Search results for " Program"
showing 10 items of 3075 documents
Structural difficulty in grammatical evolution versus genetic programming
2013
Genetic programming (GP) has problems with structural difficulty as it is unable to search effectively for solutions requiring very full or very narrow trees. As a result of structural difficulty, GP has a bias towards narrow trees which means it searches effectively for solutions requiring narrow trees. This paper focuses on the structural difficulty of grammatical evolution (GE). In contrast to GP, GE works on variable-length binary strings and uses a grammar in Backus-Naur Form (BNF) to map linear genotypes to phenotype trees. The paper studies whether and how GE is affected by structural difficulty. For the analysis, we perform random walks through the search space and compare the struc…
On the Locality of Standard Search Operators in Grammatical Evolution
2014
Offspring should be similar to their parents and inherit their relevant properties. This general design principle of search operators in evolutionary algorithms is either known as locality or geometry of search operators, respectively. It takes a geometric perspective on search operators and suggests that the distance between an offspring and its parents should be less than or equal to the distance between both parents. This paper examines the locality of standard search operators used in grammatical evolution (GE) and genetic programming (GP) for binary tree problems. Both standard GE and GP search operators suffer from low locality since a substantial number of search steps result in an o…
Natural Language Parsing
2009
Automatic natural language processing captures a lion’s share of the attention in open information management. In one way or another, many applications have to deal with natural language input. In this chapter the authors investigate the problem of natural language parsing from the perspective of biolinguistics. They argue that the human mind succeeds in the parsing task without the help of languagespecific rules of parsing and language-specific rules of grammar. Instead, there is a universal parser incorporating a universal grammar. The main argument comes from language acquisition: Children cannot learn language specific parsing rules by rule induction due to the complexity of unconstrain…
Bicausative matrices to measure structural change: Are they a good tool?
1999
The causative-matrix method to analyze temporal change assumes that a matrix transforms one Markovian transition matrix into another by a left multiplication of the first matrix; the method is demand-driven when applied to input-output economics. An extension is presented without assuming the demand-driven or supply-driven hypothesis. Starting from two flow matrices X and Y, two diagonal matrices are searched, one premultiplying and the second postmultiplying X, to obtain a result the closer as possible to Y by least squares. The paper proves that the method is deceptive because the diagonal matrices are unidentified and the interpretation of results is unclear. Keywords : Input-Output ; Ch…
Forecast Output Coincidence and Biproportion: Two Criteria to Determine the Orientation of an Economy. Comparison for France (1980-1997)
2002
International audience; The method of forecast output coincidence used to determine if sectors are demand-sided or supply-sided in an input-output framework mixes two effects, the structural effect (choosing between demand and supply side models) and the effect of an exogenous factor (final demand or added-value). The note recalls that another method is possible, the comparison of the stability of technical and allocation coefficients, generalized by the biproportional filter: if for a sector, after biproportional filtering, column coefficients are more stable than row coefficients, then this sector is declared as not supply-sided (but one cannot decide that it is demand-sided anyway), and …
A biproportional filter to compare technical and allocation coefficient variations
1997
International audience; In input-output analysis there are two alternate possibilities between Leontief's mechanism (fixed technical coefficients) and Ghosh's mechanism (fixed allocation coefficients). Testing the long term consistency of these mechanisms entails comparing input-output matrices over time. This paper challenges the value of proportional filters (separate comparison of column and row coefficients) and introduces the biproportional filter which allows simultaneous comparison of column and rows. An application is proposed using French input-output tables for 1980 and 1993. The stability of column coefficients cannot be taken for granted and generally, for any sector, both rows …
Mathematical problem-solving in early school years with Bee-bot
2018
Los entornos relacionados con la robótica y los lenguajes visuales de programación por bloques permiten plantear tareas que pueden ser entendidas como problemas con contenido matemático aptos para edades escolares tempranas. Estos entornos permiten proponer situaciones problemáticas en edades en las que el formalismo o el escaso conocimiento matemático impide a los estudiantes abordar problemas matemáticos más complejos. En este trabajo se da cuenta de cómo el robot programable Bee-bot constituye un dispositivo privilegiado donde poder observar cómo los estudiantes toman decisiones durante el proceso de resolución. The environments related to robotics and the visual block-based programming …
3 years of liraglutide versus placebo for type 2 diabetes risk reduction and weight management in individuals with prediabetes: a randomised, double-…
2017
Background: \ud Liraglutide 3·0 mg was shown to reduce bodyweight and improve glucose metabolism after the 56-week period of this trial, one of four trials in the SCALE programme. In the 3-year assessment of the SCALE Obesity and Prediabetes trial we aimed to evaluate the proportion of individuals with prediabetes who were diagnosed with type 2 diabetes.\ud \ud Methods: \ud In this randomised, double-blind, placebo-controlled trial, adults with prediabetes and a body-mass index of at least 30 kg/m2, or at least 27 kg/m2 with comorbidities, were randomised 2:1, using a telephone or web-based system, to once-daily subcutaneous liraglutide 3·0 mg or matched placebo, as an adjunct to a reduced-…
Prevalence and impact of metabolic syndrome on hospital outcomes in acute myocardial infarction.
2005
The impact of metabolic syndrome after acute myocardial infarction (AMI) has not yet been studied. In a population-based sample of patients with AMI, we sought to determine the prevalence of metabolic syndrome in patients with AMI, its impact on hospital outcomes, and to assess the relative influence of each of the components of the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III definition of metabolic syndrome on the risk of death and heart failure.A total of 633 unselected, consecutive patients hospitalized with AMI were categorized according to the NCEP ATP III metabolic syndrome criteria (presence of/=3 of the following: hyperglycemia; triglyceride level/=…
Metabolic and cardiopulmonary effects of detraining after a structured exercise training programme in young PCOS women
2008
Summary Objective The aim of the present study was to determine if the favourable cardiopulmonary and metabolic benefits induced by exercise training (ET) programme are maintained after its cessation. Patients Thirty-two young overweight polycystic ovary syndrome (PCOS) women matched for age and body mass index (BMI) with other 32 PCOS patients was enrolled. The first group [PCOS-T (trained)] underwent 24-week ET programme, whereas the second [PCOS-DT (detrained)] underwent 12-week ET programme followed by 12-week detraining period. Methods At baseline, after 12- and 24-week follow-up, all PCOS women were studied for their hormonal (ovarian and adrenal androgens), metabolic (glucose and …