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A note on the performance measure of conservation auctions AgEcon
Latacz-Lohmann, Uwe; Schilizzi, Steven.
We argue that previous assessments of discriminatory-price conservation auctions may have systematically overestimated their performance relative to uniform-payment schemes due to an inappropriate counterfactual comparison. We demonstrate that the cost curve (and not the bid curve) is the relevant supply curve when a uniform payment is offered and provide a theoretically rigorous counterfactual based on that insight. We estimate that the performance of BushTender may have been overrated by more than 50%.
Tipo: Working or Discussion Paper Palavras-chave: Auctions; Procurement; Tenders; Conservation; Economic experiments; Model validation; Plus: assessment method; Agricultural policy; Environmental policy; Market-based instruments; Environmental Economics and Policy; Research Methods/ Statistical Methods; C91; C92; D44; Q24; Q28.
Ano: 2011 URL: http://purl.umn.edu/100885
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Allometric models for estimating Moringa oleifera leaflets area Ciência e Agrotecnologia
Macário,Ana Paula Silva; Ferraz,Rener Luciano de Souza; Costa,Patrícia da Silva; Brito Neto,José Félix de; Melo,Alberto Soares de; Dantas Neto,José.
ABSTRACT Moringa oleifera is a species of great economic, social and environmental importance, being employed for multiple purposes. Thus, the objective of this study was to fit regression models for estimating leaflets area as non-destructive method from linear measurements of leaflets of M. oleifera seedlings. The study was carried out at the Center for Agrarian and Environmental Sciences of the Paraíba State University. Three hundred leaflets of M. oleifera were collected and measured to determine length “L” and width “W” and, subsequently, leaflets area was quantified through ImageJ® software. Using 200 leaflets, the univariate regression models were fitted, adopting length, width or the product of these dimensions “LW” and a bivariate model based on...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Linear measurements; Empirical modeling; Model validation.
Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542020000100212
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An end-to-end coupled model ROMS-N(2)P(2)Z(2)D(2)-OSMOSE of the southern Benguela foodweb: parameterisation, calibration and pattern-oriented validation ArchiMer
Travers-trolet, Morgane; Shin, Yunne-jai; Field, J. G..
In order to better understand ecosystem functioning under simultaneous pressures (e.g. both climate change and fishing pressures), integrated modelling approaches are advocated. We developed an end-to-end model of the southern Benguela ecosystem by coupling the high trophic level model OSMOSE with a biophysical model (ROMS-N(2)P(2)Z(2)D(2)). OSMOSE is a spatial, multispecies, individual-based model simulating the whole life cycle of fish with fish schools interacting through opportunistic and size-based predation. It is linked to the biogeochemical model through the predation process; plankton groups are food for fish and fish apply a predation mortality on plankton. Here we describe the two-way coupling between the models and follow a pattern-oriented...
Tipo: Text Palavras-chave: Individual-based model; Model validation; Pattern-oriented modelling; Trophic interactions; Two-way coupling.
Ano: 2014 URL: https://archimer.ifremer.fr/doc/00193/30457/83335.pdf
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Characterizing Species at Risk I: Modeling Rare Species Under the Northwest Forest Plan Ecology and Society
Marcot, Bruce G; USDA Forest Service; bmarcot@fs.fed.us.
The Northwest Forest Plan in the Pacific Northwest, United States includes directives for survey and site protection of hundreds of rare species across many taxonomic classes. To help direct survey activities, prioritize sites, and stand conditions for conservation of these species, I developed Bayesian belief network (BBN) models of habitat relationships and multiple stressors predicting presence of 12 rare species, and I present an example of predicting presence and absence of a rare fungus. The BBN models are developed along a rigorous process of expert judgment, peer review, reconciliation, accuracy testing, and incremental updating with known site data and validation data. Management implications of prediction errors are discussed.
Tipo: Peer-Reviewed Reports Palavras-chave: Bayesian belief networks; Bridgeoporus nobilissimus; Model validation; Northwest Forest Plan; Rare species models; Pacific Northwest..
Ano: 2006
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Desempenho e estabilidade de um biossensor eletroquímico utilizando eletrodos descartáveis para detecção de Salmonella sp. em leite. Repositório Alice
BRITO, F. A. E. de.
bitstream/item/219769/1/TS2020-011-dis-FAEB.pdf
Tipo: Tese/dissertação (ALICE) Palavras-chave: Imunossensor; Método de detecção; Validação; Detection method; Estocagem; Immunosensors; Model validation; Storage.
Ano: 2020 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1128838
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Development and validation of a reversed phase HPLC method for determination of anacardic acids in cashew (Anacardium occidentale) nut shell liquid. Repositório Alice
FILHO, F. O.; ALCÂNTARA, D. B.; RODRIGUES, T. H. S.; SILVA, L. M. A. e; SILVA, E. de O.; ZOCOLO, G. J.; BRITO, E. S. de.
bitstream/item/178250/1/ART18024.pdf
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Anacardium Occidentale; Castanha de Caju; Model validation; Cashew nuts.
Ano: 2018 URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1092152
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Evaluating conservation auctions with limited information: the policy maker’s predicament AgEcon
Schilizzi, Steven; Latacz-Lohmann, Uwe.
Buying environmental services from private landholders using tendering mechanisms are usually subject to a budget constraint. Auction theory has mostly focused on target-constrained auctions and is less well developed for this type of auction. This paper examines a theoretical model specifically developed for budget-constrained tenders and assesses its capacity to predict tendering performance under information limitations typical of those found in field applications. But this assessment cannot be done without complementing the model with controlled laboratory experiments. Subject to their external validity, we find that the model is able to make the correct policy recommendation when comparing the tender to an equivalent fixed price scheme, even when the...
Tipo: Working or Discussion Paper Palavras-chave: Auctions; Procurement; Tenders; Conservation; Economic experiments; Model validation; Environmental Economics and Policy; Land Economics/Use; C91; C92; D44; Q24; Q28.
Ano: 2011 URL: http://purl.umn.edu/100884
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EXAMINING ECONOMIC IMPACT AND RECOVERY IN SOUTH DAKOTA FROM THE 2002 DROUGHT AgEcon
Diersen, Matthew A.; Taylor, Gary.
During the 2002 drought, farm sector economic factors were monitored to assess the likely statewide economic impacts. Timely moisture during the spring of 2003 resulted in a sizeable wheat harvest relative to recent years. Prices in the fall of 2003 resulted in a sizeable wheat harvest relative to recent years. Prices in the fall of 2003 have also been significantly higher for cattle and soybeans compared to prices in recent years. As a result, there have been inquiries as to the extent of economic recovery in the farm sector of South Dakota. The purpose of this paper is to outline the estimation procedure used to assess the drought in 2002, validate the extent of the impact, and discuss potential mitigating effects observed during 2003. The results...
Tipo: Working or Discussion Paper Palavras-chave: Drought impacts; Farm sector; Multiplier effects; Model validation; Resource /Energy Economics and Policy.
Ano: 2003 URL: http://purl.umn.edu/32028
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Impacts of climate change on coastal benthic ecosystems: assessing the current risk of mortality outbreaks associated with thermal stress in NW Mediterranean coastal areas ArchiMer
Pairaud, Ivane; Bensoussan, Nathaniel; Garreau, Pierre; Faure, Vincent; Garrabou, Joaquim.
In the framework of climate change, the increase in ocean heat wave frequency is expected to impact marine life. Large-scale positive temperature anomalies already occurred in the northwestern Mediterranean Sea in 1999, 2003 and 2006. These anomalies were associated with mass mortality events of macrobenthic species in coastal areas (0–40 m in depth). The anomalies were particularly severe in 1999 and 2003 when thousands of kilometres of coasts and about 30 species were affected. The aim of this study was to develop a methodology to assess the current risk of mass mortality associated with temperature increase along NW Mediterranean continental coasts. A 3D regional ocean model was used to obtain the temperature conditions for the period 2001–2010, for...
Tipo: Text Palavras-chave: Climate change; Benthic communities; Ocean modelling; Model validation; Impact mapping.
Ano: 2014 URL: http://archimer.ifremer.fr/doc/00171/28210/27707.pdf
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Leaf area estimation from linear measurements in different ages of Crotalaria juncea plants Anais da ABC (AABC)
CARVALHO,JULIANA O. DE; TOEBE,MARCOS; TARTAGLIA,FRANCIELI L.; BANDEIRA,CIRINEU T.; TAMBARA,ANDRÉ L..
ABSTRACT The goal of this study was to estimate the leaf area of Crotalaria juncea according to the linear dimensions of leaves from different ages. Two experiments were conducted with C. juncea cultivar IAC-KR1, in the 2014/2015 sowing seasons. At 59, 82, 102, 129 days after sowing (DAS) of the first and 61, 80, 92, 104 DAS of the second experiment, 500 leaves were collected, totaling 4,000 leaves. In each leaf, the linear dimensions were measured (length, width, length/width ratio and length × width product) and the specific leaf area was determined through Digimizer and Sigma Scan Pro software, after scanning images. Then, 3,200 leaves were randomly separated to generate mathematical models of leaf area (Y) in function of linear dimension (x), and 800...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Non-destructive method; Image processing; Mathematical models; Model validation.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000401851
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Modeling growth and yield of loblolly pinestands under intensive management PAB
Ferraz Filho,Antonio Carlos; Scolforo,José Roberto Soares; Oliveira,Antonio Donizette de; Mello,José Márcio de.
Abstract:The objective of this work was to develop and validate a prognosis system for volume yield and basal area of intensively managed loblolly pine (Pinus taeda) stands, using stand and diameter class models compatible in basal area estimates. The data used in the study were obtained from plantations located in northern Uruguay. For model validation without data loss, a three-phase validation scheme was applied: first, the equations were fitted without the validation database; then, model validation was carried out; and, finally, the database was regrouped to recalibrate the parameter values. After the validation and final parameterization of the models, a simulation of the first commercial thinning was carried out. The developed prognosis system was...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pinus taeda; Model validation; Prognosis system; Pruning; Sawtimber; Thinning.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2015000800707
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Modeling of crop stem deflection in the context of combine harvester reel design and operation CIGR Journal
Moses Frank Oduori; University of Nairobi; Thomas Ochuku Mbuya; University of Nairobi; Jun Sakai; Kyushu University; Eiji Inoue; Kyushu University.
A model of crop stem deflection by the combine harvester reel is formulated.  The equations derived thereof are evaluated on the basis of empirical data that were acquired through deflection of crop stems in a ready-for-harvest Japonica rice in the field.  The empirical data are found to be in agreement with the theoretically derived equations. Applications of crop stem deflection to reel design and operation are discussed.  The derived crop stem deflection model should be applicable in other situations in which it becomes necessary to study the deflection of crop stems, particularly in the domain of agricultural machinery engineering. Keywords: combine harvester header, tined reel, crop stem deflection, rice crop, mathematical modeling, model validation,...
Palavras-chave: Combine harvester header; Tined reel; Crop stem deflection; Rice crop; Mathematical modeling; Model validation; Model application.
Ano: 2012 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/1575
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Performance assessment of a vertical axis turbine in a marine current flume tank and CFD modelling ArchiMer
Rolland, S.a.; Thatcher, M.; Ellis, R.; Gaurier, Benoit; Croft, T.n.; Cross, M..
As advances in numerical modelling techniques support the increased confidence in predictions from computer simulations, the need remains to have experimental verification built into the design process. This paper outlines the experimental investigation carried out on a shielded vertical axis turbine in a marine environment. The experiments consist of performance measurements and the use of particle image velocimetry on a small scale device in a marine current flume. The results demonstrate that the performance of the device can be modelled numerically; in particular, the results show that the numerical model used can correctly predict the increase in performance with Reynolds number.
Tipo: Text Palavras-chave: Computational fluid dynamics; Cross-flow turbine; Flume test; Power coefficient; Model validation.
Ano: 2015 URL: http://archimer.ifremer.fr/doc/00270/38162/36297.pdf
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Survey of stochastic models for wind and sea state time series ArchiMer
Monbet, Valérie; Ailliot, P; Prevosto, Marc.
The knowledge of sea state and wind conditions is of central importance for many offshore and nearshore operations. In this paper, we make a complete survey of stochastic models for sea state and wind time series. We begin with methods based on Gaussian processes, then non-parametric resampling methods for time series are introduced followed by various parametric models. We also propose an original statistical method, based on Monte Carlo goodness-of-fit tests, for model validation and comparison and this method is illustrated on an example of multivariate sea state time series. (C) 2006 Elsevier Ltd. All rights reserved.
Tipo: Text Palavras-chave: Model validation; Simulation; Nonlinear time series; Wind; Sea state.
Ano: 2007 URL: http://archimer.ifremer.fr/doc/2007/publication-2679.pdf
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Utilization of the cropgro-soybean model to estimate yield loss caused by Asian rust in cultivars with different cycle. Repositório Alice
RODRIGUES, R. de Á.; PEDRINI, J. E.; FRAISSE, C. W.; FERNANDES, J. M. C.; JUSTINO, F. B.; HEINEMANN, A. B.; COSTA, L. C.; VALE, F. X. R. do..
In recent years, crop models have increasingly been used to simulate agricultural features. The DSSAT (Decision Support System for Agrotechnology Transfer) is an important tool in modeling growth; however, one of its limitations is related to the unaccounted- for effect of diseases. Therefore, the goals of this study were to calibrate and validate the CSM CROPGRO-Soybean for the soybean cultivars M-SOY 6101 and MG/BR 46 (Conquista), analyze the performance and the effect of Asian soybean rust on these cultivars under the environmental conditions of Viçosa, Minas Gerais, Brazil. The experimental data for the evaluation, testing, and adjustment of the genetic coefficients for the cultivars, M-SOY 6101 and MG/BR 46 (Conquista), were obtained during the...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: DSSAT; Cropgro-Soybean; Rust epidemics; Models; Model validation; Calibration.
Ano: 2012 URL: http://www.alice.cnptia.embrapa.br/handle/doc/933521
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Validação de um método para a determinação de herbicidas em água. Repositório Alice
QUEIROZ, S. C. do N. de; FERRACINI, V. L.; GOMES, M. A. F.; SANTOS, G. L. dos.
O presente trabalho apresenta um método alternativo para a determinação dos herbicidas hexazinone, tebutiuron, atrazina e diuron em água subterrânea. Os pesticidas são pré-concentrados em cartucho de extração em fase sólida tipo estireno-divinilbenzeno e posteriormente analisados por Cromatografia Líquida de Alta Eficiência (CLAE).
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Método de validação; Herbicida; Água; Herbicides; Water; Model validation; Hexazinone.
Ano: 2005 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1020686
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Validation of a leaf area prediction model proposed for rose Chilean J. Agric. Res.
Fascella,Giancarlo; Darwich,Salem; Rouphael,Youssef.
Leaf area (LA) is a valuable key for evaluating plant growth, therefore accurate, simple, and nondestructive methods for LA determination are important for physiological and agronomic studies. A LA prediction model based on leaf length (L) and width (W) and developed under greenhouse on 14 cultivars of rose (Rosa hybr.*) was validated on a different cultivar of R. hybrida 'Red France' and on a wild rose species (Rosa sempervirens L.) grown under open-field conditions with two light environments: ambient and 50% shade. Comparisons between measured vs. calculated LA using the following model: LA (cm²) = 0.56 + 0.717 LW, showed a high degree of correlation (R² > 0.95) and provided quantitative evidence of the validity of the LA prediction model. Calculated...
Tipo: Journal article Palavras-chave: Leaf length; Leaf width; Rosa hybr; Rosa sempervirens; Light environments; Regression analysis; Model validation.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392013000100011
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