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The Statistical Distribution and Determinants of Mother’s Age at First Birth
Logubayom Anuwoje Ida,
Luguterah Albert
Issue:
Volume 4, Issue 2, March 2015
Pages:
41-52
Received:
14 January 2015
Accepted:
6 February 2015
Published:
16 February 2015
Abstract: The age at which child bearing begins, influences the number of children a woman bears throughout her reproductive period in the absence of any active fertility control. This study employed both parametric and non-parametric survival analysis techniques, with a cohort of women within the reproductive age (15-49 years), to determine the statistical distribution of the age at first birth of a woman from her time of birth and identify the significant prognostic factors determining the timing of first birth of Ghanaian women. Using data from the Ghana Demographic and Health Survey (GDHS), the study fitted several parametric Accelerated Failure Time models, from which the best parametric distribution for age at first birth was selected. The results revealed that, the average age at first birth was about 20 years, with more than 87.4% of the women having giving birth before they attained 25 years of age. The age at first birth among the Ghanaian women was best modeled by the log-logistic model. By this model, the age at which a woman had her first birth was determined, at the 10% significance level, by her Age at first marriage, her Educational level, her Wealth Status and whether or not the women practiced family planning before their first birth.
Abstract: The age at which child bearing begins, influences the number of children a woman bears throughout her reproductive period in the absence of any active fertility control. This study employed both parametric and non-parametric survival analysis techniques, with a cohort of women within the reproductive age (15-49 years), to determine the statistical ...
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Optimal Replacement Age and Maintenance Cost: A Case Study
Nayeema Sultana,
Md. RezaulKarim
Issue:
Volume 4, Issue 2, March 2015
Pages:
53-57
Received:
21 February 2015
Accepted:
4 March 2015
Published:
14 March 2015
Abstract: Maintenance plays a very vital role throughout an equipment/system’s planned life-cycle. Maintenance costs contribute a major portion of the life cycle costs of an equipment or system. This paper analyzes a set of failure data of a particular type of battery that used in automobile and/or trailer and proposes the optimal maintenance age at which the non-failed battery be maintained. A 2-fold Weibull mixture distribution is selected as the suitable distribution for the lifetime of the battery. The Expectation-Maximization (EM) algorithm is applied to estimate the parameters of the mixture distribution. The research will be of interest for effective maintenance management to maintenance engineers and managers working in battery manufacturing industry, as well as customers and service providers.
Abstract: Maintenance plays a very vital role throughout an equipment/system’s planned life-cycle. Maintenance costs contribute a major portion of the life cycle costs of an equipment or system. This paper analyzes a set of failure data of a particular type of battery that used in automobile and/or trailer and proposes the optimal maintenance age at which th...
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Investigating of Turkey Champion Clubs’ Financial Performance Using Bootstrap and Jackknife Methods
Tolga Zaman,
Kamil Alakus,
Hasan Bulut
Issue:
Volume 4, Issue 2, March 2015
Pages:
58-63
Received:
16 February 2015
Accepted:
4 March 2015
Published:
19 March 2015
Abstract: This study attempts to investigate using bootstrap and jackknife methods how accurate Turkey’s teams, being champion since super league was established, use their financial expenditure for the scores when they were consecutively in league between 2006-2007 and 2013-2014 seasons. In this context, the champion clubs’ financial performance values said eight seasons were obtained by dividing clubs’ total expenditure in each season to scored total points in current season. Also, the results obtained by bootstrap and jackknife methods were compared on the basis of error mean square. Thus, it was judged that bootstrap method gives better results than jackknife method. All statistics of bootstrap and jackknife methods were calculated by the aid of the R packaged software. Turkey’s clubs which had championship: Besiktas, Bursaspor, Fenerbahçe, Galatasaray and Trabzonspor.
Abstract: This study attempts to investigate using bootstrap and jackknife methods how accurate Turkey’s teams, being champion since super league was established, use their financial expenditure for the scores when they were consecutively in league between 2006-2007 and 2013-2014 seasons. In this context, the champion clubs’ financial performance values said...
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Analysis of Fertility Pattern Through Mathematical Curves
Brijesh P. Singh,
Kushagra Gupta,
K. K. Singh
Issue:
Volume 4, Issue 2, March 2015
Pages:
64-70
Received:
13 February 2015
Accepted:
26 February 2015
Published:
21 March 2015
Abstract: The age-specific fertility curves normalized by total fertility can be considered as the density of the age at childbearing distribution. Generally the shape of age specific fertility rate changes from convex to concave after it reaches its maximum value. Proportion bearing children before age 35 may be interpreted as tempo of fertility and rest may be interpreted as excess fertility, which is risky for mother as well as child both. Thus, the purpose of this study is to observe the pattern of fertility over time and space keeping the above idea into consideration. To experience the modest change in fertility, the estimated total fertility rate, are computed for the data through simple mathematical model. For this purpose the secondary data on age-specific fertility rate and its forward and backward cumulative distributions have been considered. Also the validity of proposed models has been checked through appropriate technique.
Abstract: The age-specific fertility curves normalized by total fertility can be considered as the density of the age at childbearing distribution. Generally the shape of age specific fertility rate changes from convex to concave after it reaches its maximum value. Proportion bearing children before age 35 may be interpreted as tempo of fertility and rest ma...
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