As was shown recently, the measurement errors in regressors affect only the power of the rank test, but not its critical region. Noting that, we study the effect of measurement errors on R-estimators in linearmodel. ...
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As was shown recently, the measurement errors in regressors affect only the power of the rank test, but not its critical region. Noting that, we study the effect of measurement errors on R-estimators in linearmodel. It is demonstrated that while an R-estimator admits a local asymptotic bias, its bias surprisingly depends only on the precision of measurements and does neither depend on the chosen rank test score-generating function nor on the regressionmodel error distribution. The R-estimators are numerically illustrated and compared with the LSE and L-1 estimators in this situation.
Monthly seasonally adjusted temperatures above latitude 45 degrees N were investigated from January 1973 to November 2013. The study area was divided into 69 sub-regions of similar size each in the shape of an igloo b...
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Monthly seasonally adjusted temperatures above latitude 45 degrees N were investigated from January 1973 to November 2013. The study area was divided into 69 sub-regions of similar size each in the shape of an igloo brick. The data were filtered with a second-order autoregressive process to remove autocorrelation. Two sub-regions did not have sufficient data due to substantial numbers of missing values. Factor analysis was then applied to the remaining 67 sub-regions and was used to classify regions with similar temperature changes. As a result, 63 sub-regions could be classified based on 12 factors but 4 sub-regions could not be grouped due to uniqueness. The temperatures for each group of sub-regions were found to increase during 1973-2013. The largest temperature increases of 0.19 degrees C/decade were found in northern and southern Siberia and part of the Arctic Ocean. In northern Canada, Alaska, the northern Pacific Ocean and eastern Siberia the temperatures increased by at least 0.16 degrees C/decade. In Iceland, Norway, Sweden and part of the Pacific and Arctic Oceans the temperature increased by around 0.15 degrees C/decade. In northeastern Canada, Greenland and its surrounding Atlantic Ocean and the Arctic Ocean the temperature increased by about 0.15 degrees C/decade.
This work aims at estimating inverse autocovariance matrices of long memory processes admitting a linear representation. A modified Cholesky decomposition is used in conjunction with an increasing order autoregressive...
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This work aims at estimating inverse autocovariance matrices of long memory processes admitting a linear representation. A modified Cholesky decomposition is used in conjunction with an increasing order autoregressive model to achieve this goal. The spectral norm consistency of the proposed estimate is established. We then extend this result to linear regression models with long-memory time series errors. In particular, we show that when the objective is to consistently estimate the inverse autocovariance matrix of the error process, the same approach still works well if the estimated (by least squares) errors are used in place of the unobservable ones. Applications of this result to estimating unknown parameters in the aforementioned regressionmodel are also given. Finally, a simulation study is performed to illustrate our theoretical findings.
The aim of this study was to study the main determinants of soil dispersion, such as Na+, pH, kaolinite, illite and montmorillonite clay content, by grey relational analysis. Multiple linearregression and partial lea...
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The aim of this study was to study the main determinants of soil dispersion, such as Na+, pH, kaolinite, illite and montmorillonite clay content, by grey relational analysis. Multiple linearregression and partial least squares regression were applied to establish correlations between soil dispersion and its main determinants. Raw spectra (or raw reflectance;RR) of 50 soil samples was measured between 350 and 2500 nm. Continuum-removal (CR) spectral reflectance was calculated. Relationships of Na+, pH, kaolinite, illite and montmorillonite clay content with spectral reflectance were constructed to find sensitive spectral bands and the best spectral indices. Multiple stepwise regression was used to calculate five determinants from hyperspectral reflectance. models were evaluated by the determinant (R-2), root mean square error, and relative root mean square error. Sensitive wavelengths were chosen based on the highest positive and negative correlations between five determinants and RR or CR reflectance. Results indicated that with the highest R-2 (0.686), the multiple linear regression model was the best for the prediction of soil dispersion using spectral reflectance. According to R-2 values, CR reflectance was the best predictor of Na+ (0.725), pH (0.852), kaolinite (0.909), illite (0.923) and montmorillonite (0.876). In conclusion, the methods examined here offered quick and novel means of predicting soil dispersion using spectral reflectance data.
Background: Auxin is a major phytohormone involved in many developmental processes by controlling gene expression through a network of transcriptional regulators. In Arabidopsis thaliana, the auxin signalling network ...
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Background: Auxin is a major phytohormone involved in many developmental processes by controlling gene expression through a network of transcriptional regulators. In Arabidopsis thaliana, the auxin signalling network is made of 52 potentially interacting transcriptional regulators, activating or repressing gene expression. All the possible interactions were tested in two-way yeast-2-hybrid experiments. Our objective was to characterise this auxin signalling network and to quantify the influence of the dimerisation sequence dissimilarities on the interaction between transcriptional regulators. Results: We applied model-based graph clustering methods relying on connectivity profiles between transcriptional regulators. Incorporating dimerisation sequence dissimilarities as explanatory variables, we modelled their influence on the auxin network topology using mixture of linearmodels for random graphs. Our results provide evidence that the network can be simplified into four groups, three of them being closely related to biological groups. We found that these groups behave differently, depending on their dimerisation sequence dissimilarities, and that the two dimerisation sub-domains might play different roles. Conclusions: We propose here the first pipeline of statistical methods combining yeast-2-hybrid data and protein sequence dissimilarities for analysing protein-protein interactions. We unveil using this pipeline of analysis the transcriptional regulator interaction modes.
The problem of convergence of moments of a sequence of random variables to the moments of its asymptotic distribution is important in many applications. These include the determination of the optimal training sample s...
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The problem of convergence of moments of a sequence of random variables to the moments of its asymptotic distribution is important in many applications. These include the determination of the optimal training sample size in the cross-validation estimation of the generalization error of computer algorithms, and in the construction of graphical methods for studying dependence patterns between two biomarkers. In this paper, we prove the uniform integrability of the ordinary least squares estimators of a linear regression model, under suitable assumptions on the design matrix and the moments of the errors. Further, we prove the convergence of the moments of the estimators to the corresponding moments of their asymptotic distribution, and study the rate of the moment convergence. The canonical central limit theorem corresponds to the simplest linear regression model. We investigate the rate of the moment convergence in canonical central limit theorem proving a sharp improvement of von Bahr's (Ann Math Stat 36:808-818, 1965) theorem.
The Internet has become an integral part of our everyday life. Unfortunately, not all of us are equally aware of the threats when we use online services. Naive users are generally less aware of security and privacy pr...
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ISBN:
(纸本)9781467388450
The Internet has become an integral part of our everyday life. Unfortunately, not all of us are equally aware of the threats when we use online services. Naive users are generally less aware of security and privacy practices on the Internet and are susceptible to online predators. In this paper, we present a behavioral analysis of Internet users and their susceptibility to online malpractices. We have considered the dataset from the Global Internet User Survey for 10789 respondents to perform a security-oriented statistical analysis of correlated user behavior. We constructed logistic regressionmodels to analyze the statistical predictability of susceptible and not-so-susceptible identity theft victims based on their behavior and knowledge of security and privacy practices. We posit that such a study can be used to assess the vulnerability of Internet users and can hence be used to leverage institutional and personal safety on the Internet by promoting online security education, threat awareness, and guided Internet-safe behavior.
In regular linear regression model with the type II constraints the unobservable parameters in the constraints can be estimated by the BLUE of the observable parameters. The BLUE respects the constraints. If the estim...
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In regular linear regression model with the type II constraints the unobservable parameters in the constraints can be estimated by the BLUE of the observable parameters. The BLUE respects the constraints. If the estimator of the observable parameters which is the BLUE in the model without constraints is used, then the estimator of the unobservable parameters is the same. A problem is whether this is valid in the case of a singular model.
The Evaluation of a summary's linguistic quality is a difficult task because several linguistic aspects (e.g. grammaticality, coherence, etc.) must be verified to ensure the well formedness of a text's summary...
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ISBN:
(纸本)9783319417547;9783319417530
The Evaluation of a summary's linguistic quality is a difficult task because several linguistic aspects (e.g. grammaticality, coherence, etc.) must be verified to ensure the well formedness of a text's summary. In this paper, we report the result of combining "Adapted ROUGE" scores and linguistic quality features to assess linguistic quality. We build and evaluate models for predicting the manual linguistic quality score using linearregression. We construct models for evaluating the quality of each text summary (summary level evaluation) and of each summarizing system (system level evaluation). We assess the performance of a summarizing system using the quality of a set of summaries generated by the system. All models are evaluated using the Pearson correlation and the Root mean squared error.
Developing organizations are spends lots of money to finding the Errors and bugs. In this article, an application of defects removal effectiveness to improve the software quality and fault prone analysis, methods are ...
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Developing organizations are spends lots of money to finding the Errors and bugs. In this article, an application of defects removal effectiveness to improve the software quality and fault prone analysis, methods are finding the solution of parameters in linear regression models with cost estimating method. It describes the approach of quantitative quality management through defect removal effectiveness and statistical process control of cost analysis with historical project data. Software quality is going continuously monetary benefit to perform well management planning, and achieve a new height. In this methodology, Software quality model can make timely predictions of reliability indications;it's enabling to improve software development processes by target reducing the estimated cost for software products and improve the techniques for more effectively and efficiently. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://***/licenses/by-nc-nd/4.0/).
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