Assumed similarity and opinion certainty.

To examine the effect of projected attitude similarity on certainty of own attitude, 2 samples of male undergraduates (N?=?40), commuters and fraternity members, indicated their own attitudinal position on 8 issues and then served in 1 of 4 opinion projection conditions: estimating the positions of those in their in-group, a student out-group, an irrelevant out-group (old veterans), or a no-target group. They then indicated their certainty about their previously expressed positions. In both studies, in-group targets elicited the most assumed similarity, and the irrelevant out-group elicited the least. Certainty of S's own position was greater after estimation of the positions of in-group Ss than after estimation of the opinions of relevant or irrelevant out-group Ss, or when given no opportunity to project. These certainty effects were due primarily to those issues Ss considered important. Additional analyses provided empirical support for 2 orthogonal components of assumed similarity, item content similarity and elevation similarity. The importance of a strong group identity as a basis for the increment in certainty conferred by assumed in-group similarity is discussed. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Physiological alcohol dependence symptoms in early adulthood: A longitudinal perspective.

The developmental course of physiological dependence on alcohol was investigated by estimating the prevalance, stability, and prognostic significance of individual tolerance and withdrawal symptoms, prospectively over 7 years, in 450 young adults. Different prevalence rates and patterns of stability were observed with alternate tolerance items. Consistently low base rates were observed for all withdrawal items. Person-level stability of tolerance and withdrawal indicators was moderate at test-retest intervals of 1 year and increasingly modest at longer intervals. Reporting tolerance and withdrawal in early adulthood was associated with a substantial risk for later alcohol use disorder. Results suggest that the likelihood of experiencing tolerance or withdrawal symptoms may vary as a function of an individual's stage of development and drinking history. Implications for future assessment and classification of alcohol dependence are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison of methods for analyzing binary data arising from two-sample twin studies

The study of twins is widely used for research into genetic and environmental influences on human outcome measurements. For the study design in which independent samples of monozygotic and dizygotic twins are compared with respect to their similarity on a binary trait, several statistical methods have been proposed. Using a Monte Carlo simulation, we compare the five following procedures: 1) goodness-of-fit method based on the common correlation model, 2) normal approximation of the maximum likelihood estimators of the common correlation coefficients, 3) Ramakrishnan et al. [(1992) Genet Epidemiol 9:273-282] method of odds ratio comparison, 4) generalized estimating equations method of odds ratio estimation, and 5) tetrachoric correlation method. The results show that the goodness-of-fit approach has similar or better performance in both type-one error rates and power than the other methods in all parameter settings. Its advantage with respect to type-one error rates is particularly clear under conditions of small sample sizes, extreme prevalences, or high values of the intraclass correlation coefficients. Therefore, the goodness-of-fit method is recommended for the two-sample twin study design.     

典型离子化合物标准熵的估算模型

 提出了用于估算典型离子化合物标准熵的双参数模型。此模型可以用来估算由碱金属、碱土金属与氧族元素和卤族元素组成的离子化合物的标准熵。模型通过回归求解给出了估算时各元素的估算参数值。由此模型估算离子化合物的标准熵时,平均误差为2.473J·mol-1·K-1,标准差为3.274 J·mol-1·K-1。模型估算误差符合正态分布,并且在与离子束缚模型等估算模型比较中显示了较高的精确度,优于现有的其他估算方法。     

Interactional approach to interpersonal attraction.

Believing they were exchanging attitude surveys with a stranger, 270 undergraduates of high or low self-esteem (Texas Social Behavior Inventory) were randomly assigned to 0, 50, or 100% attitude similarity conditions. They indicated on the Interpersonal Judgment Scale their attraction to the stranger and estimates of the stranger's probable attraction to them. Attitude similarity significantly affected Ss' attraction to the stranger and estimates of strangers' attraction to the S. Ss closely approximated predictions of D. Byrne and D. Nelson's (1965) formula in estimating attraction from the stranger. Moreover, attitude similarity influenced goodness of fit between formula predictions and attraction estimates and influenced assumptions about attraction reciprocity. Self-esteem did not influence attraction to the stranger or expected attraction from the stranger. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Probabilistic Estimating: Mathematics and Applications

In response to the increased risk levels found in today's projects, project participants are attempting to quantify project cost risk. Various detailed and conceptual estimating formats are reviewed and a number of probabilistic estimating methods are introduced. Particular attention is given to the process of matching a suitable probabilistic estimating technique to a specific estimating format. To select an appropriate probabilistic method, an estimator must consider data availability, existing correlations, output data requirements, the form of the, estimating model, and the number of cost elements contained in the model. Existing obstacles to more realistic probabilistic cost estimates are reviewed.     

Prospects for estimating nucleotide divergence with RAPDs

The technique of random amplification of polymorphic DNA (RAPD), which is simply polymerase chain reaction (PCR) amplification of genomic DNA by a single short oligonucleotide primer, produces complex patterns of anonymous polymorphic DNA fragments. The information provided by these banding patterns has proved to be of great utility for mapping and for verification of identity of bacterial strains. Here we consider whether the degree of similarity of the banding patterns can be used to estimate nucleotide diversity and nucleotide divergence. With haploid data, fragments generated by RAPD-PCR can be treated in a fashion very similar to that for restriction-fragment data. Amplification of diploid samples, on the other hand, requires consideration of the fact that presence of a band is dominant to absence of the band. After describing a method for estimating nucleotide divergence on the basis of diploid samples, we summarize the restrictions and criteria that must be met when RAPD data are used for estimating population genetic parameters.     

Development of methods for estimating the <Emphasis Type="Italic">Z</Emphasis> properties of thick rolled products

The main stages of developing the methods for estimating the mechanical properties of rolled plates across the plate thickness (Z properties) and the corresponding standards are described in a chronological manner. The application of experimental fracture mechanics methods for estimating the sensitivity of building steels to laminated fracture is discussed. The effects of the structure dispersity, the steel purity in non-metallic inclusions, and the reduction on the Z properties of rolled products are described.     

Analysis of observational data in speech and language research using generalizability theory

Most research in speech-language pathology relies on observational data collected by human observers or judges. The reliability and generalizability of such measurements are always important considerations. This article reviews classical methods of estimating reliability and proposes that a more powerful approach capable of estimating the dependability of behavioral measurements is available. This approach, based on generalizability theory, provides a practical framework for estimating multiple sources of measurement error in the collection of observational data. Concepts central to generalizability theory are discussed, and a hypothetical data set illustrates the usefulness of generalizability measurements in speech and language research.     

Acute tolerance to spinally administered morphine compares mechanistically with chronically induced morphine tolerance

The mechanistic similarity between acutely and chronically induced morphine tolerance has been previously proposed but remains largely unexplored. Our experiments examined the modulation of acutely induced tolerance to spinally administered morphine by agonists that affect the N-methyl-D-aspartate receptor and nitric oxide synthase systems. Antinociception was detected via the hot water (52.5 degrees C) tail flick test in mice. Intrathecal pretreatment with morphine (40 nmol) produced a 9.6-fold rightward shift in the morphine dose-response curve. This shift confirmed the induction of acute spinal morphine tolerance. Intrathecal copretreatment with the receptor antagonists (competitive and noncompetitive, respectively) dizolcipine (MK801, 3 nmol) or LY235959 (4 pmol) and morphine [40 nmol, intrathecally (i.t.)] attenuated acute tolerance to morphine measured 8 hr later. A 60-min pretreatment of 7-nitroindazole (6 nmol, i.t.), a selective neuronal NOS inhibitor, followed by administration of morphine (40 nmol, i.t.) blocked the induction of morphine tolerance. Intrathecal copretreatment with morphine (40 nmol, i.t.) and agmatine (4 nmol, i.t.), an imidazoline, receptor agonist and putative nitric oxide synthase inhibitor, almost completely abolished acute spinal morphine tolerance. The results of these experiments agree with previous reports using models of chronically induced morphine tolerance. This evidence supports the proposal that the mechanisms responsible for acute morphine tolerance parallel those underlying chronic morphine tolerance. This study attests to the powerful predictive value of acute induction as a model for morphine tolerance.     

Modelling age-specific risk: application to dementia

We give up-to-date methods for estimating the age-specific incidence of a disease and for estimating the effect of risk factors. We recommend taking age as the basic time scale of the analysis; then, the hazard function can be interpreted as the age-specific incidence of the disease. This choice raises a delayed entry problem. We present three methods: the person-years method; the smoothed Nelson-Aalen estimator, and the penalized likelihood approach. When explanatory variables are available, the Poisson model and the Cox model with delayed entry may be used for estimating relative risks; the penalized likelihood approach can also be used. We apply these methods to estimate the age-specific incidence of dementia using data from a large cohort study, Paquid. This 5-year study followed a random initial sample of 3675 subjects with 190 incident cases of dementia. We compare the estimates based on the three possible methods. The estimated incidences computed separately for men and women cross and it is verified that a non-proportional hazards model for gender holds; women below 75 have a lower risk than men while women above 75 have a higher risk.     

Simplified Spreadsheet Solutions.?I: Subcontractor Information System

This paper presents a subcontractor information system (SIS) to support the estimating and project control functions of subcontractors and small∕medium-size contractors. For the proposed SIS to be simple and practical, it was developed in a spreadsheet program designed to maintain information related to resources and projects and to generate important business reports. Resource data are stored in six worksheets for labor, equipment, crews, material, subcontractors, and alternative methods of construction for various tasks. In addition, a separate worksheet is designed for each project to be used for estimating and control purposes. The latter worksheet allows the user to specify the work breakdown structure and optional methods for construction. As such, it represents a transparent estimating model that allows for quick what-if analysis regarding time and cost. In addition, the reporting worksheet provides information related to time, cost, and resource use at the individual and the multiproject levels. In a companion paper, the use of the SIS as basis for overall schedule optimization is described.     

Social sensitivity in the small task-oriented group.

An analysis of variance design is used to investigate the determinants of accuracy in three five-man groups. Analysis is also made of the covariance between accuracy and self-favorability, other-favorability, and similarity of sentiment structure among the Ss. The results show, that estimation of accuracy is a function of (1) characteristics of the estimator, (2) characteristics of the estimatee, (3) the nature of the group and situation, and (4) the particular feelings being estimated. Persons, pairs of persons, and groups whose feelings toward each other are favorable or similar tend to be more accurate in estimating each other's feelings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Settlement of Footing on Compacted Ash Bed

Compacted coal ash fills exhibit capillary stress due to contact moisture and preconsolidation stress due to the compaction process. As such, the conventional methods of estimating settlement of footing on cohesionless soils based on penetration tests become inapplicable in the case of footings on coal ash fills, although coal ash is also a cohesionless material. Therefore, a method of estimating load-settlement behavior of footings resting on coal ash fills accounting for the effect of capillary and preconsolidation stresses is presented here. The proposed method has been validated by conducting plate load tests on laboratory prepared compacted ash beds and comparing the observed and predicted load-settlement behavior. Overestimation of settlement greater than 100% occurs when capillary and preconsolidation stresses are not accounted for, as is the case in conventional methods.     

Positron emission tomography-based boron neutron capture therapy using boronophenylalanine for high-grade gliomas: part II

Based on pharmacokinetic findings of fluorine-18-labeled L-fluoroboronophenylalanine by positron emission tomography (PET), methods for estimating tumor 10B concentration were devised. In clinical practice of boron neutron capture therapy (BNCT) for high-grade gliomas, a large amount of L-boronophenylalanine (L-10B-BPA)-fructose solution is used. Under these conditions, a slow i.v. infusion of L-10B-BPA-fructose solution should be performed for BNCT; therefore, the changes over time in 10B concentration in the target tissue were estimated by convoluting the actual time course of changes in plasma 10B concentration with a PET-based weight function including the proper rate constants [K1 (ml/g/min), k2 (min(-1)), k3 (min(-1)), and k4 (min(-1))]. With this method, the estimated values of 10B concentration in gliomas were very close to the 10B levels in surgical specimens. This demonstrated the similarity in pharmacokinetics between fluorine-18-labeled L-fluoroboronophenylalanine and L-10B-BPA. This method, using the appropriate rate constant, permits the determination of tumor 10B concentration and is widely suitable for clinical BNCT, because the averaged PET data are enough to use in future patients without individual PET study.     

New Methods for Aquifer Parameters from Slug Test Data

An objective method and a diagnostic curve method are developed for estimating the aquifer parameters (storage coefficient and transmissivity) from slug test data on a fully penetrating well. In the objective method, explicit equations are developed for estimating the aquifer parameters. In the diagnostic curve method, a set of unimodal diagnostic curves is developed along with a guiding straight line. The rise or fall in water level of the well is plotted diagnostically on a double logarithmic graph and matched to one of the diagnostic curves plotted on the same scale with a parallel shift of axes, to estimate the aquifer parameters from the dual coordinates of a selected point on the matched portion of the graphs. The unimodal shape of the diagnostic curves and the guiding straight line facilitate the matching and limit the subjectivity. The proposed methods can easily identify a nonideal condition. The estimates of the aquifer parameters obtained using the proposed methods are more accurate than those obtained using the prior curve matching methods. The proposed methods are also able to identify nonideal conditions. It is hoped that the new methods will be of help to field and practicing engineers.     

Inference for odds ratio regression models with sparse dependent data

Suppose the number of 2 x 2 tables is large relative to the average table size, and the observations within a given table are dependent, as occurs in longitudinal or family-based case-control studies. We consider fitting regression models to the odds ratios using table-level covariates. The focus is on methods to obtain valid inferences for the regression parameters beta when the dependence structure is unknown. In this setting, Liang (1985, Biometrika 72, 678-682) has shown that inference based on the noncentral hypergeometric likelihood is sensitive to misspecification of the dependence structure. In contrast, estimating functions based on the Mantel-Haenszel method yield consistent estimators of beta. We show here that, under the estimating function approach, Wald's confidence interval for beta performs well in multiplicative regression models but unfortunately has poor coverage probabilities when an additive regression model is adopted. As an alternative to Wald inference, we present a Mantel-Haenszel quasi-likelihood function based on integrating the Mantel-Haenszel estimating function. A simulation study demonstrates that, in medium-sized samples, the Mantel-Haenszel quasi-likelihood approach yields better inferences than other methods under an additive regression model and inferences comparable to Wald's method under a multiplicative model. We illustrate the use of this quasi-likelihood method in a study of the familial risk of schizophrenia.     

The relationship between sequence and interaction divergence in proteins

There is currently a gap in knowledge between complexes of known three-dimensional structure and those known from other experimental methods such as affinity purifications or the two-hybrid system. This gap can sometimes be bridged by methods that extrapolate interaction information from one complex structure to homologues of the interacting proteins. To do this, it is important to know if and when proteins of the same type (e.g. family, superfamily or fold) interact in the same way. Here, we study interactions of known structure to address this question. We found all instances within the structural classification of proteins database of the same domain pairs interacting in different complexes, and then compared them with a simple measure (interaction RMSD). When plotted against sequence similarity we find that close homologues (30-40% or higher sequence identity) almost invariably interact the same way. Conversely, similarity only in fold (i.e. without additional evidence for a common ancestor) is only rarely associated with a similarity in interaction. The results suggest that there is a twilight zone of sequence similarity where it is not possible to say whether or not domains will interact similarly. We also discuss the rare instances of fold similarities interacting the same way, and those where obviously homologous proteins interact differently.     

Friction Factors for Coniferous Trees along Rivers

A physically based model for estimating the resistance coefficient for coniferous trees in open-channel flow is modified to account for variations in the flexibility between species. The new model is based on the assumption of a linear increase in foliage area with height and a dimensional analysis. It is supported by experiments in air and water. The advantage of the new model over existing methods for estimating resistance factors is its ability to account for the interaction between the vegetation and the flow, taking into account velocity, depth of flow, and vegetative conditions (including type, size, stage of maturity, and density of vegetation). Based on the mathematical model, a table is provided to estimate Manning's n value for flow through vegetation.     

A new generation solution model for predicting thermodynamic properties of a multicomponent system from binaries

During the past 3 decades, all solution models that were used to predict thermodynamic properties of a multicomponent system from binaries improperly assumed that the selected binary compositions in a model are independent of the practical system to be treated. This assumption causes problems both in symmetrical and asymmetrical models. In this article, a new solution model has been suggested, which gets rid of this traditional way and assumes that the selected binary compositions should be closely related to the system considered. After introducing a new concept, the “similarity coefficient,” the relation between the selected binary compositions and the composition of the multicomponent system is established and a new model is generated. This new generation model is more reasonable in theoretical considerations, more reliable in practical use, and more realistic in computerization for estimating thermodynamic properties and calculating phase diagrams in a multicomponent system.