Consulta: subjectFacets:"Time series analysis"
Registros recuperados: 16
Data/hora: 11/06/2024 16:30:35

Análise de homogeneidade de temperatura mínima mensal para o Estado de São Paulo.
Provedor de dados: 14
Autores: CARVALHO, J. R. P. de; NAKAI, A. M.; OLIVEIRA, A. F. de; ASSAD, E. D.
Neste trabalho, o pacote Climatol-R foi aplicado a 122 séries mensais de temperatura mínima, cobrindo o interior do estado de São Paulo para os anos 1940 até 2012.
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E)
Palavras-chave: Série temporal; Climatol-R; Variabilidade climatológica; Climatological variability; Estatística; Homogeneização; Statistics; Homogenization; Time series analysis.
Ano: 2016
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/1047606

Mise en evidence des profils d'évolution pluariannuelle associés aux series de mesures de parametres hydrobiologiques effectuées dans l'estuaire de la Seine dans le cadre du reseau national d'observation de la qualité du milieu marin
Provedor de dados: 5
Autores: Gallet, P.
The author deals with hydrobiological data obtained monthly by the French marine pollution network. The mathematical analysis gives a representation of ammonium, phosphates, silicate, nitrogen and dissolved oxygen evolution from 1976 to 1983.
Tipo: Text
Palavras-chave: Mathematical models; Estuaries; Long term changes; Pollution monitoring; Water quality; Time series analysis; Physicochemical properties; Water properties.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/acte-1296.pdf

Time series analysis of interrupted long-term data set (1961-1991) of zooplankton abundance in Gulf of Maine (northern Atlantic, USA)
Provedor de dados: 5
Autores: Licandro, P; Conversi, A; Ibanez, F; Jossi, J.
The main interannual and seasonal signals have been extracted from a multi-decadal data set of zooplankton collected with the Continuous Plankton Recorder in the Gulf of Maine, from January 1961 to December 1991. The monthly abundances of seven species or genera of copepods representing the dominant biomass in the area were considered. The presence of a large consecutive gap (35 months) prevented the use of statistical methods for the prediction of missing data. The eigen-vector filtering (EVF) method was then used on the original time series, while retaining the missing values. For each zooplankton taxon, two principal modes of variability (F-1 and F-2) were extracted, representing the interannual and seasonal variations, respectively. Results of EVF...
Tipo: Text
Palavras-chave: Calanus finmarchicus; Golfe du Maine; Données manquantes; Séries temporelles; Zooplancton; Calanus finmarchicus; Gulf of Maine; Missing data; Time series analysis; Zooplankton.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/00322/43342/42885.pdf

Microevents produced by gas migration and expulsion at the seabed: a study based on sea bottom recordings from the Sea of Marmara
Provedor de dados: 5
Autores: Tary, Jean-baptiste; Geli, Louis; Guennou, Claude; Henry, Pierre; Sultan, Nabil; Cagatay, N.; Vidal, V.
Different types of 4-component ocean bottom seismometers (OBS) were deployed for variable durations ranging from 1 week to about 4 months in 2007, over soft sediments covering the seafloor of the Tekirdag Basin (western part of the Sea of Marmara, Turkey). Non-seismic microevents were recorded by the geophones, but generally not by the hydrophones, except when the hydrophone is located less than a few tens of centimetres above the seafloor. The microevents are characterized by short durations of less than 0.8 s, by frequencies ranging between 4 and 30 Hz, and by highly variable amplitudes. In addition, no correlation between OBSs was observed, except for two OBSs, located 10 m apart. Interestingly, a swarm of similar to 400 very similar microevents (based...
Tipo: Text
Palavras-chave: Time series analysis; Gas and hydrate systems; Body waves; Interface waves; Seismic attenuation; Wave propagation.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00089/20012/17825.pdf

Time series analysis of tuna and swordfish catches and climate variability in the Indian Ocean (1968-2003)
Provedor de dados: 5
Autores: Corbineau, A; Rouyer, Tristan; Cazelles, B; Fromentin, Jean-marc; Fonteneau, A; Menard, Felix.
We analysed the patterns of variation that characterize 33 catch time series of large pelagic fishes exploited by the Japanese and Taiwanese longline fisheries in the Indian Ocean from 1968 to 2003. We selected four species, the yellowfin (Thunnus albacares), the bigeye (T. obesus), the albacore (T. alalunga), and the swordfish (Xiphias gladius) and aggregated data into five biogeographic provinces of Longhurst (2001). We carried out wavelet analyses, an efficient method to study non-stationary time series, in order to get the time-scale patterns of each signals. We then compared and grouped the different wavelet spectra using a multivariate analysis to identify the factors (species, province or fleet) that may influence their clustering. We also...
Tipo: Text
Palavras-chave: Indian Ocean; Dipole Mode Index; Longline fisheries; Wavelet analysis; Time series analysis; Pelagic fishes.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-4714.pdf

Complex interplays among population dynamics, environmental forcing, and exploitation in fisheries
Provedor de dados: 5
Autores: Rouyer, Tristan; Fromentin, Jean-marc; Menard, Felix; Calzelles, B; Briand, K; Pianet, R; Planque, Benjamin; Stenseth, N.
The patterns of variations in fisheries time series are known to result from a complex combination of species and fisheries dynamics all coupled with environmental forcing (including climate, trophic interactions, etc.). Disentangling the relative effects of these factors has been a major goal of fisheries science for both conceptual and management reasons. By examining the variability of 169 tuna and billfish time series of catch and catch per unit effort (CPUE) throughout the Atlantic as well as their linkage to the North Atlantic Oscillation (NAO), we find that the importance of these factors differed according to the spatial scale. At the scale of the entire Atlantic the patterns of variations are primarily spatially structured, whereas at a more...
Tipo: Text
Palavras-chave: Time series analysis; North Atlantic Oscillation; Atlantic tuna.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-3984.pdf

Time series of ocean measurements. Volume 2 - 1984
Provedor de dados: 20
Tipo: Book
Palavras-chave: Oceanography; Oceanographic data; Oceanography; Oceanographic surveys; Time series analysis; Sea level measurement; Sea level changes; Seasonal variations; Time series analysis; Oceanography; Http://aims.fao.org/aos/agrovoc/c_28778; Http://aims.fao.org/aos/agrovoc/c_12889.
Ano: 1985
URL: http://hdl.handle.net/1834/2737

Intercambio de calor superficial en la estación de La Libertad
Provedor de dados: 20
Autores: Garcés Vargas, J.
Se realiza un análisis de las series de tiempo mensuales de los parámetros meteorológicos-oceanográficos y los diferentes flujos de calor obtenidos mediante relaciones empíricas de la estación ubicada en La Libertad desde mediados de 1988 hasta finales de 1997, obteniéndose las climatologías mensuales así como estadísticas interesantes, aparentemente los datos no muestran una relación entre el intercambio de calor superficial y El Niño-Oscilación Sur.
Tipo: Journal Contribution
Palavras-chave: Climatology; Oceanographic data; Time series analysis; Climatology; Time series analysis; Http://aims.fao.org/aos/agrovoc/c_1671; Http://aims.fao.org/aos/agrovoc/c_28778.
Ano: 2000
URL: http://hdl.handle.net/1834/2236

Time series of ocean measurements. Vol. 3
Provedor de dados: 20
Tipo: Book
Palavras-chave: Oceanography; Oceanography; Oceanographic data; Physical properties; Physical oceanography; Plankton surveys; Hydrographic data; Hydrographic surveys; Time series; Time series analysis; Temperature data; Physical oceanography; Time series analysis; Oceanography; Physical properties; Http://aims.fao.org/aos/agrovoc/c_5830; Http://aims.fao.org/aos/agrovoc/c_28778; Http://aims.fao.org/aos/agrovoc/c_12889; Http://aims.fao.org/aos/agrovoc/c_13328.
Ano: 1986
URL: http://hdl.handle.net/1834/2803

Analysis and Forecast of Shaanxi GDP Based on the ARIMA Model
Provedor de dados: 31
Autores: Ning,   Wei; Kuan-jiang,   Bian; Zhi-fa,   Yuan.
Based on the 2008 Shaanxi Statistical Yearbook and the relevant data of Shaanxi GDP in the years 1952-2007, SPSS statistical software and time series analysis are used to establish ARIMA (1.2,1) time series model, according to the four steps, recognition rules and stationary test of time series under AIC criterion. ACF graph and PACF graph are used to conduct the applicability test on model. Then, the actual value and predicted value in the years 2002-2007 are compared in order to forecast the GDP of Shaanxi Province in the next 6 years based on this model. Result shows that the relative error of actual value and predicted value is within the range of 5%, and the forecasting effect of this model is relatively good. It is forecasted that the GDP of Shaanxi...
Tipo: Journal Article
Palavras-chave: GDP; ARIMA model; ACF graph; PACF graph; Time series analysis; Agribusiness.
Ano: 2010
URL: http://purl.umn.edu/93238

Time Series Analysis
Provedor de dados: 31
Autores: Diebold,   F.X.; Kilian,   L.; Nerlove,   Marc.
We provide a concise overview of time series analysis in the time and frequency domains, with lots of references for further reading.
Tipo: Working or Discussion Paper
Palavras-chave: Time series analysis; Time domain; Frequency domain; Research Methods/ Statistical Methods.
Ano: 2006
URL: http://purl.umn.edu/28556

Improved Program Planning Generates Large Benefits in High Risk Crop Farming – A Profitable Application of Time Series Models and Stochastic Optimization
Provedor de dados: 31
Autores: Musshoff,   Oliver; Hirschauer,   Norbert.
Agricultural production relies to a great extent on biological processes in natural environments. In addition to volatile prices, it is thus heavily exposed to risks caused by the variability of natural conditions such as rainfall, temperature and pests. With a view to the apparently lacking support of risky farm production program decisions through formal planning models, the objective of this paper is to examine whether, and eventually by how much, farmers’ “intuitive” program decisions can be improved through formal statistical analyses and stochastic optimization models. In this performance comparison, we use the results of the formal planning approach that are generated in a quasi ex-ante analysis as a normative benchmark for the empirically observed...
Tipo: Conference Paper or Presentation
Palavras-chave: Stochastic optimization; Program planning; Time series analysis; Crop Production/Industries.
Ano: 2008
URL: http://purl.umn.edu/44174

Sophisticated Program Planning Approaches Generate Large Benefits in High Risk Crop Farming
Provedor de dados: 31
Autores: Musshoff,   Oliver; Hirschauer,   Norbert.
Agricultural production relies to a great extent on biological processes in natural environments. In addition to volatile prices, it is thus heavily exposed to risks caused by the variability of natural conditions such as rainfall, temperature and pests. With a view to the apparently lacking support of risky farm production program decisions through formal planning models, the objective of this paper is to examine whether, and eventually by how much, farmers’ “intuitive” program decisions can be improved through formal statistical analyses and stochastic optimization models. In this performance comparison, we use the results of the formal planning approach that are generated in a quasi ex-ante analysis as a normative benchmark for the empirically observed...
Tipo: Conference Paper or Presentation
Palavras-chave: Stochastic optimization; Stochastic processes; Production risk; Program planning; Time series analysis; C1; C61; M11; Q12.
Ano: 2008
URL: http://purl.umn.edu/36865

Measuring the Price Volatility of Certain Field Crops in South Africa using the ARCH/GARCH Approach
Provedor de dados: 31
Autores: Jordaan,   Henry; Grove,   Bennie; Jooste,   Andre; Alemu,   A.G.
The conditional volatility in the daily spot prices of the crops traded on the South African Futures Exchange (yellow maize, white maize, wheat, sunflower seed and soybeans) is determined.  The volatility in the prices of white maize, yellow maize and sunflower seed have been found to vary over time, suggesting the use of the GARCH approach in these cases.  Using the GARCH approach, the conditional standard deviation is the measure of volatility, and distinguishes between the predictable and unpredictable elements in the price process.  This leaves only the stochastic component and is hence a more accurate measure of the actual risk associated with the price of the crop.  The volatility in the prices of wheat and soybeans was found to be constant over...
Tipo: Journal Article
Palavras-chave: Price volatility; Field crops; SAFEX; Time series analysis; ARCH/GARCH; Demand and Price Analysis.
Ano: 2007
URL: http://purl.umn.edu/8013

Volatility in US and Italian agricultural markets, interactions and policy evaluation
Provedor de dados: 31
Autores: Rosa,   Franco; Vasciaveo,   Michela.
The aim of this paper is to analyse the volatility and interactions among prices of agricultural commodities in Italy and US using the time series analysis. The cross market interactions are examined to test the hypothesis that the increased volatility of agricultural prices has been caused by crude oil price, then the cointegration and causality among different markets is also tested. For this analysis the spot prices of wheat, corn, soybeans in US and Italy and crude oil prices spanning from 2002 to 2010 are used. The results suggest the following considerations: i) the existence of causality in US markets with exogeneity of the oil on the US agricultural commodities, ii) evidence of cointegration between US and Italian commodities, suggesting a...
Tipo: Presentation
Palavras-chave: Time series analysis; Agricultural commodity prices; Linear and nonlinear Granger causality; Market integration; Risk and Uncertainty; C14; C19; Q13.
Ano: 2012
URL: http://purl.umn.edu/122530

Approximate Entropy as a measure of complexity in sap flow temporal dynamics of two tropical tree species under water deficit
Provedor de dados: 42
Autores: Souza,Gustavo M.; Ribeiro,Rafael V.; Santos,Mauro G.; Ribeiro,Henrique L.; Oliveira,Ricardo F.
Approximate Entropy (ApEn), a model-independent statistics to quantify serial irregularities, was used to evaluate changes in sap flow temporal dynamics of two tropical species of trees subjected to water deficit. Water deficit induced a decrease in sap flow of G. ulmifolia, whereas C. legalis held stable their sap flow levels. Slight increases in time series complexity were observed in both species under drought condition. This study showed that ApEn could be used as a helpful tool to assess slight changes in temporal dynamics of physiological data, and to uncover some patterns of plant physiological responses to environmental stimuli.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Approximate Entropy; Complexity; Sap flow; Time series analysis; Tropical ecophysiology; Water deficit.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000300015