Abstract: Control charts are considered as powerful tools in detecting any shift in a process. Usually, the Shewhart control chart is used when data follows the symmetrical property of a normal distribution. In practice, the data from the industry may follow a non-symmetrical distribution or an unknown distribution. The average run length (ARL) is a significant measure to assess the performance of the control chart. The ARL may mislead when the statistic is computed from an asymmetric distri...
Abstract . Introduction In this research life time distribution known as exponentiated inverse Rayleigh distribution (EIRD) was developed and it can be used in reliability estimation and statistical quality control techniques. Te Rayleigh distribution is originated from two parameter Weibull distribution and it is appropriate model for life-testing studies. It can be shown by transformation of random variable that if the random variable (r. v) T has Rayleigh distribution, then the r. v. � =...
Abstract In this manuscript, a control chart is designed for two-piece normal distribution using repetitive sampling. The necessary measures to determine the average run lengths for in control and out-of-control process are given. The average run lengths are presented for various specified parameters and shift constants. The efficiency of the proposed chart is compared with the existing control chart using single sampling. The application of the proposed chart is given with the help of an ex...
Abstract Evaluation of customer satisfaction differs from one study to another. Studies have been differing with their focus and coverage. Most of studies focused on evaluating factors influencing customer satisfaction or associate customer satisfaction and quality of services. This paper used logistic regression to develop customer satisfaction model for Precision Air. Five dimensions or variables have been considered: on time performance; aircraft safety; schedule integrity; on board servi...
ABSTRACT In this manuscript, a group acceptance sampling plan (GASP) is developed when the lifetime of the items follows odd generalized exponential log-logistic distribution (OGELLD), the multiple number of items as a group can be tested simultaneously in a tester. The design parameters such as the minimum group size and the acceptance number are derived when the consumer’s risk and the test termination time are specified. The operating characteristic (OC) function values are calculated (...
Abstract Tuberculosis (TB) is one of the most important public health problems in Tanzania and was declared as a national public health emergency in 2006. Community and individual knowledge and perceptions are critical factors in the control of the disease. The objective of this study was to analyze the knowledge and perception on the transmission of TB in Tanzania. Multinomial Logistic Regression analysis was considered in order to quantify the impact of knowledge and perception on TB. The ...
Abstract: In this paper, acceptance sampling plans are developed for the odds exponential log logistic distribution (OELLD) introduced by Rosaiah et al. [1] based on lifetime percentiles when the life test is truncated at a predetermined time. The minimum sample size necessary to ensure the specified lifetime percentile is obtained under a given customer’s risk. The operating characteristic values of the sampling plans as well as the producer’s risk are presented. One example with real d...
Abstract A multicomponent system of k components with independent and identically distributed random strengths X1, X2, . . . Xk , with each component undergoing random stress, is in working condition if and only if at least s out of k strengths exceed the subjected stress. Reliability is measured while strength and stress are obtained through a process following an exponentiated moment-based exponential distribution with different shape parameters. Reliability is gauged from the samples usin...
Binary response analysis is modeled when the response variable is nominal and as such violates the use of the ordinary linear regression model. This paper utilizes the classical approach to fit a categorical response regression model using the logit, probit. loglog and the complementary loglog (Cloglog) link functions under symmetric and asymmetric assumptions. It is captured in past studies that we can only make comparisons between these link functions when n is large say (n > 1000), In ...
Control chart is a useful technique which helps in detecting out of control signal in a process and it can either be a memory-type or memory-less control chart. This work is focused on evaluating the monthly incidence of diabetic disease using four univariate memory-type control charts. In this study we evaluated the average run length (ARL) properties of the memory-type control charts by adjusting the ARL value’s determinant parameters in each control charts, and the ARL value was set to...
Temperature is the coldness and hotness of the body and its unit is measured in Celsius. The data used for this research work is the average monthly temperature of Dhahran city which is located in the Kingdom of Saudi Arabia. The data range is from 1951 to 2010, and sample data of 1951 to 2008 was used for the estimation to choose the best model and the sample data from 2009 through 2010 was left for the forecast. Different models were tried but ARIMA (2, 1, 1) (0, 1, 1)12 is selected...
Abstract This paper attempts to evaluate the application of randomized complete block design (RCBD) model in improving crop production. Data for the study was sourced from an experiment that lasted for three weeks. The data were analyzed using SPSS package. After exploring the concept of the RCBD technique, the response of the soil nutrient to the treatment of the various manure types revealed that, there was a significant difference on crop yield with respect to the type of manure tre...
Abstract The current fertility rate(FR) reporting in developing and under developed countries of the globe has drawn the attention of national and demographic planners in seeking for solution to reduce the population growth and its attendant global consequences. It is in this light that this study seeks to determine some significant demographic characterization responsible for influencing fertility behavior and differentials. Using a random sample of 570 mothers both from a rural and urban e...
Abstract This study examined the use of acceptance sampling technique as an efficient tool for quality assurance in deciding whether a given lot of product is to be accepted or rejected in the market. This study designed two single sampling plans with a sample size of 125 from a lot of size 1350 bread loaves and an allowable number of defectives as 4 and 6 (i.e. c=4 and 6). The result indicated that the probability of rejecting the manufacturers’ product of good quality by the consumers is...