Search results for "Genetic algorithm"

Optimal selection of individuals for repeated covariate measurements in follow-up studies

2016

Repeated covariate measurements bring important information on the time-varying risk factors in long epidemiological follow-up studies. However, due to budget limitations, it may be possible to carry out the repeated measurements only for a subset of the cohort. We study cost-efficient alternatives for the simple random sampling in the selection of the individuals to be remeasured. The proposed selection criteria are based on forms of the D-optimality. The selection methods are compared with the simulation studies and illustrated with the data from the East–West study carried out in Finland from 1959 to 1999. The results indicate that cost savings can be achieved if the selection is focuse…

Do editors have a silver bullet? an agent-based model of peer review

2014

This paper presents an agent-based model of peer review that looks at the effect of different editorial policies of referee selection. We tested four author/referee matching scenarios as follows: random selection of referees, selection of referees with a similar status to submission authors, selection of higher-skilled and lower skilled referees. We tested these scenarios against three types of referee behaviour, i.e., fair, unreliable and strategic and measured their implications for the quality and efficiency of the process. Results show that in case of randomness of referee judgment, any editorial policy is detrimental for peer review. If referees behave strategically, certain matching p…

Do aging employees benefit from self-regulative strategies? : A follow-up study

2020

SOC-strategies (selection, optimization, and compensation) are crucial for well-being and adaptation throughout the life course. The workforce is aging rapidly, thus the age-conditional premises of SOC theory require attention. This study explored (1) whether older employees used SOC strategies more often (compared to younger employees), and (2) whether older employees benefited more from SOC strategies in relation to occupational well-being (job burnout, work engagement). The study was based on follow-up data including three occupational subsamples of different age (N = 1,020). There were no significant age-conditional differences in the take-up of SOC strategies. However, older (white-col…

Methods matter: Testing competing models for designing short-scale Big-Five assessments

2015

Abstract Many psychological instruments are psychometrically inadequate because derived person-parameters are unfounded and models will be rejected using established psychometric criteria. One strategy towards improving the psychometric properties is to shorten instruments. We present and compare the following procedures for the abbreviation of self-report assessments on the Trait Self-Description Inventory in a sample of 14,347 participants: (a) Maximizing reliability/main loadings, (b) Minimizing modification indices/cross loadings, (c) the PURIFY Algorithm in Tetrad, (d) Ant Colony Optimization, and (e) a genetic algorithm. Ant Colony Optimization was superior to all other methods in imp…

Interaction between filaggrin mutations and neonatal cat exposure in atopic dermatitis

2020

Atopic dermatitis (AD) is a prevalent inflammatory skin disease. Loss-of-function mutations in filaggrin gene (FLG) represent the strongest genetic risk factors for AD, being strongly associated with early disease onset and persistence into adulthood.1 The epidermis of individuals with mutations in FLG is fundamentally different from normal skin being characterized by increased penetration of allergens.2 Recent birth cohort studies showed a significant interaction between cat ownership at birth and mutations in FLG (R501X, 2282del4) on the development of early-onset AD.3 This finding was replicated for the 2282del4 FLG mutation in a Dutch cohort study, and extended to further associate with…

Non-chromatographic speciation

2010

We evaluate the main strategies for screening trace-element species in most types of sample to establish their strengths and weaknesses, as they offer fast, sensitive and cheaper alternatives to classical methods involving chromatography. We consider the principles of non-chromatographic speciation analysis, based on the different behaviors of chemical species before measurement by atomic and molecular spectrometry and electroanalytical methods, so as to give an update on the literature in this field of research.

Principal component analysis for the selection of variables in the application of the H-point and generalised H-point standard addition method

2000

The present paper deals with the selection of variables for the H-point and generalised H-point standard additions methods (HPSAM and GHPSAM, respectively). Both methods are applied for the resolution of spectroscopic interfered signals in the UV-vis range. The HPSAM is a suitable method for the resolution of binary and ternary mixtures when the interferent is known. The GHPSAM is applied for the resolution of samples that contain unknown interferents. In this paper, a method based on the study of a principal components analysis (PCA) for the selection of variables for the HPSAM and GHPSAM is proposed. The PCA results show the isolation of the analyte signal from the sample signal, achieved…

Comparison of selection criteria for milk yield traits of Valle del Belice dairy sheep.

2006

Abstract The objectives of this work were to investigate alternative selection criteria for milk yield traits in the Valle del Belice sheep breed, which are either corrected for lactation length or not affected by lactation length, to estimate genetic parameters for these alternative selection criteria and to compare the estimated breeding values. The genetic correlations show that corrected milk yield (CMY), maximum test-day yield (MTY) and milk yield at hundred days (MYH), are moderately or weakly correlated with lactation length (LL) ( r g  = 0.58, 0.16 and 0.39, respectively). Higher genetic correlation was found between total milk yield (TMY) and LL ( r g  = 0.73). Rank correlations be…

Identification Of P.Leu167Del Apoe Gene Mutation By Next Generation Sequencing In A Large Hypercholesterolemic Family

2019

A new approach to portfolio selection based on forecasting

2023

In this paper we analyze the portfolio selection problem from a novel perspective based on the analysis and prediction of the time series corresponding to the portfolio’s value. Namely, we define the value of a particular portfolio at the time of its acquisition. Using the time series of historical prices of the different financial assets, we calculate backward the value that said portfolio would have had in past time periods. A damped trend model is then used to analyze this time series and to predict the future values of the portfolio, providing estimates of the mean and variance for different forecasting horizons. These measures are used to formulate the portfolio selection problem, whic…