tolerance: An R Package for Estimating Tolerance Intervals

The tolerance package for R provides a set of functions for estimating and plotting tolerance limits. This package provides a wide-range of functions for estimating discrete and continuous tolerance intervals as well as for estimating regression tolerance intervals. An additional tool of the tolerance package is the plotting capability for the univariate and regression settings as well as for the multivariate normal setting. The tolerance package's capabilities are illustrated using simulated data sets. Formulas used for the estimation procedures are also presented.

Spiders (Arachnida: Araneae) of Saba Island, Lesser Antilles: Unusually high species richness indicates the Caribbean Biodiversity Hotspot is woefully undersampled

Saba Island (Caribbean Netherlands) is one of the northernmost islands of the Lesser Antilles. It is only 13 square kilometers but contains a wide variety of potential spider habitats including dry, moist, and elfin forests. As part of a collaborative effort between Conservation International and Saba Conservation Foundation, during a several week period in March and May 2008 we briefly surveyed the island for spiders and other arthropods. This survey, the first for spiders of Saba, resulted in the identification of 18 families and 76 spider species, including six new species that will be described elsewhere and may be endemic to Saba. The species richness of Saba’s spider fauna is considerably higher than that reported from other small Caribbean islands. We conclude this is probably a combined result of undersampling and lower habitat diversity on these other islands

Evidence of a glass transition in a 10-state non-mean-field Potts glass

Potts glasses are prototype models that have been used to understand the structural glass transition. However, in finite space dimensions a glass transition remains to be detected in the 10-state Potts glass. Using a one-dimensional model with long-range power-law interactions we present evidence that a glass transition below the upper critical dimension can exist for short-range systems at low enough temperatures. Gaining insights into the structural glass transition for short-range systems using spin models is thus potentially possible, yet difficult.Comment: 4 pages, 1 table, 2 figure

Exploring the Roper wave function in Lattice QCD

Using a correlation matrix analysis consisting of a variety of smearings, the CSSM Lattice collaboration has successfully isolated states associated with the Roper resonance and other "exotic" excited states such as the $\Lambda(1405)$ on the lattice at near-physical pion masses. We explore the nature of the Roper by examining the eigenvectors that arise from the variational analysis, demonstrating that the Roper state is dominated by the $\chi_1$ nucleon interpolator and only poorly couples to $\chi_2.$ By examining the probability distribution of the Roper on the lattice, we find a structure consistent with a constituent quark model. In particular, the Roper $d$-quark wave function contains a single node consistent with a $2S$ state. A detailed comparison with constituent quark model wave functions is carried out, validating the approach of accessing these states by constructing a variational basis composed of different levels of fermion source and sink smearing.Comment: 7 pages, 5 figures; presented at the 31st International Symposium on Lattice Field Theory (Lattice 2013), 29 July - 3 August 2013, Mainz, German

Exotic Statistics for Strings in 4d BF Theory

After a review of exotic statistics for point particles in 3d BF theory, and especially 3d quantum gravity, we show that string-like defects in 4d BF theory obey exotic statistics governed by the 'loop braid group'. This group has a set of generators that switch two strings just as one would normally switch point particles, but also a set of generators that switch two strings by passing one through the other. The first set generates a copy of the symmetric group, while the second generates a copy of the braid group. Thanks to recent work of Xiao-Song Lin, we can give a presentation of the whole loop braid group, which turns out to be isomorphic to the 'braid permutation group' of Fenn, Rimanyi and Rourke. In the context 4d BF theory this group naturally acts on the moduli space of flat G-bundles on the complement of a collection of unlinked unknotted circles in R^3. When G is unimodular, this gives a unitary representation of the loop braid group. We also discuss 'quandle field theory', in which the gauge group G is replaced by a quandle.Comment: 41 pages, many figures. New version has minor corrections and clarifications, and some added reference

The Use of Brands in Food Marketing - Results from a Survey of Danish Food Industry Firms

The paper tests a number of hypotheses concerning branding behaviour of the food industry found in the literature. Based on a survey of 109 Danish food industry firms conducted in 2004, three aspects of branding strategies are analysed, i) the number of brands owned by the firm, ii) the number of brands introduced by the firm during the past year and iii) the percentage of sales obtained from production under private labels. Firms' branding behaviour is related to structural variables including firm size, degree of vertical integration, value added as well as firms' views on food chain organisation and competitiveness.Brands, Private labels, Food industry, Survey, Marketing, Q13,

Password Cracking and Countermeasures in Computer Security: A Survey

With the rapid development of internet technologies, social networks, and other related areas, user authentication becomes more and more important to protect the data of the users. Password authentication is one of the widely used methods to achieve authentication for legal users and defense against intruders. There have been many password cracking methods developed during the past years, and people have been designing the countermeasures against password cracking all the time. However, we find that the survey work on the password cracking research has not been done very much. This paper is mainly to give a brief review of the password cracking methods, import technologies of password cracking, and the countermeasures against password cracking that are usually designed at two stages including the password design stage (e.g. user education, dynamic password, use of tokens, computer generations) and after the design (e.g. reactive password checking, proactive password checking, password encryption, access control). The main objective of this work is offering the abecedarian IT security professionals and the common audiences with some knowledge about the computer security and password cracking, and promoting the development of this area.Comment: add copyright to the tables to the original authors, add acknowledgement to helpe

Maize Revolutions in Sub-Saharan Africa

There have been numerous episodes of widespread adoption of improved seed and long-term achievements in the development of the maize seed industry in Sub-Saharan Africa. This summary takes a circumspect view of technical change in maize production. Adoption of improved seed has continued to rise gradually, now representing an estimated 44 percent of maize area in Eastern and Southern Africa (outside South Africa), and 60 percent of maize area in West and Central Africa. Use of fertilizer and restorative crop management practices remains relatively low and inefficient. An array of extension models has been tested and a combination of approaches will be needed to reach maize producers in heterogeneous agricultural environments. Yield growth overall has been 1 percent over the past half-century, although this figure masks the high variability in maize yields, as well as improvements in resistance to disease and abiotic pressures that would have caused yield decline in the absence of maize breeding progress. The authors argue that conducive policies are equally, if not more, important for maize productivity in the region than the development of new technology and techniques. Currently popular, voucher-based subsidies can “crowd out” the private sector and could be fiscally unsustainable.Sub-Saharan Africa, maize, seed, Agricultural and Food Policy, Production Economics,

Extracting Low-Lying Lambda Resonances Using Correlation Matrix Techniques

The lowest-lying negative-parity state of the Lambda is investigated in (2+1)-flavour full-QCD on the PACS-CS configurations made available through the ILDG. We show that a variational analysis using multiple source and sink smearings can extract a state lying lower than that obtained by using a standard fixed smeared source and sink operator alone.Comment: 3 pages, 1 figure, submitted to the proceedings of T(R)OPICAL QCD II, Cairns, Australia, 201