A Standardized Treatment of Binary Similarity Measures with an Introduction to k-Vector Percentage Normalized Similarity

This paper attempts to codify a standard nomenclature for similarity measures based on recent literature and to advance the field of similarity measures through the introduction of non-binary similarity between more than two attribute vectors

Airline Price Discrimination

Price discrimination enjoys a long history in the airline industry. Borenstein (1989) discusses price discrimination through frequent flyer programs from 1985 as related to the Piedmont-US Air merger, price discrimination strategies have grown in size and scope since then. From Saturday stay over requirements to varying costs based on time of purchase, the airline industry is uniquely situated to enjoy the fruits of price discrimination

Fukushima: The Failure of Predictive Models

Linear regression is an attempt to build a model from existing data. It uses the existing data to fit a linear equation that exhibits the least error from the actual points. Even within the existing data, a regression equation has limited ability to predict actual dependent variable values. Linear regression is limited in several ways; it assumes only linear relationships between variables, it is very sensitive to outliers, and data points must be independent. If any of these assumptions are not met the models get less accurate. Often random error (residuals) are enough to reduce the quality of fit of the equation to where it is unable to predict any values within the range of the original data except (x ̅,y ̅). Even with the best coefficient of determination (R2=1), data within the sample set may not be indicative of the condition outside the sample set

The Effects of Non-Existent Property Ownership Rights Within the Electricity Production Sector on Labor Force Participation in the Dominican Republic

The labor market in the Dominican Republic is in disarray. There has been a high rate of unemployment and a very high rate of non-participation within the labor force for years. Output growth has been steady in manufacturing, telecommunication, and financial services, and new jobs have been added in the service sector consistently, however these gains have led to no real increase in available quality jobs and wage stagnation (Williams & Adedeji, 2004). Abdullaev and Marcello (2013) describe a dichotomous approach to solving the problem; through targeted education for the long term and through product market reforms in the near term. The energy sector in the Dominican Republic is a prime example of an area where reforms are needed to improve the operating environment to spur and sustain growth. At present the losses in transmission and distribution are significantly higher than in most places as a result of fraud (Smith 2004). Until recently it has not been against the law to steal electricity (Enerdata 2011). The rationale being that if electricity is a basic human right we cannot punish those who attempt to gain it. This lack of property law within the context of electricity underpins a significant failure by the government when viewed from the point of the electricity producers. Property ownership is a fundamental concept of free markets. Without ownership rights there is no (or limited) ability to charge for goods produced with that property. Electricity is a commodity property and without the ability to effectively charge for its consumption the producers have struggled

Characterising Ultrafine Particles at Heathrow Airport

Exposure to ultrafine particles (UFP) is increasingly associated with adverse health outcomes. However, measurement of UFP in the ambient environment is generally not widespread, which limits both understanding and data for detailed assessment of the health impact. Of particular interest is the impact of airport and aircraft activities on UFP concentrations, as there are no abatement strategies for emissions from aircraft engines and jet fuel typically has a relatively high sulphur content, which can contribute to UFP formation during combustion. Three UFP measurement studies were undertaken between 2016 and 2019 to progressively understand the environment around Heathrow Airport: • The study in 2016 was carefully arranged to put airport measurements into context with representative traffic, residential and rural measurements in the south of England. As far as possible, the analysers, configurations and QA/QC used at the airport was the same as the analysers used in the UK regulatory monitoring network. The results clearly show that local airport activity has a very significant effect on local concentrations. The size distribution of airport-related UFP was seen to be different to other locations; particles smaller than 30 nm were observed in far higher numbers at the airport. Departing aircraft were associated with higher UFP concentrations than arriving aircraft. • The 2017 study was designed to just investigate particles smaller than 100 nm, at a faster time resolution than conventional analyser configurations. This study confirmed UFP measurements were greater in number concentration from departing aircraft and also from larger aircraft within that subset. • The 2019 study made use of a very fast UFP analyser, accurate aircraft location data and meteorology to uniquely associate UFP measurements with individual aircraft. The data were used to calculate emission rates for each aircraft type, which were found to be much higher than stated literature values. This is almost certainly due to measurement of condensable particles not accounted for in the published literature data. Larger and older aircraft were associated with higher measurements and emission rates, not necessarily mitigated by carrying more passengers. In 2021, the World Health Organization published guidance for recommended maximum hourly and daily exposure to UFP. The recorded measurements from all three studies exceeded these guide values; UFP exposure at large airports will be a key area of interest for future research and health assessments

Airline Price Discrimination

Price discrimination enjoys a long history in the airline industry. Borenstein (1989) discusses price discrimination through frequent flyer programs from 1985 as related to the Piedmont-US Air merger, price discrimination strategies have grown in size and scope since then. From Saturday stay over requirements to varying costs based on time of purchase, the airline industry is uniquely situated to enjoy the fruits of price discrimination

Fukushima: The Failure of Predictive Models

Linear regression is an attempt to build a model from existing data. It uses the existing data to fit a linear equation that exhibits the least error from the actual points. Even within the existing data, a regression equation has limited ability to predict actual dependent variable values. Linear regression is limited in several ways; it assumes only linear relationships between variables, it is very sensitive to outliers, and data points must be independent. If any of these assumptions are not met the models get less accurate. Often random error (residuals) are enough to reduce the quality of fit of the equation to where it is unable to predict any values within the range of the original data except (x ̅,y ̅). Even with the best coefficient of determination (R2=1), data within the sample set may not be indicative of the condition outside the sample set

Sampling for Variance in a Population

Determining confidence intervals for a population µ estimate from a sample ¯x with a either a known or an unknown population σ use similar methods. The more data one has to begin with the better will be the estimate, so knowing the standard deviation of the population will provide a better estimate of the mean. In our case we have no data to begin with so must collect the data to build our estimates. This eliminates the possibility of estimating the confidence interval of µ with a known σ, which is the better of the estimates, and has a narrower range. The data collection and calculation of s and ¯x will be necessary in our case. Once those two estimators are calculated, finding the confidence interval is an easy task

Mutation of Arabidopsis SPLICEOSOMAL TIMEKEEPER LOCUS1 Causes Circadian Clock Defects

The circadian clock plays a crucial role in coordinating plant metabolic and physiological functions with predictable environmental variables, such as dusk and dawn, while also modulating responses to biotic and abiotic challenges. Much of the initial characterization of the circadian system has focused on transcriptional initiation, but it is now apparent that considerable regulation is exerted after this key regulatory step. Transcript processing, protein stability, and cofactor availability have all been reported to influence circadian rhythms in a variety of species. We used a genetic screen to identify a mutation within a putative RNA binding protein (SPLICEOSOMAL TIMEKEEPER LOCUS1 [STIPL1]) that induces a long circadian period phenotype under constant conditions. STIPL1 is a homolog of the spliceosomal proteins TFP11 (Homo sapiens) and Ntr1p (Saccharomyces cerevisiae) involved in spliceosome disassembly. Analysis of general and alternative splicing using a high-resolution RT-PCR system revealed that mutation of this protein causes less efficient splicing of most but not all of the introns analyzed. In particular, the altered accumulation of circadian-associated transcripts may contribute to the observed mutant phenotype. Interestingly, mutation of a close homolog of STIPL1, STIP-LIKE2, does not cause a circadian phenotype, which suggests divergence in function between these family members. Our work highlights the importance of posttranscriptional control within the clock mechanism. © 2012 American Society of Plant Biologists. All rights reserved