by Adeboye Nureni Olawale and Ezekiel Imekela Donaldson
Original Research
That malaria contributes substantially to the poor health situation in Africa is an understatement. To help government in the continuous provision of necessary measures needful to curb increasing spread of the parasites, there is a need to build an appropriate time domain model which can be used to forecast the future rate of spread. As a result of this, ARIMA model was built for analyzing the secondary data collected on the incidence of malaria. It was discovered that the data was not stationary and stationarity was achieved through 2nd order differencing. The ACF and PACF of the differenced data suggested possible models for selection. AIC and MSE were used to select the models that really provided a best fit for the time series. From various ARIMA models generated, ARIMA model was found to best fit the malaria data. Ljung-Box test and Shapiro-Wilk test met all necessary conditions for independence and normality. The model was used for forecast and it was observed that there is going to be a steady increase in malaria prevalence.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 170-175. DOI: 10.12691/ajams-6-4-7
Pub. Date: September 03, 2018
11857 Views2606 Downloads
by Priyadarshani GDD and Sooriyarachchi MR
Original Research
Besides climate change impacts on water availability and hydrological risks, the consequences on water quality is just beginning to be studied. This research concerns the impacts of climate change on surface water quality through multilevel analysis. Multilevel modeling is a relatively new statistical technique in environmental science research, although its roots can be traced back to several other fields. The objective of this study was to evaluate the surface water quality, its spatial variation and its dependence on climatic parameters. The water quality data for seven parameters, namely Color, Turbidity, pH, Electrical Conductivity, Chloride, Total Alkalinity and Total Hardness collected from 2012 to 2014 from 68 locations around Sri Lanka was used for the analysis. These monthly water quality measurements had been made on two occasions nested within locations within districts and thus had a multilevel structure. Hence a multilevel regression model was adopted using the Bayesian Markov Chain Monte Carlo method. Since, neither of the 95% credible intervals for chemical composition (0.682, 4.945) and physical composition (0.203, 0.485) of water included the value zero, district level variances are significant. The chemical composition of water varies more with the districts compared to the physical composition of water. Several locations in Anuradhapura and Monaragala districts contributed to this significant difference in chemical composition and several locations in Ampara district presented a significant contribution to the difference in the physical composition as shown by the non-inclusion of the value zero in their individual 95% confidence bands. Further, it was observed that rain (P<0.01), temperature (P<0.01) and humidity (P<0.05) have an impact on both the chemical and physical composition of surface water. Source type (P<0.01) has an impact only on physical composition of water. The main conclusion of the study was that drinking water quality varied geographically and over time according to climatic conditions.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 158-169. DOI: 10.12691/ajams-6-4-6
Pub. Date: August 19, 2018
11477 Views1719 Downloads
by A.N.M. Rezaul Karim, S.M. Mostafa Kamal and Md. Rashedul Islam
Original Research
Objectives: Since the maternal health of the tribal women is a world concern, it involves our attention more to them as they are underprivileged people all over the globe. This issue sounds true in the Bangladesh perspective as well. Antenatal care (ANC) is the first flight of stairs to reach the peak of success for safe-motherhood. It represents a series of evaluations over time, which is not implemented appropriately due to different types of limitation and problems. The study aimed to delve into ANC practices and the factors associated with this practices among tribal women dwelling in the Chittagong Hill Tracts (CHT) of Bangladesh. Materials and Methods: The descriptive statistic was used to analyze frequency, percentage. Associations were evaluated through Chi-square tests, and a binary logistic regression model was used to explore factors related to the use of ANC services. This paper is based on a quantitative study. Result: The study exposes that one-third (29.9%) of the pregnant women wanted ANC from a trained doctor of which 13.5% of women met adequate antenatal care attendance and 16.4% initiated attendance within three months of the pregnancy. Multivariable logistic regression analyses indicate that socio-economic status, place of residence, women's education, distance to health facilities, family planning were considered as the main determinant to seek ANC. The level of significance was set at 10% level of significance. Conclusion: The findings of the study suggest that specific efforts are needed to advance socio-economic status of tribal people, increasing the educational level of women and their husbands, reducing the distance from a health center, and strengthening family planning program are needed.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 149-157. DOI: 10.12691/ajams-6-4-5
Pub. Date: August 13, 2018
7418 Views1528 Downloads1 Likes
by Vennila J and Devaraj Arumainayagam S
Original Research
A new sampling inspection system with normal single sampling plan and tightened double sampling plan is introduced. Advantages of this system are highlighted.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 141-148. DOI: 10.12691/ajams-6-4-4
Pub. Date: August 09, 2018
9886 Views1502 Downloads
by M. Koierng Meitei, Yumnam Rohen and R. S. Verma
Original Research
In this paper, we prove a common fixed point theorem for two pairs of weak compatible mappings of type (A) in Gb-metric space. Further our result is verified with the help of example.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 135-140. DOI: 10.12691/ajams-6-4-3
Pub. Date: August 01, 2018
7409 Views2094 Downloads
by Daniel Thoya, Antony Waititu, Thomas Magheto and Antony Ngunyi
Original Research
The purpose of this study was to evaluate the methods used to assess “optimism” in regression models. Particularly, focus was on the use of pseudo R2values of cox &snail and the Nagelkerke to identify the best statistic for measuring “optimism” in regression models, measure model performance and determine the relationship between “optimism” and over fitting. Different underlying data sets assume different models that fit their data accurately. However, the fitted regression models usually fit the data they are based on better than new data. This is what we call ‘optimism’. Specific focus will be on determining the best statistic for measuring optimism in regression models, assess model performance using ‘optimism’ through cross-validation and also determining the relationship between optimism and over fitting of regression models. The study focus on three models (Cox-regression, Logistic regression and Linear Regression) and bootstrap procedure was used.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 126-134. DOI: 10.12691/ajams-6-4-2
Pub. Date: July 20, 2018
5182 Views1538 Downloads
by Alayande Semiu Ayinla
Original Research
This paper resolves the conflicts that exist between various cointegration tests for cases when different tests for cointegration provide different answers under the same data set. The tests considered are, Augumented Dickey Fuller (ADF) test, Hansen Lc test, Johansen’s test, and Stock and Watson (SW) test. The Monte Carlo experiments conducted show that the Stock Watson and Johansen tests can be grouped together while ADF test significantly shows different performances from that of Hansen Lc test.
American Journal of Applied Mathematics and Statistics. 2018, 6(4), 121-125. DOI: 10.12691/ajams-6-4-1
Pub. Date: July 19, 2018
6868 Views1494 Downloads1 Likes