Relevant bibliographies by topics / Ratio estimators

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Ratio estimators'

Author: Grafiati
Published: 8 September 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Ratio estimators.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Ratio estimators"

1

Ekiz, Meltem, and Osman Ufuk Ekiz. "Modelling Tap Water Consumer Ratio." Mathematics 8, no. 9 (September 10, 2020): 1557. http://dx.doi.org/10.3390/math8091557.

Full text
Abstract:
Increasing population and the rising air temperatures are known as factors that cause water depletion in the watersheds. Therefore, it is important to accurately predict the future ratios of tap water consumers using the same watershed to the population living in the specified area, to produce better water policies and to take the necessary measures. Predictions can be made by a growth curve model (GCM). Parameter estimations of the GCM are usually based on the ordinary least square (OLS) estimator. However, the outlier presence affects the estimations and the predictions, which are obtained by using the estimated model. The present article attempts to construct first- and third-order GCMs with robust least median square (LMS) and M estimators to make short-term predictions of ratios of tap water consumers. According to the findings, parameter estimations of the models, the outliers, and the predictions vary with respect to the estimators. The M estimator for short-term predictions is suggested for use, due to its robustness against outlier points.
APA, Harvard, Vancouver, ISO, and other styles
2

Ijaz, Muhammad, Syed Muhammad Asim, Atta ullah, and Ibrahim Mahariq. "Flexible Robust Regression-Ratio Type Estimators and Its Applications." Mathematical Problems in Engineering 2022 (September 28, 2022): 1–6. http://dx.doi.org/10.1155/2022/8977392.

Full text
Abstract:
In real-world situations, the data set under examination may contain uncommon noisy measurements that unreasonably affect the data’s outcome and produce incorrect model estimates. Practitioners employed robust-type estimators to reduce the weight of the noisy measurements in a data set in such a scenario. Using auxiliary information that will produce reliable estimates, we have looked at a few flexible robust-type estimators in this study. In order to estimate the population mean, this study presents unique flexible robust regression type ratio estimators that take into account the data from the midrange and interdecile range of the auxiliary variables. Up to the first order of approximate computation, the bias and mean square were calculated. In order to compare the flexibility of the proposed estimator to those of the existing estimators, theoretical conditions were also obtained. We took into account data sets containing outliers for empirical computation, and it was found that the suggested estimators produce results with higher precision than the existing estimators.
APA, Harvard, Vancouver, ISO, and other styles
3

Chadyšas, V., and D. Krapavickaitė. "Investigation of Accuracy of a Calibrated Estimator of a Ratio by Modelling." Nonlinear Analysis: Modelling and Control 10, no. 4 (October 25, 2005): 333–42. http://dx.doi.org/10.15388/na.2005.10.4.15113.

Full text
Abstract:
Estimator of finite population parameter – ratio of totals of two variables – is investigated by modelling in the case of simple random sampling. Traditional estimator of the ratio is compared with the calibrated estimator of the ratio introduced by Plikusas [1]. The Taylor series expansion of the estimators are used for the expressions of approximate biases and approximate variances [2]. Some estimator of bias is introduced in this paper. Using data of artificial population the accuracy of two estimators of the ratio is compared by modelling. Dependence of the estimates of mean square error of the estimators of the ratio on the correlation coefficient of variables which are used in the numerator and denominator, is also shown in the modelling.
APA, Harvard, Vancouver, ISO, and other styles
4

Malik, Sachin, and Rajesh Singh. "Some Improved Multivariate-Ratio-Type Estimators Using Geometric and Harmonic Means in Stratified Random Sampling." ISRN Probability and Statistics 2012 (August 26, 2012): 1–7. http://dx.doi.org/10.5402/2012/509186.

Full text
Abstract:
Auxiliary variable is commonly used in survey sampling to improve the precision of estimates. Whenever there is auxiliary information available, we want to utilize it in the method of estimation to obtain the most efficient estimator. In this paper using multiauxiliary information we have proposed estimators based on geometric and harmonic mean. It was also shown that estimators based on harmonic mean and geometric mean are less biased than Olkin (1958) and Singh (1967) estimators under certain conditions. However, the MSE of Olkin (1958) estimator and geometric and harmonic estimators are same up to the first order of approximations.
APA, Harvard, Vancouver, ISO, and other styles
5

Chami, Peter S., Bernd Sing, and Doneal Thomas. "A Two-Parameter Ratio-Product-Ratio Estimator Using Auxiliary Information." ISRN Probability and Statistics 2012 (October 14, 2012): 1–15. http://dx.doi.org/10.5402/2012/103860.

Full text
Abstract:
We propose a two-parameter ratio-product-ratio estimator for a finite population mean in a simple random sample without replacement following the methodology in the studies of Ray and Sahai (1980), Sahai and Ray (1980), A. Sahai and A. Sahai (1985), and Singh and Espejo (2003).The bias and mean squared error of our proposed estimator are obtained to the first degree of approximation. We derive conditions for the parameters under which the proposed estimator has smaller mean squared error than the sample mean, ratio, and product estimators. We carry out an application showing that the proposed estimator outperforms the traditional estimators using groundwater data taken from a geological site in the state of Florida.
APA, Harvard, Vancouver, ISO, and other styles
6

Cahalan, Jennifer A., Jason Gasper, and Jennifer Mondragon. "Catch estimation in the federal trawl fisheries off Alaska: a simulation approach to compare the statistical properties of three trip-specific catch estimators." Canadian Journal of Fisheries and Aquatic Sciences 72, no. 7 (July 2015): 1024–36. http://dx.doi.org/10.1139/cjfas-2014-0347.

Full text
Abstract:
Quantifying catch has been recognized worldwide as a critical component in fisheries management. Assessment of discard is challenging because of the requirement for at-sea observation, which is both logistically difficult and costly to fishery agencies. Statistical estimators using robust sampling methods may yield accurate and imprecise estimates given the variability associated with many at-sea discard species and inability for agencies to obtain high sampling fractions. However, biased estimates occur if an inappropriate estimator is used. Using Alaska trawl fisheries as an example, we investigated the statistical properties and implementation issues for three commonly used estimators: the ratio estimator; a simple mean estimator; and a deterministic imputation method currently in use in federal fisheries off Alaska. We used a simulation approach to evaluate the performance of these estimators to estimate trip-specific catch. Several statistical properties were evaluated: bias of the estimators, variability of the estimators, and accuracy of the variance estimators. The simple mean estimator had the best performance for vessels landing catch at shoreside processors. The choice of estimator was less clear for vessels processing catch, owing to sensitivity associated with species composition and implementation issues for the simple mean and ratio estimators.
APA, Harvard, Vancouver, ISO, and other styles
7

Shaheen, Nazia, Muhammad Nouman Qureshi, Osama Abdulaziz Alamri, and Muhammad Hanif. "Optimized inferences of finite population mean using robust parameters in systematic sampling." PLOS ONE 18, no. 1 (January 23, 2023): e0278619. http://dx.doi.org/10.1371/journal.pone.0278619.

Full text
Abstract:
In this article, we have proposed a generalized estimator for mean estimation by combining the ratio and regression methods of estimation in the presence of auxiliary information using systematic sampling. We incorporated some robust parameters of the auxiliary variable to obtain precise estimates of the proposed estimator. The mathematical expressions for bias and mean square error of proposed the estimator are derived under large sample approximation. Many other generalized ratio and product-type estimators are obtained from the proposed estimator using different choices of scalar constants. Some special cases are also discussed in which the proposed generalized estimator reduces to the usual mean, classical ratio, product, and regression type estimators. Mathematical conditions are obtained for which the proposed estimator will perform more precisely than the challenging estimators mentioned in this article. The efficiency of the proposed estimator is evaluated using four populations. Results showed that the proposed estimator is efficient and useful for survey sampling in comparison to the other existing estimators.
APA, Harvard, Vancouver, ISO, and other styles
8

Subramani, J., and G. Kumarapandiyan. "A Class of Modified Ratio Estimators for Estimation of Population Variance." Journal of Applied Mathematics, Statistics and Informatics 11, no. 1 (May 1, 2015): 91–114. http://dx.doi.org/10.1515/jamsi-2015-0006.

Full text
Abstract:
Abstract In this paper we have proposed a class of modified ratio type variance estimators for estimation of population variance of the study variable using the known parameters of the auxiliary variable. The bias and mean squared error of the proposed estimators are obtained and also derived the conditions for which the proposed estimators perform better than the traditional ratio type variance estimator and existing modified ratio type variance estimators. Further we have compared the proposed estimators with that of the traditional ratio type variance estimator and existing modified ratio type variance estimators for certain natural populations.
APA, Harvard, Vancouver, ISO, and other styles
9

Rather, Khalid Ul Islam, Eda Gizem Koçyiğit, Ronald Onyango, and Cem Kadilar. "Improved regression in ratio type estimators based on robust M-estimation." PLOS ONE 17, no. 12 (December 12, 2022): e0278868. http://dx.doi.org/10.1371/journal.pone.0278868.

Full text
Abstract:
In this article, a new robust ratio type estimator using the Uk’s redescending M-estimator is proposed for the estimation of the finite population mean in the simple random sampling (SRS) when there are outliers in the dataset. The mean square error (MSE) equation of the proposed estimator is obtained using the first order of approximation and it has been compared with the traditional ratio-type estimators in the literature, robust regression estimators, and other existing redescending M-estimators. A real-life data and simulation study are used to justify the efficiency of the proposed estimators. It has been shown that the proposed estimator is more efficient than other estimators in the literature on both simulation and real data studies.
APA, Harvard, Vancouver, ISO, and other styles
10

Payandeh, Bijan, and Alan R. Ek. "Distance methods and density estimators." Canadian Journal of Forest Research 16, no. 5 (October 1, 1986): 918–24. http://dx.doi.org/10.1139/x86-163.

Full text
Abstract:
The relative performance of five distance–density estimators was evaluated for the n-tree circular, semicircular, and strip plots on several simulated and natural tree populations. Results indicate that for the n-tree circular plot, the ratio estimator performed very well for most populations examined and for n > 10. The performance of both the maximum likelihood and first moment estimators was affected to a great degree by the spatial pattern of the populations, but they performed satisfactorily for the random and uniform populations and for large n values (i.e., n > 10). Smaltschinski's estimator resulted in nearly bias-free estimates for nonaggregated populations and for all n, but performed poorly otherwise. The generalized Prodan estimator performed well for the random population, but overestimated the density otherwise. The relative performance of all estimators for the n-tree semicircular plot was quite similar to that of estimators for the n-tree circular plot, except that the former tended to produce lower density estimates. For n-tree strip plots, the generalized Prodan and the ratio estimator performed very well for the nonaggregated populations and for n > 10. All other estimators resulted in density estimates lower than those for n-tree circular and semicircular plots.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Ratio estimators"

1

Chen, Dandan. "Amended Estimators of Several Ratios for Categorical Data." Digital Commons @ East Tennessee State University, 2006. https://dc.etsu.edu/etd/2218.

Full text
Abstract:
Point estimation of several association parameters in categorical data are presented. Typically, a constant is added to the frequency counts before the association measure is computed. We will study the accuracy of these adjusted point estimators based on frequentist and Bayesian methods respectively. In particular, amended estimators for the ratio of independent Poisson rates, relative risk, odds ratio, and the ratio of marginal binomial proportions will be examined in terms of bias and mean squared error.
APA, Harvard, Vancouver, ISO, and other styles
2

Ladak, Al-Karim Madatally. "Resampling-based variance estimators in ratio estimation with application to weigh scaling." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29195.

Full text
Abstract:
Weigh scaling is a method of estimating the total volume of timber harvested from a given region. The implementation of statistical sampling techniques in weigh scaling is described, along with related issues. A review of ratio estimators, along with variance estimators of the classical ratio estimator is conducted. The estimation of the variance of the estimated total volume is considered using jackknife- and bootstrap-based variance estimators. Weighted versions of the jackknife and bootstrap variance estimators are derived using influence functions and Fisher Information matrices. Empirical studies of analytic and resampling-based variance estimators are conducted, with particular emphasis on small sample properties and on robustness with respect to both the homoscedastic variance and zero-intercept population characteristics. With a squared error loss function, the resampling-based variance estimators are shown to perform very well at all sample sizes in finite populations with normally distributed errors. These estimators are found to have small negative biases for small sample sizes and to be robust with respect to heteroscedasticity.
Science, Faculty of
Statistics, Department of
Graduate
APA, Harvard, Vancouver, ISO, and other styles
3

Hattaway, James T. "Parameter Estimation and Hypothesis Testing for the Truncated Normal Distribution with Applications to Introductory Statistics Grades." Diss., CLICK HERE for online access, 2010. http://contentdm.lib.byu.edu/ETD/image/etd3412.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Mazzarella, Gianluca. "Combining Jump and Kink ratio estimators in Regression Discontinuity Designs, with an application to the causal effect of retirement on well-being." Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424749.

Full text
Abstract:
Regression Discontinuity Design (RDD) is one of the most popular designs in the field of causal inference in nonexperimental settings. It is based on the idea that the treatment is (totally or partially) determined by a threshold point of an observed continuous variable. When the treatment is just partially determined by that variable, it is usu- ally defined fuzzy RDD. In this setting, given a certain outcome, the only effect that one is able to identify is the Average Treatment Effect (ATE) for the subpopulation of the Compliers at the threshold point. The ATE could be obtained by the ratio between the discontinuity at the threshold point in the average of the observed outcome divided by the discontinuity in the treatment probability. This thesis explores, from a methodological and empirical perspective, how the change of slope at the threshold point is informative for the estimate of the parameter of interest. Starting from the changes of the eligibility criterion for retirement that took place in Italy in the ’90s we propose an alternative estimator, based on Instrumental Variables, that is a combination of the discontinuity and the change of slope. Furthermore we provide a simulation study to compare the efficiency of the different estimators. Then we analyze the effects of retirement on the subjective well–being. Finally we generalize the results using the Two Sample Instrumental Variable estimator, in order to improve the efficiency of estimates based on administrative data and to con- struct delayed outcomes for the same cohorts.
Il Regression Discontinuity Design è una delle più diffuse tecniche nell'ambito dell’inferenza causale nei processi quasi-sperimentali. È basata sull'idea che l'esposizione ad un trattamento sia (parzialmente o totalmente) stabilita da un punto di soglia di una variabile continua e osservabile. Quando l'esposizione al trattamento è solo parzialmente stabilita da questa variabile, si è solito definirlo fuzzy Regression Discontinuity Design. In questo contesto, dato un determinato outcome di interesse, è possibile identificare soltanto l’effetto medio del trattamento per la sotto-popolazione dei Compliers. Tale effetto può essere ottenuto dal rapporto tra la discontinuità nel punto di soglia nella media dell'outcome divisa per la discontinuità nella probabilità di esposizione al trattamento. La tesi esamina, da un punto di vista metodologico e empirico, come possano essere informativi per la stima del parametro di interesse i cambiamenti di pendenza nel punto di soglia. Partendo dalle modifiche nei criteri di ammissibilità al pensionamento avvenuti in Italia a partire dagli anni '90, abbiamo proposto uno stimatore, basato sulla logica delle Variabili Strumentali, che è una combinazione della discontinuità e del cambiamento di pendenza. In seguito abbiamo proposto uno studio di simulazione per confrontare l'efficienza dei diversi stimatori. Successivamente abbiamo analizzato gli effetti del pensionamento sulla soddisfazione personale percepita. Infine abbiamo generalizzato, usando lo stimatore a Variabili Strumentali su Due Campioni per migliorare l'efficienza delle stime con dati amministrativi o per costruire outcome successivi al pensionamento.
APA, Harvard, Vancouver, ISO, and other styles
5

Hariharan, S. "Channel estimators for HF radio links." Thesis, Loughborough University, 1988. https://dspace.lboro.ac.uk/2134/6733.

Full text
Abstract:
The thesis is concerned with the estimation of the sampled impulse-response (SIR), of a time-varying HF channel, where the estimators are used in the receiver of a 4800 bits/s, quaternary phase shift keyed (QPSK) system, operating at 2400 bauds with an 1800 Hz carrier. T= FIF modems employing maximum-likelihood detectors at the receiver require accurate knowledge of the SIR of the channel. With this objective in view, the thesis considers a number of channel estimation techniques, using an idealised model of the data transmission system. The thesis briefly describes the ionospheric propagation medium and the factors affecting the data transmission over BF radio. It then presents an equivalent baseband model of the I-IF channel, that has three separate Rayleigh fading paths (sky waves), with a 2Hz frequency spread and transmission delays of 0,1.1 and 3 milliseconds relative to the first sky wave. Estimation techniques studied are, the Gradient estimator, the Recursive leastsquares (RLS) Kalman estimator, the Adaptive channel estimators, the Efficient channel estimator ( that takes into account prior knowledge of the number of fading paths in the channel ), and the Fast Transversal Filter (F-FF), estimator (which is a simplified form of the Kalman estimator). Several new algorithms based on the above mentioned estimation techniques are also proposed. Results of the computer simulation tests on the performance of the estimators, over a typical worst channel, are then presented. The estimators are reasonably optimized to achieve the minimum mean-square estimation error and adequate allowance has been made for stabilization before the commencement of actual measurements. The results, therefore, represent the steady-state performance of the estimators. The most significant result, obtained in this study, is the performance of the Adaptive estimator. When the characteristics of the channel are known, the Efficient estimators have the best performance and the Gradient estimators the poorest. Kalman estimators are the most complex and Gradient estimators are the simplest. Kalman estimators have a performance rather similar to that of Gradient estimators. In terms of both performance and complexity, the Adaptive estimator lies between the Kalman and Efficient estimators. FTF estimators are known to exhibit numerical instability, for which an effective stabilization technique is proposed. Simulation tests have shown that the mean squared estimation error is an adequate measurement for comparison of the performance of the estimators.
APA, Harvard, Vancouver, ISO, and other styles
6

Gendron, Paul John. "A comparison of digital beacon receiver frequency estimators." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09292009-020307/.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Sousa, Rita Cristina Pinto de. "Parameter estimation in the presence of auxiliary information." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11295.

Full text
Abstract:
Dissertação para obtenção do Grau de Doutora em Estatística e Gestão de Risco, Especialidade em Estatística
In survey research, there are many situations when the primary variable of interest is sensitive. The sensitivity of some queries can give rise to a refusal to answer or to false answers given intentionally. Survey can be conducted in a variety of settings, in part dictated by the mode of data collection, and these settings can differ in how much privacy they offer the respondent. The estimates obtained from a direct survey on sensitive questions would be subject to high bias. A variety of techniques have been used to improve reporting by increasing the privacy of the respondents. The Randomized Response Technique (RRT), introduced byWarner in 1965, develops a random relation between the individual’s response and the question. This technique provides confidentiality to respondents and still allows the interviewers to estimate the characteristic of interest at an aggregate level. In this thesis we propose some estimators to improve the mean estimation of a sensitive variable based on a RRT by making use of available non-sensitive auxiliary information. In the first part of this thesis we present the ratio and the regression estimators as well as some generalizations in order to study the gain in the estimation over the ordinary RRT mean estimator. In chapters 4 and 5 we study the performance of some exponential type estimators, also based on a RRT. The final part of the thesis illustrates an approach to mean estimation in stratified sampling. This study confirms some previous results for a different sample design. An extensive simulation study and an application to a real dataset are done for all the study estimators to evaluate their performance. In the last chapter we present a general discussion referring to the main results and conclusions as well as showing an application to a real dataset which compares the performance of study estimators.
APA, Harvard, Vancouver, ISO, and other styles
8

Winnett, Angela Susan. "Flexible estimators of hazard ratios for exploratory and residual analysis." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312945.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Brownridge, Alyce Mahan. "Comparisons of lysimetric and Bowen ratio estimates of evapotranspiration." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/191841.

Full text
Abstract:
Two sets of Bowen ratio and lysimeter measurements of evapotranspiration (ET) were compared for a field of winter wheat in Phoenix, Arizona. Daytime data for ten days of clear skies were examined. Daily lysimeter ET (LET) generally exceeded Bowen ratio ET (BRET). Advective cases were compared with lapse cases. For one set of lysimeter and Bowen ratio measurements, average LET was 10% more than BRET during advective conditions, while average LET and BRET were equal during lapse conditions. Results for the other pair of measurements were less conclusive due to unresolved lysimeter problems, with average LET 13% more than BRET during advection, and average LET 13% less than BRET during lapse conditions. These results suggest that the assumption of equal eddy diffusivities for heat and vapor caused BRET to underestimate evapotranspiration during advection. The Bowen ratio, wind speed, and wind direction were identified as possible variables for correcting BRET underestimation.
APA, Harvard, Vancouver, ISO, and other styles
10

Manno, Michael S. "An evaluation of the odds ratio as an estimator of vaccine efficacy." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0001/MQ28747.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Ratio estimators"

1

Cecchetti, Stephen G. Structural estimates of the U.S. sacrifice ratio. [New York, N.Y.]: Federal Reserve Bank of New York, 1999.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Willem W. S. Van Hees. A comparison of two estimates of standard error for a ratio-of-means estimator for a mapped-plot sample design in Southeast Alaska. Portland, OR: U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Research Station, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Manno, Michael S. An evaluation of the odds ratio as an estimator of vaccine efficacy. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1999.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Seale, David Andrew. A statistical model of microarray images and an estimator of gene expression ratio. Ottawa: National Library of Canada, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Godfrey, Matthew Howland. Sex ratios of sea turtle hatchlings: Direct and indirect estimates. Ottawa: National Library of Canada = Bibliothèque nationale du Canada, 1997.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

J, Musgrave, and United States. National Aeronautics and Space Administration., eds. A neural network-based estimator for the mixture ratio of the space shuttle main engine. [Washington, DC]: National Aeronautics and Space Administration, 1992.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

J, Musgrave, and United States. National Aeronautics and Space Administration., eds. A neural network-based estimator for the mixture ratio of the space shuttle main engine. [Washington, DC]: National Aeronautics and Space Administration, 1992.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

L, Musgrave Jeffrey, and United States. National Aeronautics and Space Administration., eds. A neural network-based estimator for the mixture ratio of the space shuttle main engine. [Washington, DC]: National Aeronautics and Space Administration, 1992.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Oliveira-Martins, Joaquim. Mark-up ratios in manufacturing industries: Estimates for 14 OECD countries. Paris: OECD, 1996.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

A, Schowengerdt Robert, and Research Institute for Advanced Computer Science (U.S.), eds. The effect of lossy image compression on image classification. [Moffett Field, Calif.]: Research Institute for Advanced Computer Science, NASA Ames Research Center, 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Ratio estimators"

1

de Vries, Pieter G. "Ratio Estimators in Simple Random Sampling." In Sampling Theory for Forest Inventory, 56–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71581-5_3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

de Vries, Pieter G. "Ratio Estimators in Stratified Random Sampling." In Sampling Theory for Forest Inventory, 75–87. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71581-5_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Kubokawa, T., and M. S. Srivastava. "Double shrinkage estimators of ratio of variances." In Multidimensional Statistical Analysis and Theory of Random Matrices, edited by A. K. Gupta and V. L. Girko, 139–54. Berlin, Boston: De Gruyter, 1996. http://dx.doi.org/10.1515/9783110916690-013.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Pigeot, Iris. "Jackknifing Estimators of a Common Odds Ratio from Several 2×2 Tables." In Lecture Notes in Economics and Mathematical Systems, 203–12. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-48850-4_26.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Andersen, Per Kragh. "Hazard Ratio Estimator." In International Encyclopedia of Statistical Science, 624–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-04898-2_284.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Ghosh, Malay, and Robert M. Baskin. "On the Robustness of Bayes Estimators of the Variance Ratio in Balanced One-Way ANOVA Models with Covariates." In Statistical Theory and Applications, 217–31. New York, NY: Springer New York, 1996. http://dx.doi.org/10.1007/978-1-4612-3990-1_18.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Greenhouse, Samuel W., and Joseph L. Gastwirth. "The Joint Asymptotic Distribution of the Maximum Likelihood and Mantel-Haenszel Estimators of the Common Odds Ratio in k 2 x 2 Tables." In Modelling and Prediction Honoring Seymour Geisser, 264–73. New York, NY: Springer New York, 1996. http://dx.doi.org/10.1007/978-1-4612-2414-3_16.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Vaz, Afonso, Rafael Izbicki, and Rafael Bassi Stern. "Prior Shift Using the Ratio Estimator." In Springer Proceedings in Mathematics & Statistics, 25–35. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-91143-4_3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Ivanov, Boris A. "Mars/Moon Cratering Rate Ratio Estimates." In Space Sciences Series of ISSI, 87–104. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-017-1035-0_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Kontizas, M., E. Kontizas, and A. Dapergolas. "New Estimates for the C/M Ratio." In Astronomy, Cosmology and Fundamental Physics, 431–32. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-0965-6_39.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Ratio estimators"

1

Eckman, David J., and M. Ben Feng. "GREEN SIMULATION OPTIMIZATION USING LIKELIHOOD RATIO ESTIMATORS." In 2018 Winter Simulation Conference (WSC). IEEE, 2018. http://dx.doi.org/10.1109/wsc.2018.8632169.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Glynn, P. W. "Likelihood ratio derviative estimators for stochastic systems." In the 21st conference. New York, New York, USA: ACM Press, 1989. http://dx.doi.org/10.1145/76738.76785.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Yazici, Murat. "The weighted least squares ratio (WLSR) method to M-estimators." In 2016 SAI Computing Conference (SAI). IEEE, 2016. http://dx.doi.org/10.1109/sai.2016.7556018.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Sharma, Sumiti, and Sangeeta Malik. "Some improved quadratic ratio and product type linear regression estimators." In PROCEEDING OF INTERNATIONAL CONFERENCE ON FRONTIERS OF SCIENCE AND TECHNOLOGY 2021. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0115261.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Hiraoka, Kazuyuki, Toshihiko Hamada, and Gen Hori. "Estimators for unnormalized statistical models based on self density ratio." In ICASSP 2014 - 2014 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). IEEE, 2014. http://dx.doi.org/10.1109/icassp.2014.6854458.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Wild, Walter J. "Optimal Estimators for Astronomical Adaptive Optics." In Adaptive Optics. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/adop.1996.athb.1.

Full text
Abstract:
An adaptive optics system is a closed-loop servo control system that seeks to maximize PSF Strehl ratio performance by minimizing wavefront distortions. The wavefront is sampled over discrete subapertures and the local slopes are used to estimate the instantaneous wavefront shape which is then used to drive a deformable mirror with a discrete array of actuators. The temporal and spatial performance of the system is embodied in a single mathematical descriptor of the form Γ is a covariance matrix of the error between the atmosphere phase φ(ti+1) at time ti+1 and the deformable mirror figure, ϕdm(ti), derived from measurements at the previous time ti. Boldface quantities are vectors and matrices. The phase reflecting off the mirror is φ(ti+1) – ϕ(ti), presently assuming that ϕdm(ti)≈ϕ(ti), where ϕ(ti) is the estimated wavefront phase. Covariance matrices are a powerful mathematical tool because they contain information, in an ensemble average sense, about the sources of error and correlations present in the system. From Γ, the Strehl ratio, the MTF, time-delay, etc., can be computed. The Strehl ratio in the Marechal approximation is S ~ exp(–σ2), where σ2=Tr(Γ) /Na, for Na actuators within the pupil.
APA, Harvard, Vancouver, ISO, and other styles
7

Winick, Kim A. "Cramer-Rao lower bounds on the performance of CCD optical position estimators." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.fi2.

Full text
Abstract:
The problem of optically estimating an object’s position using a charge coupled device (CCD) array composed of square pixels Δx on a side is analyzed. The object’s image spot at the CCD is assumed to have a Gaussian intensity profile with a 1/e point at a radial distance of 2 σ s from the peak, and the CCD noise is modeled as Poisson distributed dark current shot noise. A 2-D Cramer-Rao bound is developed and used to determine a lower limit for the mean-square error of any unbiased position estimator, and the maximum likelihood estimator is also derived. For the 1-D position estimation problem the lower bound is shown to be minimum for a pixel-to-image size ratio Δx/σ s of between 1 and 2 over a wide range of signal-to-noise ratios. Similarly for the 2-D problem, the optimum ratio is shown to lie between 1.5 and 2.5. As is customary in direct detection systems, it is also observed that the lower bound is a function of both the signal power and noise power separately and not just their ratio. Finally at high signal-to-noise ratios, the maximum likelihood estimator is shown to be independent of the signal and noise powers.
APA, Harvard, Vancouver, ISO, and other styles
8

Conan, Jean-Marc, Vincent Michau, and Gerard Rousset. "Signal-to-noise ratio and bias of various deconvolution from wavefront sensing estimators." In SPIE's 1996 International Symposium on Optical Science, Engineering, and Instrumentation, edited by Christopher Dainty and Luc R. Bissonnette. SPIE, 1996. http://dx.doi.org/10.1117/12.254206.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Zheng, Chengshi, Xiaodong Li, Andreas Schwarz, and Walter Kellermann. "Statistical analysis and improvement of coherent-to-diffuse power ratio estimators for dereverberation." In 2016 IEEE International Workshop on Acoustic Signal Enhancement (IWAENC). IEEE, 2016. http://dx.doi.org/10.1109/iwaenc.2016.7602931.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Gopal, Lenin, and Moh Lim Sim. "Performance Analysis of Signal-to-Noise Ratio Estimators in AWGN and Fading Channels." In 2nd Malaysia Conferenced on Photonics (MCP). IEEE, 2008. http://dx.doi.org/10.1109/nctt.2008.4814291.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Ratio estimators"

1

Glynn, Peter W. Likelihood Ratio Derivative Estimators for Stochastic Systems. Fort Belvoir, VA: Defense Technical Information Center, August 1989. http://dx.doi.org/10.21236/ada213787.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Panek, Jeffrey, Adrian Huth, James McCarthy, and Alan Krol. PR-312-18208-E02 PRCI White Paper PVMRM Theoretical Issues and Recommended Solutions. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 2021. http://dx.doi.org/10.55274/r0012113.

Full text
Abstract:
This white paper demonstrates that AERMOD contains formulation errors and does not currently provide accurate NOx estimates for sources (e.g., natural gas compressor stations) with shorter stacks. The white paper also demonstrates that a new building downwash theory (PRIME2) does provide better agreement with NOx observations than AERMOD's PRIME algorithms. In addition, the white paper shows that PVMRM does not provide accurate estimates of the NO2/NOx ratio as confirmed by Panek et al. (2020) who showed poor agreement between predicted and observed NO2/NOx ratios. The paper concludes that the basic theory in PVMRM is sound, but some underlying simplifying assumptions contribute to model performance issues.
APA, Harvard, Vancouver, ISO, and other styles
3

Margraf, J. D., and T. A. Dunn. Spent Fuel Ratio Estimates from Numerical Models in ALE3D. Office of Scientific and Technical Information (OSTI), August 2016. http://dx.doi.org/10.2172/1289356.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

van Hees, Willem W. S. A comparison of two estimates of standard error for a ratio-of-means estimator for a mapped-plot sample design in southeast Alaska. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, 2002. http://dx.doi.org/10.2737/pnw-rn-532.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Kott, Phillip S. Better Coverage Intervals for Estimators from a Complex Sample Survey. RTI Press, February 2020. http://dx.doi.org/10.3768/rtipress.2020.mr.0041.2002.

Full text
Abstract:
Coverage intervals for a parameter estimate computed using complex survey data are often constructed by assuming the parameter estimate has an asymptotically normal distribution and the measure of the estimator’s variance is roughly chi-squared. The size of the sample and the nature of the parameter being estimated render this conventional “Wald” methodology dubious in many applications. I developed a revised method of coverage-interval construction that “speeds up the asymptotics” by incorporating an estimated measure of skewness. I discuss how skewness-adjusted intervals can be computed for ratios, differences between domain means, and regression coefficients.
APA, Harvard, Vancouver, ISO, and other styles
6

Yu, Yipin, Duoting Tan, Dan Sheng, Liqin Zhong, Zhixi Hu, and Hao Liang. Neutrophil-to-lymphocyte ratio as a prognostic predictor for heart failure patients: a systematic review and meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, March 2022. http://dx.doi.org/10.37766/inplasy2022.3.0062.

Full text
Abstract:
Review question / Objective: This study aimed to evaluate the relationship between NLR and in-hospital or long-term prognosis of patients with heart failure by meta-analysis. Eligibility criteria: Inclusion criteria: (1) Patients with heart failure who underwent NLR measurement ;the study types were prospective cohort study or retrospective cohort study; and (3) risk estimates of association between NLR levels and heart failure related events occurring during hospital or follow-up were studied experimentally. Case reports, reviews, animal studies, conference proceedings, letters to editors, abstract only and duplicated studies were excluded.
APA, Harvard, Vancouver, ISO, and other styles
7

Liu, Jing, Yuanmei Chen, Die Liu, Fang Ye, Qi Sun, Qiang Huang, Jing Dong Dong, Tao Pei, Yuan He, and Qi Zhang. Prenatal exposure to particulate matter and term low birth weight：systematic review and meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, August 2022. http://dx.doi.org/10.37766/inplasy2022.8.0064.

Full text
Abstract:
Review question / Objective: To assess the effects of particulate matter exposure during various periods of pregnancy on low birth weight and term low birth weight. Population:pregnant women and their singleton live-births; Exposure: maternal exposure to ambient PM2.5 and PM10 during the entire pregnancy or each trimesters were estimated based on ground-level atmospheric pollution monitoring stations or validated exposure models (μg/m3 ); Comparator(s): risk estimates were presented as hazard ratios (HRs) or odds ratios (ORs) and their 95% confidence intervals (95% CI) with per specific increment in PM2.5; Outcomes: term LBW(≥37weeks and<2500g) or LBW(<2500g)were defined as a dichotomous variables.
APA, Harvard, Vancouver, ISO, and other styles
8

Stuedlein, Armin, Ali Dadashiserej, and Amalesh Jana. Models for the Cyclic Resistance of Silts and Evaluation of Cyclic Failure during Subduction Zone Earthquakes. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, April 2023. http://dx.doi.org/10.55461/zkvv5271.

Full text
Abstract:
This report describes several advances in the cyclic failure assessment of silt soils with immediate and practical benefit to the geotechnical earthquake engineering profession. First, a database of cyclic loading test data is assembled, evaluated, and used to assess trends in the curvature of the CRR-N (cyclic resistance ratio - the number of equivalent cycles) relationship. This effort culminated in a plasticity index-dependent function which can be used to estimate the exponent b in the power law describing cyclic resistance, and may be used to estimate the cyclic resistance of silt soils as well as the number of equivalent loading cycles anticipated for subduction zone earthquakes. Statistical models for the cyclic resistance ratio and cyclic strength ratio are presented in this report. The SHANSEP (Stress History and Normalized Soil Engineering Properties)-inspired functional form of these models have been trained and tested against independent datasets and finalized using a combined dataset to provide reasonable estimates of resistance based on the available data. These models can be used to provide provisional estimates of the CRR-N and cyclic strength ratio power laws for cyclic shear strain failure criteria ranging from 1 to 10%, within certain stated limitations. The ground motion records within the NGA Subduction Project which have been released to the public to-date are implemented to examine the role of subduction zone earthquake characteristics on the number of equivalent loading cycles for a wide range of soils with exponents b ranging from 0.05 (moderate plasticity silt and clay) to 0.35 (dense sand). This analysis shows that the number of loading cycles for a given magnitude subduction zone earthquake is larger than those previously computed, whereas the corresponding magnitude scaling factors for use with the Simplified Method span a smaller range as a result of the ground motion characteristics. Owing to the large variability in the computed equivalent number of loading cycles, consideration of the uncertainty is emphasized in forward analyses. The work described herein may be used to estimate cyclic resistance of intact non-plastic and plastic silt soils and corresponding factor of safety against cyclic failure for a range in cyclic shear strain failure criteria, to plan cyclic laboratory testing programs, and to calibrate models for use in site response and nonlinear deformation analyses in the absence of site-specific cyclic test data. As with any empirical approach, the models presented herein should be revised when additional, high-quality cyclic testing data become available.
APA, Harvard, Vancouver, ISO, and other styles
9

Hill, Samuel, Yothin Jinjarak, and Donghyun Park. Buoyant or Sinking? Tax Revenue Performance and Prospects in Developing Asia. Asian Development Bank, May 2022. http://dx.doi.org/10.22617/wps220182-2.

Full text
Abstract:
This paper examines tax revenue mobilization in developing Asia before the coronavirus disease (COVID-19) pandemic and in 2020. Analysis suggests that short- and long-run tax buoyancy in developing Asia were close to one before COVID-19, indicating fiscal sustainability. The study estimates that in 2020 the pandemic caused these economies to lose average excess tax revenue equal to half a percentage point of 2019 GDP. It also finds that tax-to-GDP ratios are projected to improve toward 2030 in a majority of developing Asian economies, other things held constant.
APA, Harvard, Vancouver, ISO, and other styles
10

Rosero-Bixby, Luis, and Tim Miller. The mathematics of the reproduction number R for Covid-19: A primer for demographers. Verlag der Österreichischen Akademie der Wissenschaften, December 2021. http://dx.doi.org/10.1553/populationyearbook2022.res1.3.

Full text
Abstract:
The reproduction number R is a key indicator used to monitor the dynamics of Covid-19 and to assess the effects of infection control strategies that frequently have high social and economic costs. Despite having an analog in demography’s “net reproduction rate” that has been routinely computed for a century, demographers may not be familiar with the concept and measurement of R in the context of Covid-19. This article is intended to be a primer for understanding and estimating R in demography. We show that R can be estimated as a ratio between the numbers of new cases today divided by the weighted average of cases in previous days. We present two alternative derivations for these weights based on how risks have changed over time: constant vs. exponential decay. We then provide estimates of these weights, and demonstrate their use in calculating R to trace the course of the first pandemic year in 53 countries.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Ratio estimators' for particular source types:
Journal articles Dissertations / Theses Books
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography