Average

Môn học "Dự báo trong kinh doanh và kinh tế" với mục tiêu giúp các bạn sinh viên hiểu được những khái niệm cơ bản chuỗi dừng (stationarity) và không dừng (nonstationarity), hiểu được khái niệm kiểm định nghiệm đơn vị (unit root test); Biết được các mô hình giản đơn dùng để dự báo như mô hình san mũ Holt, san mũ Holt-Winters, và mô hình ARIMA (Autoregressive Integrated Moving Average);...Mời các bạn cùng tham khảo!

14p hoangvanlong23 16-07-2024 1 0   Download

Part 1 of ebook "Essentials of time series for financial applications" provides readers with contents including: Chapter 1 - Linear regression model; Chapter 2 - Autoregressive moving average (ARMA) models and their practical applications; Chapter 3 - Vector autoregressive moving average (VARMA) models; Chapter 4 - Unit roots and cointegration; Chapter 5 - Single-factor conditionally heteroskedastic models, ARCH and GARCH;...

244p daonhiennhien 03-07-2024 3 1   Download

Part 1 of ebook "Statistics and analysis of scientific data (Second edition)" provides readers with contents including: Chapter 1 - Theory of probability; Chapter 2 - Random variables and their distributions; Chapter 3 - Three fundamental distributions - binomial, Gaussian, and poisson; Chapter 4 - Functions of random variables and error propagation; Chapter 5 - Maximum likelihood and other methods to estimate variables; Chapter 6 - Mean, median, and average values of variables; Chapter 7 - Hypothesis testing and statistics;...

158p daonhiennhien 03-07-2024 4 1   Download

Part 1 of ebook "Stochastic processes and calculus: An elementary introduction with applications" provides readers with contents including: Chapter 1 - Introduction; Chapter 2 - Basic concepts from probability theory; Chapter 3 - Autoregressive moving average processes (ARMA); Chapter 4 - Spectra of stationary processes; Chapter 5 - Long memory and fractional integration; Chapter 6 - Processes with autoregressive conditional heteroskedasticity (ARCH);...

163p daonhiennhien 03-07-2024 1 1   Download

Part 1 of ebook "The elements of statistical learning: Data mining, inference, and prediction (Second edition)" provides readers with contents including: Chapter 1 - Introduction; Chapter 2 - Overview of supervised learning; Chapter 3 - Linear methods for regression; Chapter 4 - Linear methods for classification; Chapter 5 - Basis expansions and regularization; Chapter 6 - Kernel smoothing methods; Chapter 7 - Model assessment and selection; Chapter 8 - Model inference and averaging; Chapter 9 - Additive models, trees, and related methods;...

355p daonhiennhien 03-07-2024 2 1   Download

Efficient planning of the oral health workforce in Primary Health Care (PHC) is paramount to ensure equitable community access to services. This requires a meticulous examination of the population’s needs, strategic distribution of oral health professionals, and effective human resource management. In this context, the average time spent on care to meet the needs of users/families/communities is the central variable in healthcare professional workforce planning methods.

9p vishanshan 27-06-2024 1 1   Download

Despite word-of-mouth (WOM) and electronic WOM (eWOM) influencing people’s willingness to donate blood, no research has explored this behavior among blood service employees who are also donors. This underexplored segment is highly important, as they are generally committed to both the organization and the cause and are likely more informed on the topic of blood donation than the average donor.

12p vishanshan 27-06-2024 1 1   Download

The present study investigates the synthesis and analysis of zinc oxide nanoparticles (ZnO NPs) intended for use in electronic devices. ZnO NPs with an average crystallite size of 33 nm and a hexagonal wurtzite structure were produced by the combustion process. Scanning Electron Microscopy (SEM) revealed a densely packed, spherical morphology.

12p visergeyne 18-06-2024 0 0   Download

The paper presents the characteristics of the ISO-4037 narrow spectrum X-ray reference fields in 02 different manners: simulation using the SpekPy and measurement using a calibrated ionization chamber. The physical (air Kerma rate) and radiation (X-ray fluence-spectrumaveraged energy, the first and the second half value layers, as well as the beam homogeneity coefficient) quantities were simulated using the SpekPy web-based simulation toolkit.

5p viambani 18-06-2024 3 1   Download

The parameters of the ISO-4037 wide spectrum (W-series) X-ray reference fields were simulated using the SpekPy web-based simulation software. One of the most important physical quantities (air Kerma rate) and other radiation quantities (X-ray fluence spectrum and its averaged energy, the first and the second half value layers, as well as the beam homogeneity coefficient) were also deduced.

4p viambani 18-06-2024 1 1   Download

Part 2 of ebook "Numerical modelling of wave energy converters: State-of-the-art techniques for single devices and arrays" provides readers with contents including: wave energy converter array modelling techniques; conventional multiple degree-of-freedom array models; semi-analytical array models; phase-resolving wave propagation array models; phase-averaging wave propagation array models; applications for wave energy converter models; control optimisation and parametric design;...

141p dongmelo 20-05-2024 4 2   Download

This study developed a statistical model for thermal analysis to describe the variation of railway temperature that aids in detecting the potential excessive displacement in the railway efficiently. In particular, the Seasonal autoregressive integrated moving average (SARIMA) model is adopted to learn and recognize the variation patterns of railroad temperature with time.

5p dathienlang1012 03-05-2024 4 0   Download

This study compares the accuracy of two popular time series forecasting models, namely the autoregressive integrated moving average (ARIMA) model and the long short-term memory (LSTM) model, in predicting daily gold prices from 2000 to 2023. The ARIMA model is a traditional approach that relies on past values to forecast future values, while the LSTM model is a deep learning technique that captures long-term dependencies in time series data.

16p dathienlang1012 03-05-2024 0 0   Download

The wave function regards like localized orbital locator, electron localized function, average localized ionization energy and non-covalent interaction are also examined as a means of theoretical evidence of the titled compound. The NBO calculations probe the intermolecular and intramolecular movement of charges, and additionally the molecule's stability. The ADMET properties are also considered for the compound with the assistance of Swiss ADMET online tool.

17p dianmotminh02 03-05-2024 1 1   Download

We study the dynamics of a double-well BEC system subjected to oscillating dissipation. The macroscopic model is described within the mean-field approximation while the noise effect due to large reservoir fluctuation has been averaged out to zero. We chose a simple dissipative memory kernel to produce a time-dependent oscillating dissipation. Our numerically calculated phase-space portraits and Lyapunov exponents show an enhanced route to chaos as one increases the driving dissipation amplitude.

14p dianmotminh02 03-05-2024 1 1   Download

In this study, we evaluated and compared the effectiveness of four different protocols (D, MJ, MA, and S) for separating MPs from water of different types (brackish, marine, and river). Known combinations of MP particles (polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS) and polyvinyl chloride (PVC) with size ranging between 150 μm and 700 μm were spiked into water samples. Our results showed that the average recovery effectiveness of microplastics using four studied methods ranged from 53% to 86%.

10p dianmotminh02 03-05-2024 2 1   Download

The experimental flux-weighted average cross section is compared with the theoretical prediction, for which the absolute cross section was calculated using the TALYS 1.95 code and the bremsstrahlung spectrum was simulated using the computer program MCNPX. The present experiment was carried out at the 100 MeV electron linac of the Pohang Accelerator Laboratory, POSTECH, Pohang, Korea.

12p dianmotminh02 03-05-2024 1 1   Download

This study aims at determining the mass concentrations of PM and health risks on pollution event days (episodes) in Ha Noi. Semi-daily samples (daytime and night-time) of PM2.5 and PM0.1 were collected at Hanoi University of Science and Technology, in December 2021. The daily PM2.5 concentrations were in the range of 39 - 204 µg/m3 (average of 119 µg/m3).

11p dianmotminh02 03-05-2024 7 3   Download

This study also compares the predictive capability of these models to the model using average annual rainfall data that was widely used in previous studies. Finally, the best model fit is used for landslide spatial prediction mapping.

19p dianmotminh02 03-05-2024 4 2   Download

This paper analyzes a monthly global gridded sea-surface wind dataset from Jan 1991 to Dec 2020, sourced from the International Comprehensive Ocean-Atmosphere Data Set (ICOADS). The goal is construct schematic maps depicting the monthly average distributions of sea-surface wind speeds and directions in the East Vietnam Sea.

10p dianmotminh02 03-05-2024 4 2   Download