Search Results - "Parameter estimation."

Estimates of direct and maternal (co) variance components of growth traits in Boran cattle by Haile-Mariam, M., Kassa-Mersha, H.

“…Generally, parameter estimates of Boran cattle were within the range of those for other breeds. …”
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Meta-analysis of average estimates of genetic parameters for growth, reproduction and milk production traits in goats by Jembere, T., Dessie, Tadelle, Rischkowsky, Barbara A., Kebede, K., Okeyo Mwai, Ally, Haile, Aynalem

“…The present finding revealed that weighted average ha2, hm2, c2, R, and rg are more reliable for two reasons: estimates of ha2 for some growth traits were more conservative than values from relatively higher number of records and the absence of significant effects of the tested fixed factors on some parameter estimates. However, studies on genetic parameter estimations are required for growth, reproduction, and milk traits in goats.…”
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Advancements in satellite observations of inland and coastal waters: building towards a global validation network by Avouris, D. M., Maciel, F., Sharp, S. L., Craig, S. E., Dekker, A. G., Di Vittorio, C. A., Gardner, J. R., Goldsmith, E., Gossn, J. I., Greb, S. R., Grunert, B. K., Gurlin, D., Jampani, Mahesh, Khan, R. M., Lowin, B., McKinna, L., Mouw, C. B., Ogashawara, I., Calle, S. R., Salls, W., Sánchez-Cabeza, J.-A., Schaeffer, B., Seegers, B. N., Silander, J., Smail, E. A., Wang, M., Werdell, J.

“…Satellite-based sensors are uniquely suited to provide synoptic, system-wide water quality parameter estimates that supplement traditional field-based sampling methods. …”
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Qualitative release and exposure assessment on the risk of HPAI transmission between sector 4 farms and between sector 3 and sector 4 farms in Kenya by Onkundi, D., Bett, Bernard K., Costard, Solenne, Omore, Amos O., Zepeda, C.

“…The level of uncertainty for each risk parameter estimate was described as low, medium or high.…”
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Sheep development program in Egypt by Elshennawy, M.

“…Although characterization of those local breeds has been established and genetic parameters estimated, no effective selection programme has been started.…”
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Evaluation of various mathematical models in describing ruminal degradability of protein sources by Bediye, S., Umunna, N.N., Nsahlai, I.V., Sileshi, Z., Yami, A.

“…Tests of regression coefficients, analysis of residual behavior and ocnsistencies in parameter estimates were adopted for model comparison and validation. …”
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Correlated non-classical measurement errors, ‘second best’ policy inference and the inverse size-productivity relationship in agriculture by Abay, Kibrom A., Abate, Gashaw T., Barrett, Christopher B., Bernard, Tanguy

“…Furthermore, if these measurement errors are correlated, correcting for either one alone can aggravate bias in the parameter estimate of interest relative to ignoring mismeasurement in both variables, a ‘second best’ result with implications for a broad class of economic phenomena of policy interest. …”
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Qualitative Release and Exposure Assessment on the risk of HPAI transmission between sector 4 farms and between sector 3 and sector 4 farms in Kenya by Onkundi, Dennis, Bett, Bernard, Costard, Solenne, Omore, Amos, Zepeda, Cristobal

“…It followed the OIE risk analysis framework where release, exposure and consequence assessments are done successively and their risk parameter estimates combined to obtain an overall risk estimate for a given pathway. …”
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A model of lineage-1 and lineage-2 rinderpest virus transmission in pastoral areas of East Africa by Mariner, Jeffrey C., McDermott, John J., Heesterbeek, J.A.P., Catley, A., Roeder, P.

“…The development of a stochastic, state-transition model of rinderpest transmission dynamics is described using parameter estimates obtained from both laboratory and participatory research. …”
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A method for estimating sampling variances of predicted probabilities from maximum likelihood estimates in logit response function by Rege, J.E.O., Sherington, J.

“…The maximum likelihood parameters estimated in logistic analysis are in terms of a transformation of the original response variable and, although inferences are easily made about the sources of variation in the linearized model using standard procedures applied in regression analysis, the variance-covariance structure of the predicted probabilities obtained following back-transformation of logits is complex and estiamtion of sampling variances normally requires inversion of matrices and taking derivatives of the inverse of the link function evaluated at each prediction point. …”
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A model of contagious bovine pleuropneumonia transmission dynamics in East Africa by Mariner, Jeffrey C., McDermott, John J., Heesterbeek, J.A.P., Thomson, G., Martin, S.W.

“…The model was built using parameter estimates based on data published in the literature and on observations of livestock owners obtained through participatory research. …”
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Approximate sampling variances of maximum-likelihood probability estimates in a logit response function by Rege, J.E.O.

“…The maximum likelihood parameters estimated in logistic analysis are in terms of a transformation of the original response variable and, although inferences are easily made about the sources of variation in the linearized model using standard procedures applied in regression analysis, the variance-covariance structure of the predicted probabilities obtained following back-transformation of logits is complex and estimation of sampling variances normally require inversion of matrices and taking derivatives of the inverse of the link function evaluated at each prediction point. …”
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Genetic parameters, productivity indices and breeding plans for designing community-based goat breeding programs in Ethiopia by Jembere, T.

“…In summary, reliable genetic parameter estimates are presented for genetic improvements in goats. …”
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A revised Tobit procedure for mitigating bias in the presence of non-zero censoring with an application to milk-market participation in the Ethiopian highlands by Holloway, G.J., Nicholson, C., Delgado, Christopher L., Staal, Steven J., Ehui, Simeon K.

“…This literature assumes that the true point of censoring in the data is zero and, when this is not the case, imparts a bias to parameter estimates of the censored regression model. We conjecture that this bias can be significant; affirm this from experiments; and suggest techniques for mitigating this bias using Bayesian procedures. …”
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Attrition in the Kwazulu Natal Income Dynamics Study, 1993-1998 by Maluccio, John A.

“…There is positive selection, and although many of the other parameter estimates are quite similar, a Hausman test rejects the equality of coefficients between the corrected and uncorrected models. …”
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Attrition in the Kwazulu Natal Income Dynamics Study, 1993-1998 by Maluccio, John A.

“…There is positive selection, and although many of the other parameter estimates are quite similar, a Hausman test rejects the equality of coefficients between the corrected and uncorrected models. …”
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Evolution of rice consumption and demand patterns by Gyimah-Brempong, Kwabena, Kuku-Shittu, Oluyemisi

“…The results of the analysis provide parameter estimates of average budget shares (ABS ) and marginal budget shares (MBS), income, and own- and cross-price elasticities, which can be invaluable for informing future rice policies. …”
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Feasibility of pedigree recording and genetic selection in village sheep flocks of smallholder farmers by Gizaw, Solomon, Goshme, Shenkute, Getachew, T., Haile, Aynalem, Rischkowsky, Barbara A., Arendonk, Johan A.M. van, Valle-Zárate, A., Dessie, Tadelle, Okeyo Mwai, Ally

“…In this paper, we evaluated the reliability of pedigree recording in village flocks by comparing genetic parameters estimated from data sets collected in the cooperative village and in a nucleus flock maintained under controlled breeding. …”
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Measurement error mechanisms matter: Agricultural intensification with farmer misperceptions and misreporting by Abay, Kibrom A., Bevis, Leah, Barrett, Christopher B.

“…We show analytically that these alternate data generating processes imply different appropriate regression specifications and have distinct effects on the bias in parameter estimates. We introduce a simple empirical technique to generate unbiased estimates under more general conditions and to apportion measurement error between misreporting and misperceptions in measurement error when one has both self‐reported and objectively measured observations of the same explanatory variable. …”
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Food prices, household income, and resource allocation: Socioeconomic perspectives on their effects on dietary quality and nutritional status by Bouis, Howarth E., Eozenou, Patrick, Rahman, Aminur

“…Not only does this reduce dietary quality, but expenditures for health, sanitation, and education will decline, all of which will have a detrimental effect on health and nutrition outcomes.To provide some perspectives on the role of major socioeconomic factors in driving health and nutrition outcomes.We use demand elasticity parameters estimated from household-level survey data to simulate an increase in food prices, which is then mapped into energy and nutrient intakes. …”
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