of energysaving solid-state lighting. The industry of white light-emitting diodes (LEDs) has made significant progress, and today, white LED market is increasing (mostly with increasing LED screen and LED TV sales). The so-called Blighting revolution[ has not yet really happened on a wide scale because of the lighting efficiency at a given ownership cost. Nevertheless, the rapid development of the white LEDs is expected to soon trigger and expand the revolution

A Remark on the Renormalization Group Equation for the Penner Model

It is possible to extract values for critical couplings and gamma_string in matrix models by deriving a renormalization group equation for the variation of the of the free energy as the size N of the matrices in the theory is varied. In this paper we derive a ``renormalization group equation'' for the Penner model by direct differentiation of the partition function and show that it reproduces the correct values of the critical coupling and gamma_string and is consistent with the logarithmic corrections present for g=0,1.Comment: LaTeX, 5 pages, LPTHE-Orsay-94-5

Variation of cultivated mungbean and wild vigna as revealed by random amplified polymorphic DNA markers

The genetic variation of nine varieties of cultivated mungbean (Vigna radiata) and three local populations of wild Vigna (V. trinervia) were evaluated in this study using RAPD markers. A total of 65 scorable DNA fragments ranging in size from 173-1,500 bp were obtained from the PCR amplification usingfive RAPD primers of which 95.38% were polymorphic. Cluster analysis revealed two major groups in which the first group consists of the nine varieties ofV. radiata, while the second group includes the three populations ofV. trinervia. This information is useful for plant breeders to make informed decisions in an effort to devise breeding or crossbreeding programmes for the development of the crop

Three fermions in a box at the unitary limit: universality in a lattice model

We consider three fermions with two spin components interacting on a lattice model with an infinite scattering length. Low lying eigenenergies in a cubic box with periodic boundary conditions, and for a zero total momentum, are calculated numerically for decreasing values of the lattice period. The results are compared to the predictions of the zero range Bethe-Peierls model in continuous space, where the interaction is replaced by contact conditions. The numerical computation, combined with analytical arguments, shows the absence of negative energy solution, and a rapid convergence of the lattice model towards the Bethe-Peierls model for a vanishing lattice period. This establishes for this system the universality of the zero interaction range limit.Comment: 6 page