Time Series Analysis, Cointegration, and Applications

The two prize winners in Economics this year would describe themselves as "Econometricians," so I thought that I should start by explaining that term. One can begin with the ancient subject of Mathematics which is largely concerned with the discovery of relationships between deterministic variables using a rigorous argument. (A deterministic variable is one whose value is known with certainty.) However, by the middle of the last millennium it became clear that some objects were not deterministic, they had to be described with the use of probabilities, so that Mathematics grew a substantial sub-field known as "Statistics." This later became involved with the analysis of data and a number of methods have been developed for data having what may be called "standard properties."time series; cointegration

Developing system models to help Great Britain's railways embrace innovative technologies with confidence

Railways are under pressure to become more efficient and cut their costs; innovation has a part to play in achieving these goals. The railway is, however, a complex and closely coupled system, making it difficult in the early stages of development, to be clear what the system-wide impact of innovation will be. The research covered in this paper stems from the idea that computer-based models of existing systems can help overcome this problem, by providing a baseline framework against which the impact of innovation can be identified. The paper describes development of a repeatable modelling methodology, which elicits\ud objective system data from Railway Group Standards and integrates it using CORE®, a powerful system modelling tool, to create system models. The ability of such models to help identify impacts is verified, using as an example the introduction of RailBAM (a new technology that acoustically monitors the health of rolling stock axle bearings) into the existing hot axle bearing detection system

Rapid Detection of Leishmania infantum Infection in Dogs: Comparative Study Using an Immunochromatographic Dipstick Test, Enzyme-Linked Immunosorbent Assay, and PCR

Current zoonotic visceral leishmaniasis (ZVL) control programs in Brazil include the culling of Leishmania infantum-infected reservoir dogs, a strategy that has failed to prevent a rise of canine and human ZVL cases over the past decade. One of the main reasons this strategy has failed is because of a long delay between sample collection, sample analysis, and control implementation. A rapid, sensitive, and specific diagnostic tool would be highly desirable, because it would allow control interventions to be implemented in situ. We compared an immunochromatographic dipstick test to enzyme-linked immunosorbent assay (ELISA) and PCR for detecting L. infantum infections in dogs from an area of ZVL endemicity in Brazil. The dipstick test was shown to have 61 to 75% specificity and 72 to 77% sensitivity, compared to 100% specificity for both ELISA and PCR and 71 to 88% and 51 to 64% sensitivity for ELISA and PCR, respectively. Of the field samples tested, 92 of 175 (53%), 65 of 175 (37%), and 47 of 175 (27%) were positive by dipstick, ELISA, and PCR, respectively. The positive and negative predictive values for the tested dipstick were 58 to 77% and 75%, respectively. Efforts should be made to develop a more specific dipstick test for diagnosis of leishmaniasis, because they may ultimately prove more cost-effective than currently used diagnostic tests when used in mass-screening surveys

Modeling Amazon Deforestation for Policy Purposes

Brazil has long ago removed most of the perverse government incentives that stimulated massive deforestation in the Amazon in the 70s and 80s, but one highly controversial policy remains: Road building. While data is now abundantly available due to the constant satellite surveillance of the Amazon, the analytical methods typically used to analyze the impact of roads on natural vegetation cover are methodologically weak and not very helpful to guide public policy. This paper discusses the respective weaknesses of typical GIS analysis and typical municipality level regression analysis, and shows what would be needed to construct an ideal model of deforestation processes. It also presents an alternative approach that is much less demanding in terms of modeling and estimation and more useful for policy makers as well.Deforestation, Amazon, Brazil, econometric modeling

Confirming the existence of π-allyl-palladium intermediates during the reaction of meta photocycloadducts with palladium(ii) compounds

The transient existence of π-allyl-palladium intermediates formed by the reaction of Pd(OAc)2 and anisole-derived meta photocycloadducts has been demonstrated using NMR techniques. The intermediates tended to be short-lived and underwent rapid reductive elimination of palladium metal to form allylic acetates, however this degradation process could be delayed by changing the reaction solvent from acetonitrile to chloroform

Plant species first recognised as naturalised for New South Wales in 2002 and 2003, with additional comments on species recognised as naturalised in 2000–2001

Information is provided on the taxonomy and distribution of 71 taxa of naturalised or naturalising plants newly recorded for the state of New South Wales during the period 1 January 2002 to 31 December 2003. Of these taxa, 32 are new records for Australia (prefaced with a †). These species are: Abutilon pictum, Acanthus mollis, †Aesculus indica (naturalising), Agapanthus praecox subsp. orientalis, Ajuga reptans, †Anigozanthos flavidus, Aquilegia vulgaris, Arbutus unedo, †Athertonia diversifolia (naturalising), †Bergenia x schmidtii (naturalising), Bromus catharticus subsp. stamineus, Bryophyllum daigremontianum, Bryophyllum fedtschenkoi, Calyptocarpus vialis, †Ceiba speciosa (naturalising), Cereus uruguayanus, †Cestrum x cultum, †Chamaecyparis lawsoniana, Cistus salviifolius, †Clematis montana, †Coprosma x cunninghamii, Coprosma robusta, Cornus capitata, Cotoneaster simonsii, Cotoneaster x watereri group, Crinum moorei, Cupressus lusitanica, †Cylindropuntia fulgida var. mamillata forma monstrosa, †Cylindropuntia prolifera, Cylindropuntia tunicata, Desmanthus virgatus, Drosanthemum candens, †Elaeagnus umbellata (naturalising), †Eragrostis trichophora, †Eupatorium lindleyanum, †Gibasis pellucida, Glechoma hederacea, †Hesperis matronalis, Hieracium aurantiacum subsp. carpathicola, †Inga edulis (naturalising), †Juniperus conferta (naturalising), †Justicia caudata, Lamium galeobdolon, Lathyrus tingitanus, †Lysimachia fortunei, †Maackia amurensis, †Monstera deliciosa, †Murdannia keisak, Odontonema tubaeforme, Oxalis vallicola, Phoenix canariensis, †Physostegia virginiana, Pinus patula, Pittosporum eugenioides, †Pittosporum ralphii, Pittosporum tenuifolium, Plectranthus ecklonii, †Potentilla vesca, †Prunus campanulata, †Rhododendron ponticum, Rosa luciae, Rubus rugosus, Ruellia squarrosa, †Senna multijuga, Stapelia gigantea, Stephanophysum longifolium, Strobilanthes anisophylla, †Tabebuia chrysotricha, †Tabebuia impetiginosa, †Tradescantia pallida and Ulmus x hollandica. Additional notes and name changes are recorded for plants first recognised as naturalised for New South Wales over the period 2000–2001. The identification of several naturalised taxa occurring in New South Wales has been corrected. Plants formerly identified as Pinus nigra var. corsicana are now considered to be Pinus halepensis; Cylindropuntia arbuscula is Cylindropuntia kleiniae, Cylindropuntia tunicata is Cylindropuntia rosea, Abrus precatorius subp. precatorius is now Abrus precatorius subsp. africanus and Cotoneaster ?horizontalis is Cotoneaster microphyllus. Further field studies have revealed that Cylindropuntia leptocaulis, Cylindropuntia spinosior, Hypericum kouytchense and Chamaesyce ophthalmica are more widespread than previously thought

Environmental determinants of child mortality in Kenya

This paper focuses on the determinants of infant and child mortality in Kenya. It specifically examines how infant and child mortality is related to the household’s environmental and socio-economic characteristics, such as mother’s education, source of drinking water, sanitation facility, type of cooking fuels and access to electricity. A hazard rate framework is used to analyze the determinants of child mortality. Duration models are easily applicable to the problem of child mortality as this class of models straightforwardly accounts for problems like right-censoring, structural modeling and time varying covariates which traditional econometric techniques cannot handle adequately. A household’s environmental and socio-economic characteristics are found to have significant impact on child mortality. Policies aimed at achieving the goal of reduced child mortality should be directed on improving the household’s environmental and or socio-economic status if this goal is to be realized