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Prior Expectations (prior + expectation)
Selected AbstractsLINEAGES WITH LONG DURATIONS ARE OLD AND MORPHOLOGICALLY AVERAGE: AN ANALYSIS USING MULTIPLE DATASETSEVOLUTION, Issue 4 2007Lee Hsiang Liow Lineage persistence is as central to biology as evolutionary change. Important questions regarding persistence include: why do some lineages outlive their relatives, neither becoming extinct nor evolving into separate lineages? Do these long-duration lineages have distinctive ecological or morphological traits that correlate with their geologic durations and potentially aid their survival? In this paper, I test the hypothesis that lineages (species and higher taxa) with longer geologic durations have morphologies that are more average than expected by chance alone. I evaluate this hypothesis for both individual lineages with longer durations and groups of lineages with longer durations, using more than 60 published datasets of animals with adequate fossil records. Analyses presented here show that groups of lineages with longer durations fall empirically into one of three theoretically possible scenarios, namely: (1) the morphology of groups of longer duration lineages is closer to the grand average of their inclusive group, that is, their relative morphological distance is smaller than expected by chance alone, when compared with rarified samples of their shorter duration relatives (a negative group morpho-duration distribution); (2) the relative morphological distance of groups of longer duration lineages is no different from rarified samples of their shorter duration relatives (a null group morpho-duration distribution); and (3) the relative morphological distance of groups of longer duration lineages is greater than expected when compared with rarified samples of their shorter duration relatives (a positive group morpho-duration distribution). Datasets exhibiting negative group morpho-duration distributions predominate. However, lineages with higher ranks in the Linnean hierarchy demonstrate positive morpho-duration distributions more frequently. The relative morphological distance of individual longer duration lineages is no different from that of rarified samples of their shorter duration relatives (a null individual morpho-duration distribution) for the majority of datasets studied. Contrary to the common idea that very persistent lineages are special or unique in some significant way, both the results from analyses of long-duration lineages as groups and individuals show that they are morphologically average. Persistent lineages often arise early in a group's history, even though there is no prior expectation for this tendency in datasets of extinct groups. The implications of these results for diversification histories and niche preemption are discussed. [source] A bird can't fly on one wing: patient views on waiting for hip and knee replacement surgeryHEALTH EXPECTATIONS, Issue 2 2007Barbara L. Conner-Spady PhD Abstract Objectives, To obtain patients' perspectives on acceptable waiting times for hip or knee replacement surgery. Methods, A questionnaire with both open- and close-ended items was mailed to 432 consecutive patients who had hip or knee replacement surgery 3,12 months previously in Saskatchewan, Canada. A content analysis was used to analyse the text data from the open-ended questions. Results, The sample of 303 (response rate 70%) was 59% female with a mean age of 70 years (SD 11). The median waiting time from the decision date to surgery was 17 weeks. Individuals who rated their waiting time very acceptable (48%) had a median waiting time of 13 weeks compared with a median waiting time of 22 weeks for those who rated it unacceptable (23%). The two most common determinants of acceptability were patient expectations and pain and its impact on patient quality of life. The median maximum acceptable waiting time was 13 weeks and median ideal waiting time, 8.6 weeks. Seventy-nine per cent felt that those in greater need (higher severity) should go before them on the waiting list. Patient ratings of maximum acceptable waiting time were based on: pain and loss of mobility, time needed to prepare for surgery, and severity at the time of seeing the surgeon. In consideration of changing their surgeon to one with a shorter waiting list, 68% would not. Conclusions, Patient views on waiting times are not only related to quality of life issues, but also to prior expectations and notions of fairness and priority. Understanding patient views on waiting for surgery has implications for better management of waiting times and experiences for joint replacement. [source] Predicting river water temperatures using stochastic models: case study of the Moisie River (Québec, Canada)HYDROLOGICAL PROCESSES, Issue 1 2007Behrouz Ahmadi-Nedushan Abstract Successful applications of stochastic models for simulating and predicting daily stream temperature have been reported in the literature. These stochastic models have been generally tested on small rivers and have used only air temperature as an exogenous variable. This study investigates the stochastic modelling of daily mean stream water temperatures on the Moisie River, a relatively large unregulated river located in Québec, Canada. The objective of the study is to compare different stochastic approaches previously used on small streams to relate mean daily water temperatures to air temperatures and streamflow indices. Various stochastic approaches are used to model the water temperature residuals, representing short-term variations, which were obtained by subtracting the seasonal components from water temperature time-series. The first three models, a multiple regression, a second-order autoregressive model, and a Box and Jenkins model, used only lagged air temperature residuals as exogenous variables. The root-mean-square error (RMSE) for these models varied between 0·53 and 1·70 °C and the second-order autoregressive model provided the best results. A statistical methodology using best subsets regression is proposed to model the combined effect of discharge and air temperature on stream temperatures. Various streamflow indices were considered as additional independent variables, and models with different number of variables were tested. The results indicated that the best model included relative change in flow as the most important streamflow index. The RMSE for this model was of the order of 0·51 °C, which shows a small improvement over the first three models that did not include streamflow indices. The ridge regression was applied to this model to alleviate the potential statistical inadequacies associated with multicollinearity. The amplitude and sign of the ridge regression coefficients seem to be more in agreement with prior expectations (e.g. positive correlation between water temperature residuals of different lags) and make more physical sense. Copyright © 2006 John Wiley & Sons, Ltd. [source] Managing heritage attractions: marketing challenges at sensitive historical sitesINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 6 2002Nathan K. Austin Abstract Historical sites now feature strongly as sites of visitation. However, such sites are often connected with historical events, which are sensitive to visitors and thus highly contentious when utilised in the development of tourism. The paper, from the perspective of the visitor, examines some of the critical issues that generally determine the nature of visitation at sensitive historical sites. The issues identified are the visitor's emotional state at the site, prior expectations of the site and what is to be learnt and perception of site presentation and interpretation. They also include the primary visitor objective to learn about the site, the ease with which access to the site can be obtained and the existence of social experiences between relevant visitor groups that may be extended to the site. The issues identified place significant challenges on how marketers communicate with potential visitors and other stakeholders of the site and require the marketing function to take cognisance of the different emotional states of visitors. Similarly, the nature of the packaging of the site, the channels of visitor access to be encouraged and how pricing is to be used as a marketing tool in a way that it is appropriate for the different groups of visitors to the site, all present unique marketing challenges. Copyright © 2002 John Wiley & Sons, Ltd. [source] Expectations, performance, and citizen satisfaction with urban servicesJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 3 2004Gregg G. Van Ryzin The expectancy disconfirmation model has dominated private-sector research on customer satisfaction for several decades, yet it has not been applied to citizen satisfaction with urban services. The model views satisfaction judgments as determined,not just by product or service performance,but by a process in which consumers compare performance with their prior expectations. Using data from a New York City citizen survey, this study finds that citizen expectations, and especially the disconfirmation of expectations,factors that previously have not been considered in empirical studies of the determinants of citizen satisfaction,play a fundamental role in the formation of satisfaction judgments regarding the quality of urban services. Interestingly, the modeling results suggest that urban managers should seek to promote not only high-quality services, but also high expectations among citizens. Additional implications for research and public management practice are discussed. © 2004 by the Association for Public Policy Analysis and Management. [source] CONSUMER EXPECTATIONS AND PERCEPTION OF CHOCOLATE MILK DESSERTS ENRICHED WITH ANTIOXIDANTSJOURNAL OF SENSORY STUDIES, Issue 2010GASTÓN ARES ABSTRACT A study was carried out to identify consumers' previous expectations of chocolate milk desserts enriched with antioxidants and to determine if these expectations affected product perception. Seventy-five consumers participated in the study and were asked to complete a word association task before the evaluation. Then, consumers tried six milk desserts with different polyphenolic concentration, scored their overall liking and willingness to purchase and provided up to four words to describe each of the samples. Cluster analysis performed on consumer-elicited terms in the word association task allowed the identification of three consumer segments with different expectations and motivations toward chocolate milk desserts enriched with antioxidants. These groups also differed in their evaluation of the desserts when tasting them, showing different overall liking, willingness to purchase and sensory description of the samples. This suggests that consumers' prior expectations and motivations significantly affected their response when tasting the desserts. PRACTICAL APPLICATIONS Word association was used to get an insight on consumer expectations of chocolate milk desserts enriched with antioxidants, proving to be a useful methodology. This approach could be a simple technique to understand consumer expectations before tasting a product, and to study how these expectations affect their response after tasting the product, particularly interesting when novel products are considered. Consumer segmentation based on their previous thoughts about a product could help to assure that a product meets consumer expectations appropriately, leading to a higher satisfaction. [source] Extra pair paternity in birds: a review of interspecific variation and adaptive functionMOLECULAR ECOLOGY, Issue 11 2002Simon C. Griffith Abstract The application of molecular genetic techniques has revolutionized our view of avian mating systems. Contrary to prior expectations, birds are only very rarely sexually monogamous, with ,extra-pair offspring' found in approximately 90% of species. Even among socially monogamous species, over 11% of offspring are, on average, the result of extra-pair paternity (EPP). Based on over 150 molecular genetic studies of EPP in birds, we review two topical areas: (i) ecological explanations for interspecific variation in the rate of EPP; and (ii) evidence bearing on the adaptive function of EPP. We highlight the remaining challenges of understanding the relative roles of genes and ecology in determining variation between taxa in the rate of extra paternity, and testing for differences between extra-pair offspring and those sired within-pair. [source] Characterization of dinucleotide microsatellite markers in the parthenogenetic mourning gecko (Lepidodactylus lugubris)MOLECULAR ECOLOGY RESOURCES, Issue 3 2003C. D. Wilmhoff Abstract We present 16 variable dinucleotide microsatellite markers to quantify genetic variation in the parthenogenetic gecko, Lepidodactylus lugubris. Genetic diversity at these loci was unusually high for an asexual species. Subsets of individuals produced identical genotypes across all loci. Individual loci revealed evidence of polyploidy and marked differences between observed and expected heterozygosity, indicating the presence of null alleles. These patterns conform to prior expectations based on the distant genetic relationships between the presumed sexual progenitors of L. lugubris. Comparisons with sexual relatives will be required to determine the sources of the observed genetic variation. [source] Applicant Considerations Associated with Selection of an Emergency Medicine Residency ProgramACADEMIC EMERGENCY MEDICINE, Issue 4 2009Sara Laskey MD Abstract Objectives:, The primary objective of this study was to assess variables that residency applicants ranked as influential in making residency choices. The secondary objective was to determine if residents were satisfied with their residency choices. Methods:, A secondary analysis was performed on a cohort database from a stratified, random sampling of 322 emergency medicine (EM) residents collected in 1996,1998 and 2001,2004 from the American Board of Emergency Medicine Longitudinal Study on Emergency Medicine Residents (ABEM LSEMR). Residents rated the importance of 18 items in response to the question, "How much did each of the following factors influence your choice of residency program location?" The degree to which residents' programs met prior expectations and the levels of satisfaction with residency programs were also assessed. All analyses were conducted using descriptive statistics. Results:, Three-hundred twenty-two residents participated in the survey. Residents considered the following to be the most important variables: institutional reputation, hospital facilities, program director reputation, and spousal influence. Several geographic and gender differences were noted. Ninety percent (95% confidence interval [CI] = 86% to 93%) of residents surveyed in their final year answered that the residency program met or exceeded expectations. Seventy-nine percent (95% CI = 76% to 82%) of residents identified themselves as "highly satisfied" with their residency choice. Conclusions:, The most influential factors in residency choice are institutional and residency director reputation and hospital facilities. Personal issues, such as recreational opportunities and spousal opinion, are also important, but are less influential. Significant geographic differences affecting residency choices exist, as do minor gender differences. A majority of residents were highly satisfied overall with their residency choices. [source] On Smoothing Trends in Population Index ModelingBIOMETRICS, Issue 4 2007Chiara Mazzetta Summary In this article, we consider the U.K. Common Birds Census counts and their use in monitoring bird abundance. We use a state,space modeling approach within a Bayesian framework to describe population level trends over time and contribute to the alert system used by the British Trust for Ornithology. We account for potential overdispersion and excess zero counts by modeling the observation process with a zero-inflated negative binomial, while the system process is described by second-order polynomial growth models. In order to provide a biological motivation for the amount of smoothing applied to the observed series the system variance is related to the demographic characteristics of the species, so as to help the specification of its prior distribution. In particular, the available information on productivity and survival is used to formulate prior expectations on annual percentage changes in the population level and then used to constrain the variance of the system process. We discuss an example of how to interpret alternative choices for the degree of smoothing and how these relate to the classification of species, over time, into conservation lists. [source] | ||||||||||||||||