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"Analisis data lifetime sangat penting dalam berbagai bidang ilmu pengetahuan seperti biomedis, teknik, dan ilmu kemasyarakatan. Pemodelan data tersebut dilakukan dengan menggunakan fungsi hazard dari distribusi lifetime seperti distribusi eksponensial, Weibull, lognormal, dan juga gamma. Namun, keempat distribusi tersebut tidak dapat memodelkan fungsi hazard berbentuk bathtub. Padahal, fungsi hazard berbentuk bathtub adalah yang paling sering ditemukan dalam kehidupan nyata. Oleh karena itu, akan dibentuk distribusi generalized Lindley yang lebih fleksibel dalam memodelkan fungsi hazard. Distribusi tersebut merupakan perumuman dari distribusi Lindley dengan menggunakan transformasi exponentiation. Kemudian, karakteristik-karakteristik dari distribusi generalized Lindley juga akan ditelusuri. Selanjutnya, analisis bentuk dari fungsi hazard akan menunjukkan bahwa distribusi generalized Lindley dapat memodelkan data dengan fungsi hazard yang berbentuk monoton naik, monoton turun, dan juga bathtub. Setelah itu, penaksiran parameter distribusi generalized Lindley akan dilakukan dengan metode yang paling umum digunakan yaitu metode maximum likelihood. Simulasi dengan membangkitkan data menggunakan software juga akan dilakukan dengan bantuan metode Newton-Raphson untuk melihat penaksiran parameter dari distribusi generalized Lindley.

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Analysis of lifetime data is very important in various fields such as biomedical science, engineering, and social science. The modelling of lifetime data is done by using hazard function of lifetime distributions such as exponential, Weibull, lognormal, and gamma distribution. However, these four distributions cannot model data with bathtub-shaped hazard function even though it is the one mostly found in real life situation. Therefore, more flexible distribution called generalized Lindley distribution is introduced to model hazard function. The distribution is created by using transformation called exponentiation to generalize the Lindley distribution. Afterwards, some characteristics of generalized Lindley distribution will be discussed. Analysis of the hazard function will show that generalized Lindley distribution can models data with increasing, decreasing, and bathtub-shaped hazard function. In addition, parameter estimation of the distribution will be done by the usual method which is maximum likelihood estimation. Lastly, simulation using software-generated data will be displayed with help from Newton-Raphson numerical method to see the parameter estimation of generalized Lindley distribution."

"The first part of the book (basic methods) covers convergent and divergent series, Chebyshev expansions, numerical quadrature, and recurrence relations. Its focus is on the computation of special functions; however, it is suitable for general numerical courses. Pseudoalgorithms are given to help students write their own algorithms. In addition to these basic tools, the authors discuss other useful and efficient methods, such as methods for computing zeros of special functions, uniform asymptotic expansions, Pad approximations, and sequence transformations. The book also provides specific algorithms for computing several special functions (like Airy functions and parabolic cylinder functions, among others)."

"Analisis regresi digunakan untuk mengetahui hubungan antara satu variabel respon dan satu atau lebih variabel penjelas. Ketika variabel respon berupa data count yaitu data yang berupa bilangan bulat non-negatif, analisis regresi yang sering digunakan adalah analisis regresi Poisson. Pada regresi Poisson terdapat asumsi kesamaan nilai mean dengan nilai variansinya. Dalam data count sering didapati kondisi dimana nilai variansi lebih besar dari nilai meannya atau disebut overdispersi. Pada data yang overdispersi, regresi Poisson kurang tepat jika digunakan karena nilai standard error dari taksiran parameter yang dihasilkan akanunderestimate sehingga beresiko memberikan kesimpulan yang tidak tepat. Model regresi Poisson-Inverse Gaussian dapat digunakan pada data count yang overdispersi dan memiliki tail panjang. Penaksiran parameter model regresi Poisson-Inverse Gaussian menggunakan metode maksimum likelihood dan solusi dari fungsi log -likelihood-nya menggunakan pendekatan numerik yaitu Newton-Raphson. Uji kesesuaian model yang digunakan mencakup statistik pseudo R-Squared, uji rasio likelihood, dan Uji Wald.

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Regression analysis is used to investigate the relationship between one response variable and one or more regressor variables. If the response variable is count data, that has non negative integer value, the regression analysis that usually used is Poisson Regression. Poisson regression has an assumption that mean of response variable equal to its variance. On count data frequently found that the variance is greater than mean, or called overdispersion. On overdispersion case, poisson regression is inconvenient to used because it may underestimate the standard error of regression parameters and consequently it risk to give misleading inference. Poisson Inverse Gaussian regression model can be used on overdispersion and long tail count data. Parameter estimation of Poisson Inverse Gaussian Regression Model can be obtained through the maximum likelihood method and the solution of log likelihood function may be solved by using numerical method called Newton Raphson. Goodness of fit testing of this model includes pseudo R Squared, rasio likelihood test, and Wald test."