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Journal articles on the topic 'COEFFICIENT ESTIMATES'

Author: Grafiati

Published: 11 September 2023

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1

Lentz, S. J., K. A. Davis, J. H. Churchill, and T. M. DeCarlo. "Coral Reef Drag Coefficients – Water Depth Dependence." Journal of Physical Oceanography 47, no. 5 (May 2017): 1061–75. http://dx.doi.org/10.1175/jpo-d-16-0248.1.

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AbstractA major challenge in modeling the circulation over coral reefs is uncertainty in the drag coefficient because existing estimates span two orders of magnitude. Current and pressure measurements from five coral reefs are used to estimate drag coefficients based on depth-average flow, assuming a balance between the cross-reef pressure gradient and the bottom stress. At two sites wind stress is a significant term in the cross-reef momentum balance and is included in estimating the drag coefficient. For the five coral reef sites and a previous laboratory study, estimated drag coefficients increase as the water depth decreases consistent with open channel flow theory. For example, for a typical coral reef hydrodynamic roughness of 5 cm, observational estimates, and the theory indicate that the drag coefficient decreases from 0.4 in 20 cm of water to 0.005 in 10 m of water. Synthesis of results from the new field observations with estimates from previous field and laboratory studies indicate that coral reef drag coefficients range from 0.2 to 0.005 and hydrodynamic roughnesses generally range from 2 to 8 cm. While coral reef drag coefficients depend on factors such as physical roughness and surface waves, a substantial fraction of the scatter in estimates of coral reef drag coefficients is due to variations in water depth.

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2

Zaprawa, Paweł, and Katarzyna Tra̧bka-Wiȩcław. "Estimates of Coefficient Functionals for Functions Convex in the Imaginary-Axis Direction." Symmetry 12, no. 10 (October 20, 2020): 1736. http://dx.doi.org/10.3390/sym12101736.

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Let C0(h) be a subclass of analytic and close-to-convex functions defined in the open unit disk by the formula Re{(1−z2)f′(z)}>0. In this paper, some coefficient problems for C0(h) are considered. Some properties and bounds of several coefficient functionals for functions belonging to this class are provided. The main aim of this paper is to find estimates of the difference and of sum of successive coefficients, bounds of the sum of the first n coefficients and bounds of the n-th coefficient. The obtained results are used to determine coefficient estimates for both functions convex in the imaginary-axis direction with real coefficients and typically real functions. Moreover, the sum of the first initial coefficients for functions with a positive real part and with a fixed second coefficient is estimated.

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3

Darus, Maslina, and Ajab Akbarally. "Coefficient estimates for Ruscheweyh derivatives." International Journal of Mathematics and Mathematical Sciences 2004, no. 36 (2004): 1937–42. http://dx.doi.org/10.1155/s0161171204309051.

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We consider functionsf, analytic in the unit disc and of the normalized formf(z)=z+∑n=2∞anzn. For functionsf∈R¯δ(β), the class of functions involving the Ruscheweyh derivatives operator, we give sharp upper bounds for the Fekete-Szegö functional|a3−μa22|.

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4

Idrisa, Hamimu, S. A. Kadam, and S. D. Gorantiwar. "Estimation of Crop Coefficients Based on Normalize Difference Vegetation Index." Journal of Agriculture Research and Technology 47, no. 03 (2022): 381–88. http://dx.doi.org/10.56228/jart.2022.47320.

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Crop coefficient is one of the most important parameters used for the estimation of crop evapotranspiration (ETc). Crop coefficient (Kc)-based estimation of crop evapotranspiration is most commonly used methods for irrigation water management. However, crop coefficient approach used for estimation ETc using the generalized crop coefficients mentioned in Irrigation and Drainage Paper No. 56 of the Food and Agricultural Organization of the United Nations can contribute to crop evapotranspiration estimates that are substantially different from actual crop evapotranspiration. The colinear relationship between the crop coefficient curve and a satellitederived Normalized Difference Vegetation Index (NDVI) showed potential for modeling a crop coefficient as a function of the NDVI, which is also one among the methods used for estimation of ETc in irrigation water management. The present study was conducted with objectives to present the techniques and procedures to develop and estimates Kc based on vegetation index (NDVI) extracted from satellite data. The relationships between and NDVI and crop coefficients (Kc) of wheat and chickpea for corresponding months were developed. The regression models developed are: (Kc) NDVI = 6.3268*NDVI-1.4207 for wheat and (Kc) NDVI = 5.7866 * NDVI-1.6699 for chickpea. The models showed strong relationships with R2= 0.86 and R2=0.84 for wheat and chickpea, respectively. The model and techniques to develop and estimate crop coefficients can be used in other regions in the global, and hence estimate crop evapotranspiration. The crop coefficients (Kc) estimated based on NDVI are useful for irrigation scheduling, evaluating irrigation performance, irrigation water management, and estimation of water use efficiency.

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Zaprawa, Paweł, Anna Futa, and Magdalena Jastrzębska. "On Coefficient Functionals for Functions with Coefficients Bounded by 1." Mathematics 8, no. 4 (April 1, 2020): 491. http://dx.doi.org/10.3390/math8040491.

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In this paper, we discuss two well-known coefficient functionals a 2 a 4 - a 3 2 and a 4 - a 2 a 3 . The first one is called the Hankel determinant of order 2. The second one is a special case of Zalcman functional. We consider them for functions in the class Q R ( 1 2 ) of analytic functions with real coefficients which satisfy the condition ( ) f ( z ) z > 1 2 for z in the unit disk Δ . It is known that all coefficients of f ∈ Q R ( 1 2 ) are bounded by 1. We find the upper bound of a 2 a 4 - a 3 2 and the bound of | a 4 - a 2 a 3 | . We also consider a few subclasses of Q R ( 1 2 ) and we estimate the above mentioned functionals. In our research two different methods are applied. The first method connects the coefficients of a function in a given class with coefficients of a corresponding Schwarz function or a function with positive real part. The second method is based on the theorem of formulated by Szapiel. According to this theorem, we can point out the extremal functions in this problem, that is, functions for which equalities in the estimates hold. The obtained estimates significantly extend the results previously established for the discussed classes. They allow to compare the behavior of the coefficient functionals considered in the case of real coefficients and arbitrary coefficients.

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6

Raghunathan, Trivellore E., Paula K. Diehr, and Allen D. Cheadle. "Combining Aggregate and Individual Level Data to Estimate an Individual Level Correlation Coefficient." Journal of Educational and Behavioral Statistics 28, no. 1 (March 2003): 1–19. http://dx.doi.org/10.3102/10769986028001001.

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Methods are developed that use aggregate data, possibly based on a large number of individuals, and individual level data, from a small fraction of individuals from the same or similar population, to eliminate ecological bias inherent in the analysis of aggregate data. The primary focus is on estimating the individual level correlation coefficient but the proposed methodology can be extended to estimate regression coefficients. Two approaches, the method of moments and the maximum likelihood, are developed for a bivariate distribution, but can be extended to a multivariate distribution. The method of moments develops a corrected estimate of the within-group covariance matrix, which is then used to estimate the individual level correlation and regression coefficients. The second method assumes bivariate normality and maximizes the combined likelihood function based on the two data sets. The maximum likelihood estimates are obtained using the EM-algorithm. A simulation study investigates the repeated sampling properties of these procedures in terms of bias and the mean square error of the point estimates and the actual coverage of the confidence intervals. The maximum likelihood estimates are almost unbiased and the confidence intervals are well calibrated for simulation conditions considered. The method of moments estimates have the same desirable properties for some simulation conditions. Under all conditions, the correlation coefficient between aggregate variables is severely biased as an estimate of the individual level correlation coefficient.

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7

Orhan, Halit, Nihat Yagmur, and Murat Caglar. "Coefficient estimates for Sakaguchi type functions." SARAJEVO JOURNAL OF MATHEMATICS 8, no. 2 (November 2012): 235–44. http://dx.doi.org/10.5644/sjm.08.2.05.

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8

SAKAR, F. Müge, and H. Özlem GÜNEY. "Coefficient estimates for bi-concave functions." Communications Faculty Of Science University of Ankara Series A1Mathematics and Statistics 68, no. 1 (April 11, 2018): 53–60. http://dx.doi.org/10.31801/cfsuasmas.443600.

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9

Ozawa, Mitsuru. "Coefficient estimates for the class $\Sigma$." Kodai Mathematical Journal 9, no. 1 (1986): 123–33. http://dx.doi.org/10.2996/kmj/1138037155.

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10

Totik, Vilmos. "Coefficient estimates on general compact sets." Publicationes Mathematicae Debrecen 96, no. 1-2 (January 1, 2020): 131–39. http://dx.doi.org/10.5486/pmd.2020.8631.

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11

McCarthy, John E. "Coefficient estimates on weighted Bergman spaces." Duke Mathematical Journal 76, no. 3 (December 1994): 751–60. http://dx.doi.org/10.1215/s0012-7094-94-07630-8.

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12

Saritha, G. P., and S. Latha. "Coefficient Estimates for SAKAGUCHI Type Functions." International Journal of Mathematics Trends and Technology 11, no. 1 (July 25, 2014): 10–23. http://dx.doi.org/10.14445/22315373/ijmtt-v11p502.

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13

Chiew, FHS, and TA Mcmahon. "Assessing the adequacy of catchment streamflow yield estimates." Soil Research 31, no. 5 (1993): 665. http://dx.doi.org/10.1071/sr9930665.

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Rainfall-runoff models are frequently used by hydrologists to estimate runoff from rainfall and climate data, with the model adequacy assessed by comparing the level of agreement between flows simulated by the model and the recorded flows. This paper describes simple methods (visual plots, statistical parameters and dimensionless coefficients) which are commonly used to compare estimated and recorded streamflow time series and discusses their advantages and limitations. Results of a survey conducted to ascertain the required quality of flow estimates before they are considered to be satisfactory, as well as to identify preferred methods used by hydrologists in Australia to determine the adequacy of streamflow estimates, are also discussed in this paper. Information from the survey is also used to suggest objective criteria based on dimensionless coefficients that can be used as guides in assessing the adequacy of flows estimated by rainfall-runoff models. In particular, the coefficient of efficiency is a very useful indicator in assessing model adequacy.

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14

Raza, M., D. K. Thomas, and A. Riaz. "Coefficient estimates for starlike and convex functions related to sigmoid functions." Ukrains’kyi Matematychnyi Zhurnal 75, no. 5 (May 24, 2023): 683–97. http://dx.doi.org/10.37863/umzh.v75i5.7093.

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UDC 517.5 We give sharp coefficient bounds for starlike and convex functions related to modified sigmoid functions. We also provide some sharp coefficients bounds for the inverse functions and sharp bounds for the initial logarithmic coefficients and some coefficient differences.

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15

ALI, MD FIROZ, and A. VASUDEVARAO. "Coefficient estimates of negative powers and inverse coefficients for certain starlike functions." Proceedings - Mathematical Sciences 127, no. 3 (February 13, 2017): 449–62. http://dx.doi.org/10.1007/s12044-017-0328-5.

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16

Răducanu, Dorina. "Coefficient Estimates for a Subclass of Starlike Functions." Mathematics 8, no. 10 (September 24, 2020): 1646. http://dx.doi.org/10.3390/math8101646.

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In this note, we consider a subclass H3/2(p) of starlike functions f with f″(0)=p for a prescribed p∈[0,2]. Usually, in the study of univalent functions, estimates on the Taylor coefficients, Fekete–Szegö functional or Hankel determinats are given. Another coefficient problem which has attracted considerable attention is to estimate the moduli of successive coefficients |an+1|−|an|. Recently, the related functional |an+1−an| for the initial successive coefficients has been investigated for several classes of univalent functions. We continue this study and for functions f(z)=z+∑n=2∞anzn∈H3/2(p), we investigate upper bounds of initial coefficients and the difference of moduli of successive coefficients |a3−a2| and |a4−a3|. Estimates of the functionals |a2a4−a32| and |a4−a2a3| are also derived. The obtained results expand the scope of the theoretical results related with the functional |an+1−an| for various subclasses of univalent functions.

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17

Anand, Swati, Naveen Kumar Jain, and Sushil Kumar. "Certain Estimates of Normalized Analytic Functions." Mathematica Slovaca 72, no. 1 (February 1, 2022): 85–102. http://dx.doi.org/10.1515/ms-2022-0006.

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Abstract Let ϕ be a normalized convex function defined on open unit disk D . For a unified class of normalized analytic functions which satisfy the second order differential subordination f′(z) + αzf″(z) ≺ ϕ(z) for all z ∈ D , we investigate the distortion theorem and growth theorem. Further, the bounds on initial logarithmic coefficients, inverse coefficient and the second Hankel determinant involving the inverse coefficients are examined.

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18

Green, Edwin J., and William E. Strawderman. "Stein-rule estimation of coefficients for 18 eastern hardwood cubic volume equations." Canadian Journal of Forest Research 16, no. 2 (April 1, 1986): 249–55. http://dx.doi.org/10.1139/x86-044.

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A Stein-rule estimator, which shrinks least squares estimates of regression parameters toward their weighted average, was employed to estimate the coefficient in the constant form factor volume equation for 18 species simultaneously. The Stein-rule procedure was applied to ordinary least squares estimates and weighted least squares estimates. Simulation tests on independent validation data sets revealed that the Stein-rule estimates were biased, but predicted better than the corresponding least squares estimates. The Stein-rule procedures also yielded lower estimated mean square errors for the volume equation coefficient than the corresponding least squares procedure. Different methods of withdrawing sample data from the total sample available for each species revealed that the superiority of Stein-rule procedures over least squares decreased as the sample size increased and that the Stein-rule procedures were robust to unequal sample sizes, at least on the scale studied here.

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19

Ravichandran, V., and Shelly Verma. "Estimates for coefficients of certain analytic functions." Filomat 31, no. 11 (2017): 3539–52. http://dx.doi.org/10.2298/fil1711539r.

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For -1 ? B ? 1 and A > B, let S*[A,B] denote the class of generalized Janowski starlike functions consisting of all normalized analytic functions f defined by the subordination z f'(z)/f(z)< (1+Az)/(1+Bz) (?z?<1). For -1 ? B ? 1 < A, we investigate the inverse coefficient problem for functions in the class S*[A,B] and its meromorphic counter part. Also, for -1 ? B ? 1 < A, the sharp bounds for first five coefficients for inverse functions of generalized Janowski convex functions are determined. A simple and precise proof for inverse coefficient estimations for generalized Janowski convex functions is provided for the case A = 2?-1(?>1) and B = 1. As an application, for F:= f-1, A = 2?-1 (?>1) and B = 1, the sharp coefficient bounds of F/F' are obtained when f is a generalized Janowski starlike or generalized Janowski convex function. Further, we provide the sharp coefficient estimates for inverse functions of normalized analytic functions f satisfying f'(z)< (1+z)/(1+Bz) (?z? < 1, -1 ? B < 1).

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20

Dahl, Christopher, Brent Harding, and Harry Wiant. "Quick Volume Coefficient Determination for Point Sampling." Northern Journal of Applied Forestry 24, no. 4 (December 1, 2007): 314–16. http://dx.doi.org/10.1093/njaf/24.4.314.

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Abstract Grosenbaugh developed a formula for making quick point-sample estimates of sawtimber volume without measuring diameter. Local coefficients were created for a study area in central Pennsylvania hardwoods and were compared with volume estimates using a range of previously published coefficients. Results indicate that a general constant coefficient of 66 produces sawtimber volume estimates that are as good as using species-specific local coefficients for Pennsylvania hardwoods.

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21

Prokhorov, D. "Even coefficient estimates for bounded univalent functions." Annales Polonici Mathematici 58, no. 3 (1993): 267–73. http://dx.doi.org/10.4064/ap-58-3-267-273.

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22

Viana, Marios A. G. "Combined Bayesian estimates for the equicorrelation coefficient." Canadian Journal of Statistics 23, no. 1 (March 1995): 43–53. http://dx.doi.org/10.2307/3315550.

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23

Ularu, N. "Coefficient Estimates for Bi-Univalent Bazilevic Functions." Analysis in Theory and Applications 30, no. 3 (June 2014): 275–80. http://dx.doi.org/10.4208/ata.2014.v30.n3.3.

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24

Kamble, P. N., and M. G. Shrigan. "INITIAL COEFFICIENT ESTIMATES FOR BI-UNIVALENT FUNCTIONS." Far East Journal of Mathematical Sciences (FJMS) 105, no. 2 (July 16, 2018): 271–82. http://dx.doi.org/10.17654/ms105020271.

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25

Jackson, John E. "Estimation of Models with Variable Coefficients." Political Analysis 3 (1991): 27–49. http://dx.doi.org/10.1093/pan/3.1.27.

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The ordinary least squares (OLS) estimator gives biased coefficient estimates if coefficients are not constant for all cases but vary systematically with the explanatory variables. This article discusses several different ways to estimate models with systematically and randomly varying coefficients using estimated generalized least squares and maximum likelihood procedures. A Monte Carlo simulation of the different methods is presented to illustrate their use and to contrast their results to the biased results obtained with ordinary least squares. Several applications of the methods are discussed and one is presented in detail. The conclusion is that, in situations with variables coefficients, these methods offer relatively easy means for overcoming the problems.

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26

Consiglieri, Luisa. "Explicit Estimates for Solutions of Mixed Elliptic Problems." International Journal of Partial Differential Equations 2014 (March 31, 2014): 1–16. http://dx.doi.org/10.1155/2014/845760.

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We deal with the existence of quantitative estimates for solutions of mixed problems to an elliptic second-order equation in divergence form with discontinuous coefficients. Our concern is to estimate the solutions with explicit constants, for domains in ℝn (n≥2) of class C0,1. The existence of L∞ and W1,q estimates is assured for q=2 and any q<n/(n-1) (depending on the data), whenever the coefficient is only measurable and bounded. The proof method of the quantitative L∞ estimates is based on the De Giorgi technique developed by Stampacchia. By using the potential theory, we derive W1,p estimates for different ranges of the exponent p depending on the fact that the coefficient is either Dini-continuous or only measurable and bounded. In this process, we establish new existences of Green functions on such domains. The last but not least concern is to unify (whenever possible) the proofs of the estimates to the extreme Dirichlet and Neumann cases of the mixed problem.

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27

Castiglioni, P., G. Mancia, G. Parati, A. Pedotti, and M. Di Rienzo. "Critical Appraisal of Indices for the Assessment of Baroreflex Sensitivity." Methods of Information in Medicine 36, no. 04/05 (October 1997): 246–49. http://dx.doi.org/10.1055/s-0038-1636857.

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Abstract:The sequence technique and the spectral estimation of the alpha coefficient are currently employed for the assessment of “spontaneous” baroreflex sensitivity (BRS). The comparison of performance and effectiveness of these techniques is obtained by the analysis of systolic blood pressure (SBP) and pulse interval (PI) tracings recorded in conscious cats before and after baroreceptor denervation. Results indicate that (1) the average BRS estimates obtained by the sequence technique and by the alpha coefficient at the respiratory frequency are similar, (2) the alpha coefficients computed at the respiratory frequency tend to be higher than alpha coefficients estimated at 0.1 Hz, and (3) in spite of what is traditionally claimed, the PI-SBP coherence does not seem to represent a reliable parameter to enhance the specificity of the spectral estimate, because coherence values often remain above the 0.5 threshold also after baroreceptor denervation.

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28

Ali, Md Firoz, and Allu Vasudevarao. "Coefficient estimates and integral mean estimates for certain classes of analytic functions." Comptes Rendus Mathematique 357, no. 5 (May 2019): 436–42. http://dx.doi.org/10.1016/j.crma.2019.04.013.

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29

Mishra, A. K., and S. Barik. "Estimation of initial coefficients of certain λ-bi-starlike analytic functions." Asian-European Journal of Mathematics 09, no. 03 (August 2, 2016): 1650066. http://dx.doi.org/10.1142/s1793557116500662.

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For the class of [Formula: see text]-bi-starlike functions defined in the unit disc, we find bounds on the modulii of the first three Taylor–Maclaurin’s coefficients. Our estimate on the second and the third coefficients improve upon previously known bounds. The result on the fourth coefficient is new. Similarly, for the [Formula: see text]-bi-starlike functions defined in the exterior of the unit disc, we find estimates on the first three coefficients. Our findings on the zeroth and the first coefficients extend results known earlier. The results are consummated by refining the first coefficient of a corresponding Carathéodory functions.

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30

Fguiri, Ali, Naouel Daouas, M.-Sassi Radhouani, and Habib Ben Aissia. "Inverse analysis for the determination of heat transfer coefficient." Canadian Journal of Physics 91, no. 12 (December 2013): 1034–43. http://dx.doi.org/10.1139/cjp-2012-0520.

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The parallel hot wire technique is considered an effective and accurate means of experimental measurement of thermal conductivity. However, the assumptions of infinite medium and ideal infinitely thin and long heat source lead to some restrictions in the applicability of this technique. To make an effective experiment design, a numerical analysis should be carried out a priori, which requires a precise specification of the heating source strength and the heat transfer coefficient on the external surface. In this work, a more accurate physical and mathematical modeling of an experimental setup based on the parallel hot wire method is considered to estimate the two above-mentioned parameters from noisy temperature histories measured inside the material. Based on a sensitivity analysis, the heating source strength is estimated first using early time measurements. With such estimated value, determination of the heat transfer coefficient using temperatures measured at later times is then considered. The Levenberg–Marquardt (LM) method is successfully applied using a single experiment for the inverse solution of the two present parameter estimation problems. Estimates of this gradient-based deterministic method are validated with a stochastic method (Kalman filter). The effects of the measurement location, the heating duration, the measurement time step, and the LM parameter on the estimates and their associated confidence bounds are investigated. Used in the traditional fitting procedure of the parallel hot wire technique, the estimated heating source power provides a reasonable agreement between fitted and exact values of the thermal conductivity and the thermal diffusivity.

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31

Rainey, Carlisle. "Transformation-Induced Bias: Unbiased Coefficients Do Not Imply Unbiased Quantities of Interest." Political Analysis 25, no. 3 (July 2017): 402–9. http://dx.doi.org/10.1017/pan.2017.11.

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Political scientists commonly focus on quantities of interest computed from model coefficients rather than on the coefficients themselves. However, the quantities of interest, such as predicted probabilities, first differences, and marginal effects, do not necessarily inherit the small-sample properties of the coefficient estimates. Indeed, unbiased coefficient estimates are neither necessary nor sufficient for unbiased estimates of the quantities of interest. I characterize this transformation-induced bias, calculate an approximation, illustrate its importance with two simulation studies, and discuss its relevance to methodological research.

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32

Andersson, Björn, and Tao Xin. "Large Sample Confidence Intervals for Item Response Theory Reliability Coefficients." Educational and Psychological Measurement 78, no. 1 (June 22, 2017): 32–45. http://dx.doi.org/10.1177/0013164417713570.

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In applications of item response theory (IRT), an estimate of the reliability of the ability estimates or sum scores is often reported. However, analytical expressions for the standard errors of the estimators of the reliability coefficients are not available in the literature and therefore the variability associated with the estimated reliability is typically not reported. In this study, the asymptotic variances of the IRT marginal and test reliability coefficient estimators are derived for dichotomous and polytomous IRT models assuming an underlying asymptotically normally distributed item parameter estimator. The results are used to construct confidence intervals for the reliability coefficients. Simulations are presented which show that the confidence intervals for the test reliability coefficient have good coverage properties in finite samples under a variety of settings with the generalized partial credit model and the three-parameter logistic model. Meanwhile, it is shown that the estimator of the marginal reliability coefficient has finite sample bias resulting in confidence intervals that do not attain the nominal level for small sample sizes but that the bias tends to zero as the sample size increases.

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33

Podvezko, Valentinas. "AGREEMENT OF EXPERT ESTIMATES." Technological and Economic Development of Economy 11, no. 2 (June 30, 2005): 101–7. http://dx.doi.org/10.3846/13928619.2005.9637688.

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The application of multicriteria methods largely depends on the calculation of the criteria weights based on expert evaluation. The results obtained can be used for practical purposes if expert judgments are in good agreement. This may be determined by the concordance of a coefficient obtained by ranking the available alternatives. The paper considers a possibility to apply the concordance coefficient in cases when expert evaluation is not based on ranking. The calculations reveal the dependence of the agreement of expert estimates on a particular method used. The highest degree of agreement has been obtained by using the direct ranking method. The effect of equally assessed criteria, i. e. the tied ranks on the concordance coefficient and thereby on the level of expert judgments agreement is usually insignificant and cannot change the results of rating.

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34

Taylor, Marshall A. "Visualization strategies for regression estimates with randomization inference." Stata Journal: Promoting communications on statistics and Stata 20, no. 2 (June 2020): 309–35. http://dx.doi.org/10.1177/1536867x20930999.

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Coefficient plots are a popular tool for visualizing regression estimates. The appeal of these plots is that they visualize confidence intervals around the estimates and generally center the plot around zero, meaning that any estimate that crosses zero is statistically nonsignificant at least at the alpha level around which the confidence intervals are constructed. For models with statistical significance levels determined via randomization models of inference and for which there is no standard error or confidence intervals for the estimate itself, these plots appear less useful. In this article, I illustrate a variant of the coefficient plot for regression models with p-values constructed using permutation tests. These visualizations plot each estimate’s p-value and its associated confidence interval in relation to a specified alpha level. These plots can help the analyst interpret and report the statistical and substantive significances of their models. I illustrate using a nonprobability sample of activists and participants at a 1962 anticommunism school.

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35

Bennett, Darin C., and Leslie E. Hart. "Metabolizable energy of fish when fed to captive Great Blue Herons (Ardea herodias)." Canadian Journal of Zoology 71, no. 9 (September 1, 1993): 1767–71. http://dx.doi.org/10.1139/z93-251.

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The efficiency with which the gross energy content of herring (Clupea harengus), mackerel (Scomber scombrus), and trout (Oncorhynchus mykiss) is metabolized was determined for 11 captive Great Blue Herons (Ardea herodias). There was a linear relationship between apparent metabolized energy and gross energy intake for the mackerel and trout. This relationship was lower and more variable for herring. Estimates of the apparent metabolizable energy coefficient for mackerel and trout were affected by the level of energy intake. Correcting for endogenous energy losses in the excreta yielded estimates of true metabolizable energy coefficients that were independent of gross energy intake. The true metabolizable energy coefficient of mackerel and trout did not differ and averaged 0.866 (SD = 0.014, n = 3 diets). Correcting for nitrogen retention did not improve the estimate of the metabolizable energy coefficient. The metabolizable energy coefficient of herring was highly variable and showed no consistent pattern in relation to energy intake.

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36

Lindquist, John L., David A. Mortensen, Sharon A. Clay, Richard Schmenk, James J. Kells, Kirk Howatt, and Philip Westra. "Stability of Corn (Zea mays)-Velvetleaf (Abutilon theophrasti) Interference Relationships." Weed Science 44, no. 2 (June 1996): 309–13. http://dx.doi.org/10.1017/s0043174500093930.

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The crop-weed interference relationship is a critical component of bioeconomic weed management models. Multi-year field experiments were conducted at five locations to determine the stability of corn-velvetleaf interference relationships across years and locations. Two coefficients (I and A) of a hyperbolic equation were estimated for each data set using nonlinear regression procedures. The I and A coefficients represent percent corn yield loss as velvetleaf density approaches zero, and maximum percent corn yield loss, respectively. The coefficient I was stable across years at two locations, but varied across years at one location. The coefficient A did not vary across years within locations. Both coefficients, however, varied among locations. Results do not support the use of common coefficient estimates for all locations within a region.

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Bulut, Serap. "Coefficient estimates for Libera type bi-close-to-convex functions." Mathematica Slovaca 71, no. 6 (December 1, 2021): 1401–10. http://dx.doi.org/10.1515/ms-2021-0060.

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Abstract In a very recent paper, Wang and Bulut [A note on the coefficient estimates of bi-close-to-convex functions, C. R. Acad. Sci. Paris, Ser. I 355 (2017), 876–880] determined the estimates for the general Taylor-Maclaurin coefficients of functions belonging to the bi-close-to-convex function class. In this study, we introduce the class of Libera type bi-close-to-convex functions and obtain the upper bounds for the coefficients of functions belonging to this class. Our results generalize the results in the above mentioned paper.

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Răducanu, Dorina. "On Coefficient Estimates for a Certain Class of Analytic Functions." Mathematics 11, no. 1 (December 20, 2022): 12. http://dx.doi.org/10.3390/math11010012.

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In this paper, we consider a subclass SQ of normalized analytic functions f satisfying ℜf′(z)>1/2. For the functions in the class SQ, we determine upper bounds for a number of coefficient estimates, among which are initial coefficients, the second Hankel determinant, and the Zalcman functional. Upper estimates for higher-order Schwarzian derivatives are also obtained.

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39

Imron, Imron, Dadan Sunandar, Rommy Suprapto, and Nunuk Listyowati. "THE APPLICATION OF RAPD FINGERPRINTING TO ASSESS INBREEDING LEVELS IN THE CULTURED POPULATIONS OF GIANT FRESHWATER PRAWN, Macrobrachium rosenbergii." Indonesian Aquaculture Journal 5, no. 1 (June 30, 2010): 73. http://dx.doi.org/10.15578/iaj.5.1.2010.73-82.

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Inbreeding has been one of central issues with regard to genetic quality of aquaculture species, including giant fresh water prawn (GFP). Conventional methods for the estimation of inbreeding level are available, such as pedigree analyses which requires a good pedigree record which, unfortunately, is rarely available. Likewise, microsatellite molecular markers commonly applied to obtain the coefficient inbreeding estimates are both laborious and expensive. Hence, an alternative method of inbreeding assessment which is relatively easy but reliable is in need. This study was aimed to explore the applicability of RAPD fingerprinting, which is known to be simple and affordable, to estimate inbreeding level of GFP population. Three GFP populations namely inbred, outbred, and farm populations with inbreeding level of 25%, 0%, and unknown, respectively, were genotyped using five polymorphic RAPD primers. The inbreeding levels mentioned within the first two populations were determined using pedigree analysis. RAPD banding patterns were then used to calculate band sharing index (BSI) and inbreeding coefficient (F). Assessment of the applicability of inbreeding level estimates obtained by RAPD markers was performed by comparing them to those estimated by pedigree analysis. Results show that RAPD fingerprinting was capable of delineating populations differing in their inbreeding coefficients. The pattern resulted from molecular inbreeding coefficient within the inbred and outbred groups, was congruent with that shown by pedigree analysis, while the farm population showed closeness to the inbred group. While the accuracy of the estimate needs to be verified further, this study suggests that RAPD fingerprinting is applicable to estimate population inbreeding level, particularly due to its technical simplicity and cost affordability.

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Zaprawa, Paweł. "Estimates of Initial Coefficients for Bi-Univalent Functions." Abstract and Applied Analysis 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/357480.

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We consider the Fekete-Szegö inequalities for classes which were defined by Murugusundaramoorthy et al. (2013). These inequalities will result in bounds of the third coefficient which are better than these obtained by Murugusundaramoorthy et al. (2013). Moreover, we discuss two other classes of bi-univalent functions. The estimates of initial coefficients in these classes are obtained.

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Leung, Y. J., and G. Schober. "Low order coefficient estimates in the class \sigma." Annales Academiae Scientiarum Fennicae Series A I Mathematica 11 (1986): 39–61. http://dx.doi.org/10.5186/aasfm.1986.1111.

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Darwish, Hanan, Suliman Sowileh, and Abd AL-Monem Lashin. "Coefficient Estimates of some Classes of Rational Functions." Open Journal of Mathematical Analysis 2(2018), no. 2 (December 31, 2018): 114–28. http://dx.doi.org/10.30538/psrp-oma2018.0022.

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43

Konakazawa, Seiji. "Remarks on geometric properties of certain coefficient estimates." Kodai Mathematical Journal 10, no. 2 (1987): 242–49. http://dx.doi.org/10.2996/kmj/1138037419.

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44

Viana, Marlos A. G. "Combined Maximum Likelihood Estimates for the Equicorrelation Coefficient." Biometrics 50, no. 3 (September 1994): 813. http://dx.doi.org/10.2307/2532793.

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Juneja, O. P., and S. Rajasekaran. "Coefficient estimates for inverses of α-spiral functions." Complex Variables, Theory and Application: An International Journal 6, no. 2-4 (October 1986): 99–108. http://dx.doi.org/10.1080/17476938608814162.

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46

Menke, Klaus. "Coefficient estimates for functions univalent in an annulus." Complex Variables, Theory and Application: An International Journal 19, no. 1-2 (July 1992): 91–96. http://dx.doi.org/10.1080/17476939208814562.

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Alimohammadi, Davood, Nak Eun Cho, Ebrahim Analouei Adegani, and Ahmad Motamednezhad. "Argument and Coefficient Estimates for Certain Analytic Functions." Mathematics 8, no. 1 (January 5, 2020): 88. http://dx.doi.org/10.3390/math8010088.

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The aim of the present paper is to introduce a new class G α , δ of analytic functions in the open unit disk and to study some properties associated with strong starlikeness and close-to-convexity for the class G α , δ . We also consider sharp bounds of logarithmic coefficients and Fekete-Szegö functionals belonging to the class G α , δ . Moreover, we provide some topics related to the results reported here that are relevant to outcomes presented in earlier research.

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Mason, Corinne, Reynald Allam, and Michael T. Brannick. "How to Meta-Analyze Coefficient-of-Stability Estimates." Educational and Psychological Measurement 67, no. 5 (June 6, 2007): 765–83. http://dx.doi.org/10.1177/0013164407301532.

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Giellis, George R., and T. C. Yang. "Sea ice reflection coefficient estimates at low frequency." Journal of the Acoustical Society of America 82, S1 (November 1987): S31. http://dx.doi.org/10.1121/1.2024755.

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Tandler, Talia, Emma Gellman, Dayna De La Cruz, and David J. Ellerby. "Drag coefficient estimates from coasting bluegill sunfishLepomis macrochirus." Journal of Fish Biology 94, no. 3 (February 13, 2019): 532–34. http://dx.doi.org/10.1111/jfb.13906.

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