Automatic Time Series Forecasting: The forecast Package for R

Automatic forecasts of large numbers of univariate time series are often needed in business and other contexts. We describe two automatic forecasting algorithms that have been implemented in the forecast package for R. The first is based on innovations state space models that underly exponential smoothing methods. The second is a step-wise algorithm for forecasting with ARIMA models. The algorithms are applicable to both seasonal and non-seasonal data, and are compared and illustrated using four real time series. We also briefly describe some of the other functionality available in the forecast package.

Automatic time series forecasting: the forecast package for R.

Automatic forecasts of large numbers of univariate time series are often needed in business and other contexts. We describe two automatic forecasting algorithms that have been implemented in the forecast package for R. The first is based on innovations state space models that underly exponential smoothing methods. The second is a step-wise algorithm for forecasting with ARIMA models. The algorithms are applicable to both seasonal and non-seasonal data, and are compared and illustrated using four real time series. We also briefly describe some of the other functionality available in the forecast package.ARIMA models; automatic forecasting; exponential smoothing; prediction intervals; state space models; time series, R.

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Effect of girls' secondary school stipend on completed schooling, age at marriage, and age at first birth: Evidence from Bangladesh

There are many studies on the effects of conditional cash transfer programmes on enrolment, productivity and poverty reduction but very few on causal effects on ages at marriage and first birth. And none of them considers the convergence effect. This paper provides new evidence on effects of the Female Secondary Stipend Programme in Bangladesh as an exogenous variation in time and region on schooling, ages at marriage and first birth outcomes with regression discontinuity and difference-in-difference approaches. The regression discontinuity results show that the programme increased completed years of schooling by at least 0.4 years, and delayed age at first marriage and age at first birth by at least 0.4 and 0.3 years respectively. We also show that the difference-in-difference method predicts biased results

Effects of locally produced bacterial phytase on humoral immunity, live body weight and blood characteristics in broilers vaccinated against Newcastle disease

Immune responses in association with body weight performance and hemato-biochemical constituents might influence the Newcastle disease (ND) vaccination by dietary phytase supplementation (Enterobacter sakazakii ASUA273). The objective of the study was to determine the effects of bacterial phytase supplementation on humoral immunity in association with live body weight and blood characteristics of broilers. Male-day-old Cobb broilers (n=180) were assigned into four phytase treatments (0, 500, 1000 and 1500 FTU/kg-1 of diet) with 12 cages comprised of 3 replicates and each cage contained 15 birds. Birds were maintained on formulated basal diet based with available phosphorus (0.19%) that lasted up to six weeks in feed. Birds were vaccinated with a live ND vaccine at day-old and 21 day-old. Two birds were randomly selected from each treatment weekly. Specific antibody to ND, non-specific immunoglobins (IgM, IgG, and IgA) and live body weight were measured weekly. At the end of experiment, the complete haemato-biochemical constituents were determined. Data of humoral immunity with live body weight and haemato- biochemical values were analysed based on factorial arrangement (treatments×weeks) of completely randomized design (CRD), respectively. Response of the humoral immunity shown that although serum-antibody of ND, IgM, and IgG levels were not improved, the mucosal IgA contents were increased with the increasing phytase doses. The live body weights of broilers were significantly increased (P<0.05) to the graded levels of phytase supplementation throughout the experimental period. Cumulative effects of mucosal IgA contents and live body weights of broilers showed significant (P<0.05) interaction between the effects of phytase levels and effects of weeks. Overall, phytase dose at 1500 FTU/kg-1 of diet over the age of 6 weeks-old showed the best performance. Conversely, no significant, sequential, and consistent treatment effects were observed on hemato-biochemical constituents in broiler chickens. It is therefore, concluded that the efficacy of this local phytase was flourished in respective to mucosal IgA contents and live body weights of broilers

Cultural Identities in Sustaining Religious Communities in the Arctic Region: An Ethnographic Analysis on Religiosity from the Northern Viewpoint

Northern countries are facing the challenges of declining human capital, and admitting immigrants, many of whom belong to religious minorities, to satisfy the demand for labour. If northern societies accept multiculturalism and immigrants, they should not disregard the cultures and religious practices (for example, ritual slaughter) of immigrants, as they need to survive and integrate as a minority community in a secular society. However, there is clash between secularism and religions permitting animal slaughter, which is prohibited by some and allowed by other European countries. Community viability and sustainability depend partly on the exercise of community beliefs and ideology that support identity behaviour. This study will present an ethnographic analysis of the religiosity related to ritual slaughter and Muslim cultural identity in the European Arctic region and explore how religious relativism and practice sustain the community and support the overall integration of the Muslim minority in the North

Development of a long-term climatology of tropical 1 cyclones and depressions for the South Pacific 2 Ocean basin

Tropical cyclones (TCs) are one of the most destructive synoptic systems that can cause enormous loss of life and property damages in the South Pacific Island nations. The impact of tropical depressions (TDs, i.e., weaker systems that do not develop into TCs) can also be staggering in the region in terms of heavy flooding and landslides, but a lack of complete records (reliable data prior to 1950) often hinders research involving TD impacts. A methodology has been developed here to detect TDs in the ERA-5 (the fifth generation European Centre for Medium-Range Weather Forecasts-ECMWF atmospheric reanalysis of the global climate) and 20CR (the Twentieth Century Reanalysis) dataset using the Okubo–Weiss–Zeta parameter (OWZP) detection scheme. The new South Pacific Enhanced Archive for Tropical Cyclones dataset (SPEArTC), the Dvorak analysis of satellite-based cloud patterns over the South Pacific Ocean basin, rainfall dataset for various stations in the South Pacific and historical archives have been utilised to validate ERA5/20CR-derived TCs and TDs. Results indicate that the OWZP method shows substantial skill in capturing the realistic climatological distribution of TCs and TDs for the South Pacific Ocean in both reanalyses dataset. The 20CR-derived TCs and TDs resemble several key characteristics of the observational records, including spatial distribution of genesis locations and track shapes. This gives us confidence that the 20CR-derived long-term records of TCs and TDs can serve as an effective tool for examining historical changes in various characteristics of TCs and TDs, particularly in the context of anthropogenic climate change. Utilizing the reconstructed proxies of TCs and TDs, their climatic connections with the El Niño Southern Oscillation (ENSO), the Interdecadal Pacific Oscillation (IPO), and the combined ENSO-IPO phases have been examined. Results show clear spatial shifts in TC activity between La Niña and El Niño phases with activity in the region 1400-1700E (1700-2200E) occurring during La Niña (El Niño) events. However, when IPO is considered synergistically with ENSO phases, we found that the combination of El Niño and the positive phase of IPO (+IPO) substantially enhances TC numbers (may be artifact influence) in both domains, noting the modulation between the two phases themselves. Similarly, La Niña and the negative phase of the IPO (-IPO) is found to enhance TC numbers in 1400-1700E. It is shown for the first time that the combined phases of El Niño and +IPO account for increased TC activity, as opposed to the combined phase of La Niña and -IPO, in the eastern sub-region. Similarly, the combined phase of La Niña and +IPO, as opposed to the combined phase of El Niño and -IPO, account for increased TC activity in the western sub-region. However, unlike TCs, the patterns of ENSO variability seem to be reversed for TDs. Changes in large-scale environmental conditions, such as environmental vertical wind shear, low-level cyclonic relative vorticity, mid-tropospheric relative humidity and sea surface temperature are linked to the various modes of variability patterns and their synergistic relationships. Results can have substantial implications, particularly on the predictability of TCs and TDs associated with the two important modes of natural variability in the South Pacific.Doctor of Philosoph

Study of Extensions to the Linear Sampling Method for Electromagnetic Inverse Scattering

The linear sampling method (LSM) is a simple and effective qualitative method to reconstruct the support of unknown object by solving inverse scattering problem. The solution is done based on the field radiated by the elementary source located in a set of test points. In this thesis, the LSM formulation, limitations of standard LSM and extensions of LSM are discussed. Standard LSM can reconstruct simply connected objects, but it fails in case of concave or not simply connected objects. However, it can reconstruct the convex hull for such objects. Some extensions to LSM have been proposed to avoid these limitations. Two of these extensions are generalized LSM (GLSM) and multipole based LSM (MLSM). GLSM is formulated by generalizing the right side of the linear equation to higher order multipoles. This provides more information about the radiated field. The reconstruction is even better by using some post-processing scheme such as a modified indicator function and higher values for the regularization parameter. But GLSM cannot reconstruct the actual shape for some complex objects. MLSM is based on physical regularization. This method analyzes the multipole expansion of the scattered field. Only monopole and dipole terms are used for the reconstruction. This modification shows better reconstruction than the mathematical regularization in GLSM. Another advantage of MLSM is that the threshold for boundary contour is constant for all types of objects. From the results, it is evident that MLSM is somewhat better than GLSM when the object’s complex hull is very different than the object itself. However, higher permittivity affects the solutions. It can be avoided by using higher value of regularization parameter in GLSM but in MLSM there is no known remedy