Penggunaan Pendekatan Sistem-S dan ESSYNS dalam Analisis Taburan Normal

The purpose of this paper is to illustrate the use of S-systems methodology and ESSYNS software in the area of computational statistics. First, we demonstrate how the densities are formulated as S-systems, then we derive representations for cumulatives and quantiles. Cumulatives are obtained with little extra effort and quantiles are readily calculated from the inverted S-system. These representations are then solved numerically using ESSYNS. The density and the cumulative curves for the normal distribution are generated for the values in the range (-3,3). The S-system method produces many quantiles in a single computer run. The use of S-system generalizations and approximation has shown to be a useful alternative method for analysing distributions

Statistical analysis of vehicle theft crime in Peninsular Malaysia using negative binomial regression model

The aim of this paper was to identify the determinants that influence vehicle theft by applying a negative binomial regression model. The identification of these determinants is very important to policy-makers, car-makers and car owners, as they can be used to establish practical steps for preventing or at least limiting vehicle thefts. In addition, this paper also proposed a crime mapping application that allows us to identify the most risky areas for vehicle theft. The results from this study can be utilized by local authorities as well as management of internal resource planning of insurance companies in planning effective strategies to reduce vehicle theft. Indirectly, this paper has built ingenuity by combining information obtained from the database of Jabatan Perangkaan Malaysia and insurance companies to pioneer the development of location map of vehicle theft in Malaysia

ANALISIS SIRI MASA ZARAH TERAMPAI (PM10) DI LEMBAH KLANG, MALAYSIA

Masalah pencemaran udara adalah suatu fenomenon yang sering dinyatakan pada masa kini, misalnya pencemaran udara di kawasan bandar di negara-negara Asian. Pencemaran udara merupakan suatu keadaan yang melibatkan kehadiran sebarang gas atau zarah yang bertoksik atau beradioaktif seperti karbon monoksida, nitrogen oksida, zarah terampai dan sebagainya ke dalam atmosfera, hal ini boleh memberi kesan berbahaya kepada tubuh manusia. Dalam kajian ini dibincangkan peramalan dan pengkajian trend data kepekatan zarah terampai (PM10) dengan menggunakan pendekatan Box-Jenkins, di empat kawasan, iaitu Kuala Lumpur, Shah Alam, Petaling Jaya dan Kajang. Data cerapan yang digunakan adalah data yang dikumpulkan secara purata harian dari bulan Januari 2007 hingga Disember 2007. Pendekatan Box-Jenkins terdiri daripada empat langkah asas, iaitu langkah pengecaman kasar, langkah penganggaran parameter, langkah penyemakan diagnostik dan peramalan. Hasil kajian ini menunjukkan bahawa keempat-empat kawasan mempunyai model yang sama, iaitu model AR(3) tanpa parameter φ2 . Kesamaan model yang diperoleh bagi keempat-empat kawasan pengamatan disebabkan keempat-empat kawasan tersebut merupakan kawasan yang kedudukannya saling berhampiran. Model ini digunakan untuk analisis selanjutnya, iaitu peramalan data masa akan datang. Kata kunci: Box Jenkins; autoregresi; purata bergerak; autoregresi dan purata bergerak; campuran autoregresi dan purata bergerak berintegras

Zero-inflated regression models with an application to vehicle theft count data

Poisson regression model has been widely used for modeling claim count data in actuarial and insurance literatures.However, in several cases, claim count data often have excessive number of zeros than are expected in the Poisson model. In that case the Poisson regression may underestimate the standard errors and giving misleading inference about the regression parameters. This paper aims to apply the zero-inflated regression models on vehicle theft crime data.These zero-inflation phenomenon is a very specific type of over dispersion and zero-inflated Poisson (ZIP) regression model has been suggested for handling zero-inflated data.If the crime count data continue to suggest additional over dispersion, the alternative models the zero-inflated negative binomial-1 (ZINB-1) and the zero-inflated negative binomial-2 (ZINB-2) will be fitted on the private car theft claim count data.In addition, two different forms of link function will be used in the fitting procedure of the zero-inflated regression models, producing different estimates for each model.The results of this study indicate that the ZINB-2 models is better compared to ZIP regression model for handling zero-inflated and additional overdispersed crime count data

Modelling for determination of fe uptake by Brassica chinensis Jusl var. parachinensis (Bailey) Tsen & Lee (Flowering White Cabbage)

The study was conducted to determine the best model suitable for the determination of ferrum uptake in Brassica chinensis (flowering white cabbage). A nonlinear regression model was selected to determine the amount of ferrum absorbed by each part of the Brassica chinensis plant namely the leaves, stems and roots. The Levenberg-Marquardt method was used to perform the nonlinear least square fit. This method employs information on the gradients and hence requires specification of the partial derivatives. A suitable model was obtained from the exponential regression model. The polynomial model was found to be appropriate for leaves, the mono-exponential model was suitable for stems and the simple exponential model for roots. The residual plots and the normal probability plots from each of the models indicated no substantial diagnostic problems, so it can be concluded that the polynomial and exponential regression models provide adequate fit to determine data on heavy metal uptake by the flowering white cabbage

Analisis siri masa zarah terampai (PM10) di Lembah Klang, Malaysia

Masalah pencemaran udara adalah suatu fenomenon yang sering dinyatakan pada masa kini,misalnya pencemaran udara di kawasan bandar di negara-negara Asian. Pencemaran udara merupakan suatu keadaan yang melibatkan kehadiran sebarang gas atau zarah yang bertoksik atau beradioaktif seperti karbon monoksida, nitrogen oksida, zarah terampai dan sebagainya ke dalam atmosfera, hal ini boleh memberi kesan berbahaya kepada tubuh manusia. Dalam kajian ini dibincangkan peramalan dan pengkajian trend data kepekatan zarah terampai (PM10) dengan menggunakan pendekatan Box-Jenkins, di empat kawasan, iaitu Kuala Lumpur, Shah Alam, Petaling Jaya dan Kajang. Data cerapan yang digunakan adalah data yang dikumpul secara purata harian dari bulan Januari 2007 hingga Disember 2007.Pendekatan Box-Jenkins terdiri daripada empat langkah asas, iaitu langkah pengecaman kasar,langkah penganggaran parameter, langkah penyemakan diagnostik dan peramalan. Hasil kajian ini menunjukkan bahawa keempat-empat kawasan mempunyai model yang sama, iaitu model AR(3) tanpa parameter 2 . Kesamaan model yang diperoleh bagi keempat-empat kawasan pengamatan disebabkan keempat-empat kawasan tersebut merupakan kawasan yang kedudukannya saling berhampiran. Model ini digunakan untuk analisis selanjutnya, iaitu peramalan data masa akan datang

Pemetaan kepekatan metana di Semenanjung Malaysia

Pemanasan global merupakan masalah persekitaran yang amat serius di negara maju dan juga di negara yang sedang membangun. Antara punca utamanya ialah peningkatan gas rumah hijau. Gas metana merupakan satu daripada gas rumah hijau yang berupaya memerangkap haba 21 kali ganda lebih berkesan berbanding dengan karbon dioksida. Objektif kajian ini adalah untuk membuat peta kepekatan gas metana di Semenanjung Malaysia, membandingkan perubahan kepekatan gas metana mengikut bulan dan menentukan lokasi yang mempunyai kepekatan metana yang tertinggi berdasarkan data tahun 2009. Hasil kajian ini menunjukkan lokasi kepekatan metana yang tertinggi adalah di utara negeri Perak; sekitar Klang di Selangor dan Pengerang di Johor. Kajian ini juga mendapati lokasi yang mempunyai kepekatan metana yang tinggi tidak banyak berubah mengikut masa

Persepsi ke atas penggunaan alat dan teknik kualiti terhadap prestasi kualiti dalam industri pembuatan

Penggunaan alat dan teknik kualiti adalah kaedah peningkatan kualiti yang digunakan untuk mengumpul dan menganalisis data secara sistematik. Dalam makalah ini, persepsi penggunaan alat dan teknik kualiti terhadap prestasi kualiti dalam industri pembuatan dikaji. Sampel kajian terdiri daripada 219 buah industri pembuatan merangkumi organisasi bersaiz kecil, sederhana dan besar yang beroperasi di negeri Selangor. Kajian ini menggunakan analisis lintasan dengan penganggaran kebolehjadian maksimum untuk menganggarkan hubungan dalam satu sistem persamaan struktur menggunakan perisian AMOS yang melibatkan 5 kriterium, iaitu alat kawalan proses statistik (KPS), alat pengurusan, teknik lanjutan, peningkatan kualiti dan prestasi kualiti. Hasil analisis lintasan menunjukkan pemberat regresi anggaran adalah bererti berdasarkan nilai-p (nilai-p < 0.05), iaitu perkaitan antara kriterium kajian adalah bererti secara statistik melainkan perkaitan antara alat pengurusan dengan peningkatan kualiti. Ringkasnya, model analisis lintasan adalah sah dari segi statistik dan mencapai indeks padanan yang baik dengan ujian Khi kuasa dua (χ2 (dk = 3) = 6.172, nilai-p = 0.082), CFI = 0.989, TLI = 0.963 dan RMSEA = 0.075. Kesimpulannya, kajian ini memberikan penunjuk awal terhadap pengukuran prestasi kualiti melalui penggunaan alat dan teknik kualiti khususnya dalam industri pembuatan

Kriteria pemilihan kakitangan akademik IPTS menggunakan teknik sentroid tertib pangkat

This study was carried out to determine the importance of each criterion and sub criteria that are considered during academic staff selection. This is a case study which was carried out from April to June 2005 at UNITEN, a private institution of higher education (PIHE) with university status. Interview was conducted with the human resource manager to find out about their academic staff selection procedure. Questionnaire was distributed to every decision maker (Dean, Deputy Dean, Head of Department) in academic staff selection. Ranking scale was used to rank the importance of the criteria and sub criteria. Then, weight value for each criterion and sub criteria was calculated using the rank order centroid technique. Analysis shows that academic qualification criterion has the highest weight (0.4207), followed by work experience (0.2039), teaching ability (0.2030), research activity (0.1108) and lastly personality (0.0618). In conclusion, decision makers can use these findings as additional information to be applied in the decision making process regarding selection of the academic staf

Quality Management Practices and Performance Measurement in the Manufacturing Industry: An Instrument Validation = Amalan Pengurusan Kualiti dan Pengukuran Prestasi dalam Industri Pembuatan: Suatu Pengesahan Alat

The aim of this article was to validate an instrument of quality management practices (QMPs) and performance measurement for the manufacturing industry in Malaysia. QMPs and performance were measured using the following six value indicators: Management commitment, training, process management, quality tools, continuous improvement and organisational performance. A total of 480 questionnaires were distributed and 210 questionnaires were valid for analysis. A confirmatory factor analysis (CFA) approach was employed using analysis of moment structures (AMOS) software. The results for the hypothesised CFA model showed the following fit statistics: Comparative fit index (CFI) = 0.924, Tucker Lewis index (TLI) = 0.913 and root mean square error of approximation (RMSEA) = 0.061. The values of CFI and TLI≥ 0.9 and at the same time the value of RMSEA ≤ 0.08 showed that CFA model fits the data very well. Hence, the results of the study can be used by managers in manufacturing companies to consider and adapt their QMPs and performance assessments toward increasing competitiveness