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Students Perceptions Towards Industrial Attachment in Kumasi: An Ordinal logistic Approach
Maxwell B. Asare,
Robert K. Antwiadjei-Manu,
Kofi A. Ababio
Issue:
Volume 3, Issue 6, December 2015
Pages:
275-280
Received:
1 September 2015
Accepted:
19 September 2015
Published:
16 October 2015
Abstract: The association of four ordered categories of student’s perceptions towards challenges in industrial attachment program with socio-demographic characteristics is researched in this study. The ordered nature of responses motivated the use of ordinal logistic model. With the aid of questionnaire, data were gathered from students who were serving in various institutions within the Kumasi metropolis of Ghana. We developed a latent variable model from the ordinal logistic model for thresholds of the categories of student’s perceptions towards industrial attachment. Gender and marital status showed negative relationship on students’ perception about industrial attachment. However, for place of attachment, supervisor and office space positive associations were found. We evaluated the validity of our model using the assumption of parallel lines.
Abstract: The association of four ordered categories of student’s perceptions towards challenges in industrial attachment program with socio-demographic characteristics is researched in this study. The ordered nature of responses motivated the use of ordinal logistic model. With the aid of questionnaire, data were gathered from students who were serving in v...
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Imputation of Missing Values for BL (P,0,P,P) Models with Normally Distributed Innovations
Issue:
Volume 3, Issue 6, December 2015
Pages:
234-242
Received:
4 October 2015
Accepted:
21 October 2015
Published:
30 October 2015
Abstract: This study derived estimates of missing values for bilinear time series models BL (p, 0, p, p) with normally distributed innovations by minimizing the h-steps-ahead dispersion error. For comparison purposes, missing value estimates based on artificial neural network (ANN) and exponential smoothing (EXP) techniques were also obtained. Simulated data was used in the study. 100 samples of size 500 each were generated for bilinear time series models BL (1, 0, 1, 1) using the R-statistical software. In each sample, artificial missing observations were created at data positions 48, 293 and 496 and estimated using these methods. The performance criteria used to ascertain the efficiency of these estimates were the mean absolute deviation (MAD) and mean squared error (MSE). The study found that optimal linear estimates were the most efficient estimates for estimating missing values for BL (p, 0, p, p). The study recommends OLE estimates for estimating missing values for bilinear time series data with normally distributed innovations.
Abstract: This study derived estimates of missing values for bilinear time series models BL (p, 0, p, p) with normally distributed innovations by minimizing the h-steps-ahead dispersion error. For comparison purposes, missing value estimates based on artificial neural network (ANN) and exponential smoothing (EXP) techniques were also obtained. Simulated data...
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Incorporating Survey Weights into Binary and Multinomial Logistic Regression Models
Kennedy Sakaya Barasa,
Chris Muchwanju
Issue:
Volume 3, Issue 6, December 2015
Pages:
243-249
Received:
29 July 2015
Accepted:
4 August 2015
Published:
19 November 2015
Abstract: Since sampling weights are not simply equal to the reciprocal of selection probabilities its always challenging to incorporate survey weights into likelihood-based analysis. These weights are always adjusted for various characteristics. In cases where logistic regression model is used to predict categorical outcomes with survey data, the sampling weights should be considered if the sampling design does not give each individual an equal chance of being selected in the sample. The weights are rescaled to sum to an equivalent sample size since original weights have small variances. The new weights are called the adjusted weights. Quasi-likelihood maximization is the method that is used to make estimation with the adjusted weights but the other new method that can be created is correct likelihood for logistic regression which included the adjusted weights. Adjusted weights are further used to adjust for both covariates and intercepts when the correct likelihood method was used. We also looked at the differences and similarities between the two methods. Analysis: Both binary logistic regression model and multinomial logistic regression model were used in parameter estimation and we applied the methods to body mass index data from Nairobi Hospital, which is in Nairobi County where a sample of 265 was used. R-software Version 3.0.2 was used in the analysis. Conclusion: The results from the study showed that there were some similarities and differences between the quasi-likelihood and correct likelihood methods in parameter estimates, standard errors and statistical p-values.
Abstract: Since sampling weights are not simply equal to the reciprocal of selection probabilities its always challenging to incorporate survey weights into likelihood-based analysis. These weights are always adjusted for various characteristics. In cases where logistic regression model is used to predict categorical outcomes with survey data, the sampling w...
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Statistical Analysis of Road Traffic Car Accident in Dire Dawa Administrative City, Eastern Ethiopia
Belachew Melese Hunde,
Zeleke Dutamo Aged
Issue:
Volume 3, Issue 6, December 2015
Pages:
250-256
Received:
13 September 2015
Accepted:
29 September 2015
Published:
3 December 2015
Abstract: Road traffic accidents (RTAs) have turned out to be a huge global public health and development problem. Dire Dawa City one of the federal states in North East Ethiopia has a high rate of accidents and deaths in relation to number of vehicles on the road. Realizing the need to establish baseline information on RTAs, the present study was conducted in Dire Dawa city under the jurisdiction of Dire Dawa Police Station, Dire Dawa, Ethiopia. Complete Road traffic car accident data of the year 2009 - 2013 from police records of Dire Dawa city Police station were studied. Data can be analyzed by using SPSS version 20.0 and MINITAB version 13.1 software. Data interpretation was done using descriptive statistics, two t-test comparison, chi-square test of independence, analysis of variance (one-way and two-way), and design of factorial experiment. The finding of this paper showed that the main cause of car accident is drivers. About 80% of car accident is resulted from the driver fault. Among the accident that resulted from the driver fault, not given priority for pedestrian contain the first position. Other factor like poor road condition, poor car condition, the absence of knowledge in traffic system, lack of ambulance and poor medical treatment are other cause and condition that increase the severity of the incident. Generally, the occurrence of car accident problem depends on defect on human factor, vehicle characteristics, road characteristics and environmental condition. The age of driver had also a significant impact on the occurrence of traffic accidents. Accidents were also highly depending on environmental factor like weather condition, type of road surface, condition of the road and joint road shape.
Abstract: Road traffic accidents (RTAs) have turned out to be a huge global public health and development problem. Dire Dawa City one of the federal states in North East Ethiopia has a high rate of accidents and deaths in relation to number of vehicles on the road. Realizing the need to establish baseline information on RTAs, the present study was conducted ...
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Holt-Winters Forecasting Method That Takes into Account the Effect of Eid
Bustami,
Hadi Irawansyah,
M. D. H. Gamal
Issue:
Volume 3, Issue 6, December 2015
Pages:
257-262
Received:
13 November 2015
Accepted:
25 November 2015
Published:
14 December 2015
Abstract: This paper discusses the Holt-Winters forecasting method that takes into account the effect of Eid. This method is used to predict the total domestic passengers departing in five major ports in Indonesia. Then a comparison is carried out between Holt-Winters method and Holt-Winters method that takes into account the effect of Eid. The comparison is done by comparing the mean square error obtained by both methods of forecasting, and it shows that the modified method provides better forcasting results.
Abstract: This paper discusses the Holt-Winters forecasting method that takes into account the effect of Eid. This method is used to predict the total domestic passengers departing in five major ports in Indonesia. Then a comparison is carried out between Holt-Winters method and Holt-Winters method that takes into account the effect of Eid. The comparison is...
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Application of Latin Hypercube Sampling Based Kriging Surrogate Models in Reliability Assessment
Liu Chu,
Eduardo Souza De Cursi,
Abdelkhalak El Hami,
Mohamed Eid
Issue:
Volume 3, Issue 6, December 2015
Pages:
263-274
Received:
28 November 2015
Accepted:
5 December 2015
Published:
22 December 2015
Abstract: Reliability assessment is one of the necessary and critical parts in structural design under uncertainties. The methods for structural reliability assessment aim at evaluating the probability of limit state by considering the fluctuation of acting loads, variation of structural component or system, and complexity of operating environment. Latin Hypercube sampling (LHS) method as advanced Monte Carlo simulation (MCS) has higher efficiency in sampling. It will be chosen and applied in this paper in order to obtain an effective database for building Kriging surrogate models. In this paper, we propose an effective method to have reliability assessment by Latin Hypercube sampling based Kriging surrogate models. This method keeps the certain level of accuracy in prediction of the response of a structural finite element model or other explicit mathematical functions.
Abstract: Reliability assessment is one of the necessary and critical parts in structural design under uncertainties. The methods for structural reliability assessment aim at evaluating the probability of limit state by considering the fluctuation of acting loads, variation of structural component or system, and complexity of operating environment. Latin Hyp...
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An Efficient Class of Exponential Chain Ratio Type Estimator for Finite Population Mean in Double Sampling
Issue:
Volume 3, Issue 6, December 2015
Pages:
281-287
Received:
12 October 2015
Accepted:
4 November 2015
Published:
25 December 2015
Abstract: This paper presents a class of exponential chain ratio type estimator in double sampling for estimating finite population mean of the study variable, when the information on another additional auxiliary variable is known along with the main auxiliary variable. The property of proposed class of estimator has been studied. Comparison has been made with other competitive estimators. The proposed estimator is found to be more efficient both theoretically and empirically.
Abstract: This paper presents a class of exponential chain ratio type estimator in double sampling for estimating finite population mean of the study variable, when the information on another additional auxiliary variable is known along with the main auxiliary variable. The property of proposed class of estimator has been studied. Comparison has been made wi...
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Two Factor Data Analysis with Unequal Cell Frequencies and Interaction
Chinwendu Alice Uzuke,
Ikewelugo Cyprian Anene Oyeka,
Happiness Onyebuchi Obiora-Ilouno
Issue:
Volume 3, Issue 6, December 2015
Pages:
288-292
Received:
18 November 2015
Accepted:
5 December 2015
Published:
25 December 2015
Abstract: This paper proposes a non parametric method for two factor data analysis with unequal cell frequencies and interaction. Chi-square test statistic was developed for testing the null hypothesis of no treatment effect and interaction between factor A and factor B. The proposed methods are illustrated with some data and compared with the usual unweighted mean method. The result showed that the proposed method is more powerful than the method of unweighted mean.
Abstract: This paper proposes a non parametric method for two factor data analysis with unequal cell frequencies and interaction. Chi-square test statistic was developed for testing the null hypothesis of no treatment effect and interaction between factor A and factor B. The proposed methods are illustrated with some data and compared with the usual unweight...
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The Optimal Estimation of Lasso
Issue:
Volume 3, Issue 6, December 2015
Pages:
293-297
Received:
30 December 2015
Published:
30 December 2015
Abstract: The estimation of lasso is important problem of high dimensional data; the optimal estimation’s formula of lasso is unsolved riddle of high dimensional data. In order to solve this problem, we give the structure of lasso estimation by using mathematical method in the orthogonal design. The optimal estimation’s formula of lasso is solved in the orthogonal design, it is pointed out that there is a gradual process of dimension reduction by using method of lasso.
Abstract: The estimation of lasso is important problem of high dimensional data; the optimal estimation’s formula of lasso is unsolved riddle of high dimensional data. In order to solve this problem, we give the structure of lasso estimation by using mathematical method in the orthogonal design. The optimal estimation’s formula of lasso is solved in the orth...
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Effect of Vocabulary Building Instruction on Technical School Students’ Achievement in Algebraic Word Problems in Benue State, Nigeria
Clement Onwu Iji,
Godwin Aôndohemba Fiase,
Odihi Adikwu
Issue:
Volume 3, Issue 6, December 2015
Pages:
298-305
Received:
13 December 2015
Accepted:
20 December 2015
Published:
30 December 2015
Abstract: Mathematics is used in everyday life, be it social, economic, arts, science or technology. However, empirical evidence shows that students achieve poorly in the subject at School Certificate level especially in the algebraic expression. Research findings have indicated that this low achievement may be attributed to inappropriate pedagogies used by teachers and this necessitated this study. The study made use of a quasi-experimental design of the non-equivalent control group. The sample of 604 part II students was drawn from technical schools in educational zones A and B using multistage sampling technique. Three research questions were raised and three hypotheses were formulated and tested at 0.05 level of significance. The instrument- AWPAT whose reliability was established using Cronbach Alpha to be 0.722 was used for data collection. Data collected was analyzed using mean and standard deviations to answer research questions and analysis of covariance (ANCOVA) to test the hypotheses. The result showed that the Vocabulary Building Instruction method used has enhanced students’ achievement significantly. The gap between male and female students on achievement was also minimized. Based on the findings of the study, technical school teachers were recommended to adopt method not only for algebra but other difficult topics in mathematics.
Abstract: Mathematics is used in everyday life, be it social, economic, arts, science or technology. However, empirical evidence shows that students achieve poorly in the subject at School Certificate level especially in the algebraic expression. Research findings have indicated that this low achievement may be attributed to inappropriate pedagogies used by ...
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