Onemust interact with a specific webpage or website in order to use the Internet for communication,teamwork,and other productive activities.However,because phishing websites look benign and not all website visitors ha...Onemust interact with a specific webpage or website in order to use the Internet for communication,teamwork,and other productive activities.However,because phishing websites look benign and not all website visitors have the same knowledge and skills to inspect the trustworthiness of visited websites,they are tricked into disclosing sensitive information and making them vulnerable to malicious software attacks like ransomware.It is impossible to stop attackers fromcreating phishingwebsites,which is one of the core challenges in combating them.However,this threat can be alleviated by detecting a specific website as phishing and alerting online users to take the necessary precautions before handing over sensitive information.In this study,five machine learning(ML)and DL algorithms—cat-boost(CATB),gradient boost(GB),random forest(RF),multilayer perceptron(MLP),and deep neural network(DNN)—were tested with three different reputable datasets and two useful feature selection techniques,to assess the scalability and consistency of each classifier’s performance on varied dataset sizes.The experimental findings reveal that the CATB classifier achieved the best accuracy across all datasets(DS-1,DS-2,and DS-3)with respective values of 97.9%,95.73%,and 98.83%.The GB classifier achieved the second-best accuracy across all datasets(DS-1,DS-2,and DS-3)with respective values of 97.16%,95.18%,and 98.58%.MLP achieved the best computational time across all datasets(DS-1,DS-2,and DS-3)with respective values of 2,7,and 3 seconds despite scoring the lowest accuracy across all datasets.展开更多
In the case of comparison between samples with unequal replications [n1 # n2 # n3 # ... # nk], the statistician should use LSD (Least Significant Difference) many times to achieve these comparisons, this method consum...In the case of comparison between samples with unequal replications [n1 # n2 # n3 # ... # nk], the statistician should use LSD (Least Significant Difference) many times to achieve these comparisons, this method consumes more time and effort. The purpose of this research is to find out a new method to do easy and reliable comparison between population means when the experiment or data involving different numbers of replications. In order to do this, a new formula was designed;the aim of this new formula is to develop the multiple comparisons into one step instead of doing it with many steps that consume more effort and time. In this work, the researcher used the mean of the replication number in the LDS formula instead of doing the calculation many times for each two means. The results of this study found that the new formula give similar results for multiple comparisons with minimal effort. It was concluded that the new formula (named Al-fahham’s Formula) achieves the same results with less time and efforts. It was recommended that Al-fahham’s Formula can be approved in the statistical textbooks and procedures.展开更多
In this study, series of hydroxyapatites containing Mg2+ and?CO2-3 are prepared by the precipitation method with independently varying concentrations of?CO2-3 and Mg2+. All the compounds are characterized by infrared ...In this study, series of hydroxyapatites containing Mg2+ and?CO2-3 are prepared by the precipitation method with independently varying concentrations of?CO2-3 and Mg2+. All the compounds are characterized by infrared spectra (IR);powder X-ray diffraction (PXRD) and elemental analysis. The physical analysis results show that the prepared compounds are pure B-type carbonate apatite. The presence of Mg2+ and?CO2-3 in the apatite cause the following effects on its physical properties: a decrease in a-dimension but no changes in c-dimension and a decrease in crystallinity as shown in XDR patterns and IR spectra. The results of the chemical analysis allow us to predict the predominant substitution mechanisms for the CO2-3 and the Mg2+ incorporations in the calcium hydroxyapatites and to calculate their relative contributions x, y and z. (II);?? 2. (IV);?? (V). Statistical studies of the results “multiple linear regression, analysis of variance (ANOVA) and t-test of the regression coefficients” allow us to determine and to test the mathematical model proposed. Finally, the present study makes it possible to write the general formula for these com-pounds.展开更多
Linear mixed effects models with general skew normal-symmetric (SNS) error are considered and several properties of the SNS distributions are obtained. Under the SNS settings, ANOVA-type estimates of variance compon...Linear mixed effects models with general skew normal-symmetric (SNS) error are considered and several properties of the SNS distributions are obtained. Under the SNS settings, ANOVA-type estimates of variance components in the model are unbiased, the ANOVA-type F-tests are exact F-tests in SNS setting, and the exact confidence intervals for fixed effects are constructed. Also the power of ANOVA-type F-tests for components are free of the skewing function if the random effects normally distributed. For illustration of the main results, simulation studies on the robustness of the models are given by comparisons of multivariate skew-normal, multivariate skew normal-Laplace, multivariate skew normal-uniform, multivariate skew normal-symmetric, and multivariate normal distributed errors. A real example is provided for the illustration of the proposed method.展开更多
Linear mixed effect models with skew-normal errors and distribution-free random effects are considered. The ANOVA-type F-tests are proposed to test the significance of random effects and the hypothesis on fixed effect...Linear mixed effect models with skew-normal errors and distribution-free random effects are considered. The ANOVA-type F-tests are proposed to test the significance of random effects and the hypothesis on fixed effects of interest, respectively. Both tests are proved to be exact F-tests under this model, and the exact confidence interval for fixed effects of interest is derived. Simulation results are given to study the powers of ANOVA-type tests.展开更多
文摘Onemust interact with a specific webpage or website in order to use the Internet for communication,teamwork,and other productive activities.However,because phishing websites look benign and not all website visitors have the same knowledge and skills to inspect the trustworthiness of visited websites,they are tricked into disclosing sensitive information and making them vulnerable to malicious software attacks like ransomware.It is impossible to stop attackers fromcreating phishingwebsites,which is one of the core challenges in combating them.However,this threat can be alleviated by detecting a specific website as phishing and alerting online users to take the necessary precautions before handing over sensitive information.In this study,five machine learning(ML)and DL algorithms—cat-boost(CATB),gradient boost(GB),random forest(RF),multilayer perceptron(MLP),and deep neural network(DNN)—were tested with three different reputable datasets and two useful feature selection techniques,to assess the scalability and consistency of each classifier’s performance on varied dataset sizes.The experimental findings reveal that the CATB classifier achieved the best accuracy across all datasets(DS-1,DS-2,and DS-3)with respective values of 97.9%,95.73%,and 98.83%.The GB classifier achieved the second-best accuracy across all datasets(DS-1,DS-2,and DS-3)with respective values of 97.16%,95.18%,and 98.58%.MLP achieved the best computational time across all datasets(DS-1,DS-2,and DS-3)with respective values of 2,7,and 3 seconds despite scoring the lowest accuracy across all datasets.
文摘In the case of comparison between samples with unequal replications [n1 # n2 # n3 # ... # nk], the statistician should use LSD (Least Significant Difference) many times to achieve these comparisons, this method consumes more time and effort. The purpose of this research is to find out a new method to do easy and reliable comparison between population means when the experiment or data involving different numbers of replications. In order to do this, a new formula was designed;the aim of this new formula is to develop the multiple comparisons into one step instead of doing it with many steps that consume more effort and time. In this work, the researcher used the mean of the replication number in the LDS formula instead of doing the calculation many times for each two means. The results of this study found that the new formula give similar results for multiple comparisons with minimal effort. It was concluded that the new formula (named Al-fahham’s Formula) achieves the same results with less time and efforts. It was recommended that Al-fahham’s Formula can be approved in the statistical textbooks and procedures.
文摘In this study, series of hydroxyapatites containing Mg2+ and?CO2-3 are prepared by the precipitation method with independently varying concentrations of?CO2-3 and Mg2+. All the compounds are characterized by infrared spectra (IR);powder X-ray diffraction (PXRD) and elemental analysis. The physical analysis results show that the prepared compounds are pure B-type carbonate apatite. The presence of Mg2+ and?CO2-3 in the apatite cause the following effects on its physical properties: a decrease in a-dimension but no changes in c-dimension and a decrease in crystallinity as shown in XDR patterns and IR spectra. The results of the chemical analysis allow us to predict the predominant substitution mechanisms for the CO2-3 and the Mg2+ incorporations in the calcium hydroxyapatites and to calculate their relative contributions x, y and z. (II);?? 2. (IV);?? (V). Statistical studies of the results “multiple linear regression, analysis of variance (ANOVA) and t-test of the regression coefficients” allow us to determine and to test the mathematical model proposed. Finally, the present study makes it possible to write the general formula for these com-pounds.
基金The authors are grateful to the referees for their valuable suggestions which considerably improved the paper. This work was supported by the National Natural Science Foundation of China (Grant Nos. 11171011, 11471036), the Natural Science Foundation of Beijing (Grant No. 1132007), and Beijing Municipal Science and Technology Project (Grant No. km201410005011). Research of A. Liu was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) and the National Institutes of Health (NIH).
文摘Linear mixed effects models with general skew normal-symmetric (SNS) error are considered and several properties of the SNS distributions are obtained. Under the SNS settings, ANOVA-type estimates of variance components in the model are unbiased, the ANOVA-type F-tests are exact F-tests in SNS setting, and the exact confidence intervals for fixed effects are constructed. Also the power of ANOVA-type F-tests for components are free of the skewing function if the random effects normally distributed. For illustration of the main results, simulation studies on the robustness of the models are given by comparisons of multivariate skew-normal, multivariate skew normal-Laplace, multivariate skew normal-uniform, multivariate skew normal-symmetric, and multivariate normal distributed errors. A real example is provided for the illustration of the proposed method.
基金supported by the National Natural Science Foundation of China under Grant Nos.11171011 and 11471036the Natural Science Foundation of Beijing under Grant No.1132007Beijing Municipal Science and Technology Project under Grant No.km201410005011
文摘Linear mixed effect models with skew-normal errors and distribution-free random effects are considered. The ANOVA-type F-tests are proposed to test the significance of random effects and the hypothesis on fixed effects of interest, respectively. Both tests are proved to be exact F-tests under this model, and the exact confidence interval for fixed effects of interest is derived. Simulation results are given to study the powers of ANOVA-type tests.