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Effects of Response Errors on Population Parameters in Double Sampling for Stratification
David Anekeya Alilah,
Robert Keli,
Harun Makwata,
James Kahiri,
Leo O. Odongo
Issue:
Volume 3, Issue 2, April 2015
Pages:
27-32
Received:
30 January 2015
Accepted:
19 February 2015
Published:
2 March 2015
Abstract: This study investigates the effects of response errors on population parameters obtained by double sampling for stratification at the interview and data processing level. Simulation study is carried out to investigate the effects of the response errors on these estimates. Finite population is generated using R-statistical package and study variables are investigated in the presence and absence of errors. The results obtained are compared. It is observed that, in the presence of response errors on the estimates results in underestimation of the population parameters.
Abstract: This study investigates the effects of response errors on population parameters obtained by double sampling for stratification at the interview and data processing level. Simulation study is carried out to investigate the effects of the response errors on these estimates. Finite population is generated using R-statistical package and study variable...
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A Study on a Tandem Stochastic Queueing Model with Parallel Phases and a Numerical Example
Vedat Sağlam,
Erdinç Yücesoy,
Murat Sağır,
Müjgan Zobu
Issue:
Volume 3, Issue 2, April 2015
Pages:
33-38
Received:
3 February 2015
Accepted:
19 February 2015
Published:
8 March 2015
Abstract: In this study a two stage queueing model is analyzed. At first stage there is a single server having exponential service time with parameter μ_1 and no waiting is allowed in front of this server. There are two parallel phase-type servers at second stage and these parallel servers have exponential service time with parameter μ_2. Arrivals to this system is Poisson with parameter λ. An arriving customer to this system has service if the server at first stage is available or leaves the system if the server is busy where the first loss occurs. After having service in first stage the customer proceeds to the second stage, if both of the phase-type parallel servers in second stage are available the customer chooses one of these servers with probability 0.50 or leaves the system if any of these servers in second stage is busy so the second loss occurs. A customer who has service at both stages leaves the system. The number of customers in this model is represented by a 3-diamensional Markov chain and Kolmogorov differential equations are obtained. After that mean number of customers and mean waiting time in the system is obtained by limit probabilities. We have shown that the customer numbers at first and second stages are dependent to each other. The numerical analysis of obtained performance measures are shown by a numeric example. Finally the graphs of loss probabilities and measure of performances given for some values of arrival rate λ and the service parameters.
Abstract: In this study a two stage queueing model is analyzed. At first stage there is a single server having exponential service time with parameter μ_1 and no waiting is allowed in front of this server. There are two parallel phase-type servers at second stage and these parallel servers have exponential service time with parameter μ_2. Arrivals to this sy...
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Determination of the Status of Utilization and Management Scenarios Bonito (Auxis rochei) Caught in the Talaud Waters North Sulawesi
John S. Kekenusa,
Marline S. Paendong,
Winsy Ch. D. Weku,
Sendy B. Rondonuwu
Issue:
Volume 3, Issue 2, April 2015
Pages:
39-46
Received:
12 January 2015
Accepted:
27 February 2015
Published:
10 March 2015
Abstract: Bonito (Auxis rochei), needs to be managed well because even as a renewable natural resource, but can undergo depletion or extinction. One of the approach in the management of fish resources is by modeling. The analysis was performed aiming to get the best estimate for the surplus production model to determine the maximum sustainable yields (MSY), utilization level, and effort levelof bonito.The data of catch and fishing effort bonito collected from the Marine and Fisheries Service of the Talaud Regency and the North Sulawesi Province. Best Surplus Production Model, which is used to assess the potential of bonito is Schaefer Model. Optimal effort (EMSY) of 8,489 trips per year, with catches of optimal CMSY 2,453.77 tons per year. The effort level for 2012 is 193.99%, which shows the inefficiency of effort, the utilization level of 94.86%, showing indicate will occur overfishing.
Abstract: Bonito (Auxis rochei), needs to be managed well because even as a renewable natural resource, but can undergo depletion or extinction. One of the approach in the management of fish resources is by modeling. The analysis was performed aiming to get the best estimate for the surplus production model to determine the maximum sustainable yields (MSY), ...
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Analysis of the Volatility of the Electricity Price in Kenya Using Autoregressive Integrated Moving Average Model
Mohammed Mustapha Wasseja,
Samwel N. Mwenda
Issue:
Volume 3, Issue 2, April 2015
Pages:
47-57
Received:
17 February 2015
Accepted:
4 March 2015
Published:
30 March 2015
Abstract: Electricity has proved to be a vital input to most developing economies. As the Kenyan government aims at transforming Kenya into a newly-industrialized and globally competitive, more energy is expected to be used in the commercial sector on the road to 2030. Therefore, modelling and forecasting of electricity costs in Kenya is of vital concern. In this study, the monthly costs of electricity using Autoregressive Integrated Moving Average models (ARIMA) were used so as to determine the most efficient and adequate model for analysing the volatility of the electricity cost in Kenya. Finally, the fitted ARIMA model was used to do an out-off-sample forecasting for electricity cost for September 2013 to August 2016. The forecasting values obtained indicated that the costs will rise initially but later adapt a decreasing trend. A better understanding of electricity cost trend in the small commercial sector will enhance the producers make informed decisions about their products as electricity is a major input in the sector. Also it will assist the government in making appropriate policy measures to maintain or even lowers the electricity cost.
Abstract: Electricity has proved to be a vital input to most developing economies. As the Kenyan government aims at transforming Kenya into a newly-industrialized and globally competitive, more energy is expected to be used in the commercial sector on the road to 2030. Therefore, modelling and forecasting of electricity costs in Kenya is of vital concern. In...
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On Convergence a Variation of the Converse of Fabry Gap Theorem
Molood Gorji,
Naser Abbasi
Issue:
Volume 3, Issue 2, April 2015
Pages:
58-62
Received:
8 March 2015
Accepted:
26 March 2015
Published:
3 April 2015
Abstract: In this article we give a variation of the converse of Fabry Gap theorem concerning the location of singularities of Taylor-Dirichlet series, on the boundary of convergence. whose circle of convergence is the unit circle and for which the unit circle is not the natural boundary.
