Evidence Of Overestimation Research Articles

Correlation between theoretical knowledge and the difference between self- and teaching doctor-assessment.

The right intuition for self-assessment without overestimating or underestimating oneself compared to theoretical knowledge is a skill that requires conscious practice and is very often paradoxically opposed to the level of knowledge. Self-assessment is an essential skill for dental professionals for lifelong learning and improvement. The objective of our study was to assess the correlation between theoretical knowledge and the difference between self- and teaching doctor-assessment. The app "digital course organizer" for organization and assessment was used for the self- and teaching doctor-assessment of students for each day of patient treatment during the clinical courses at a university hospital. The difference between the self- and teaching doctor-assessment was compared to the score of an initial theoretical written test at the beginning of the eighth semester to assess the correlation between overestimation or underestimation and theoretical knowledge. A total of 309 dental students over four semesters in the clinical study phase (fourth and fifth years; eighth and 10th semesters) participated in the investigation. The overall view of all values showed very low correlations (<0.2) of the assessment difference values of both practical courses for the initial written test. There were very low correlations between the initial written test (theoretical knowledge) and the difference between self- and teaching doctor-assessment as well as no evidence of overestimation and underestimation.

The utility of multilevel models for continuous-time feature selection of spatio-temporal networks

Many models for the analysis of spatio-temporal networks specify time as a series of discrete steps. This either requires evenly spaced measurement times or the aggregation of data into measurement windows. This can lead to the introduction of bias. An alternative is to use continuous-time models, for example, multilevel models. Models capturing complex spatio-temporal variation are often difficult to visualise and interpret. This can be addressed by simplifying the results, for example by extracting ‘features’ of interest (such as maxima or minima) of temporal patterns associated with different network connections.This paper uses simulation to evaluate the accuracy and precision with which b-spline-based multilevel models (a flexible form of continuous-time model that can easily capture complex variation associated with a spatio-temporal network structure) capture the timing and extent of maximum delays to journeys made between pairs of stations in a small railway network.On average models captured the timing and extent of maximum delay with small bias, but there was evidence of overestimation and underestimation of low and high values of these features, respectively. This systematic bias may have partially caused the undercoverage of credible intervals for the pattern features. Alternative model specifications – specifically to capture x-axis random variation, for example – should be considered in future work.

Small-tree volume equations for subtropical hardwood plantation species

ABSTRACT Estimation of stem volume is needed to determine timber yield and forest carbon, but equations to estimate volume from easily assessed inventory measures are lacking for hardwood plantation species in the subtropics. We assessed the merits of three volume equations that combine measurements of tree diameter at breast height (DBH) and total tree height for five hardwood plantation taxa (Corymbia citriodora subsp. variegata, Corymbia hybrids, Eucalyptus cloeziana, E. longirostrata and E. dunnii). Goodness-of-fit statistics indicated that model 1 (comprehensive combined variable equation) and model 2 (the Schumacher and Hall equation) fitted the data well (e.g. adjusted R 2 > 98). Analysis of bias in different diameter classes indicated that these models did not show any systematic bias patterns with tree size. Model 3 (combined variable volume equation) is the least desirable as it showed evidence of overestimation of volume for larger trees in some taxa. Models 1 and 2 provide a useful initial set of volume equations for five potentially important hardwood plantation species in subtropical Queensland. These equations are based on stems with a DBH range of 5−30 cm and hence there is a need to collect data for larger stems (>30 cm DBH) as existing plantations mature.

Baseline training history and effects of methamphetamine on performance of pigeons on an interval-bisection task

Length of baseline training influences how methamphetamine disrupts temporal performance under a peak interval schedule. Acute methamphetamine produces overestimation of time following relatively brief training, but following extended training, methamphetamine produces more general loss of stimulus control. The current study extends the study of training length on the effects of methamphetamine to an interval-bisection procedure. Six pigeons responded under a psychophysical choice procedure in which responses to one key color were correct after presentation of four shorter sample durations and responses to another key color were correct after presentation of four longer sample durations. One group of three pigeons received briefer baseline training (45 sessions), while another group received more extended training (223 sessions) prior to methamphetamine administration. There was no evidence of overestimation of time or generalized loss of stimulus control in either group. Sensitivity (precision of timing) was higher in the group with more extensive training and was disrupted by methamphetamine.

Validation of HRDI MLT winds with meteor radars

Abstract. A validation study of the mesospheric and lower-thermospheric (MLT) wind velocities measured by the High-Resolution Doppler Imager (HRDI) on board the Upper-Atmosphere Research Satellite (UARS) has been carried out, comparing with observations by meteor radars located at Shigaraki, Japan and Jakarta, Indonesia. The accuracy of the HRDI winds relative to the meteor radars is obtained by a series of simultaneous wind measurements at the time of UARS overpasses. Statistical tests on the difference in the wind vectors observed by HRDI and the meteor radars are applied to determine whether the wind speed has been overestimated by HRDI (or underestimated by the MF radars) as previously noticed in HRDI vs. MF radar comparisons. The techniques employed are the conventional t-test applied to the mean values of the paired wind vector components as well as wind speeds, and two nonparametric tests suitable for testing the paired wind speed. The square-root transformation has been applied before the t-tests of the wind speed in order to fit the wind-speed distribution function to the normal distribution. The overall results show little evidence of overestimation by HRDI (underestimation by meteor radars) of wind velocities in the MLT region. Some exceptions are noticed, however, at the altitudes around 88 km, where statistical differences occasionally reach a level of significance of 0.01. The validation is extended to estimate the precision of the wind velocities by both HRDI and meteor radars. In the procedure, the structure function defined by the mean square difference of the observed anomalies is applied in the vertical direction for the profile data. This method assumes the isotropy and the homogeneity of variance for the physical quantity and the homogeneity of variance for the observational errors. The estimated precision is about 6ms–1 for the Shigaraki meteor radar, 15ms–1 for the Jakarta meteor radar, and 20ms–1 for HRDI at 90-km altitude. These values can be used to confirm the statistical significance of the wind field obtained by averaging the observed winds.

The validity of time‐budget studies: A comparison of frequency and diary data in Halifax, Canada

Abstract The validity of time‐budget studies was tested by comparing leisure participation data from the Halifax time‐budget study with similar data obtained from a leisure time recall questionnaire. Care was taken to ensure that the population under consideration in the two data sets was the same. Leisure participation was measured according to the frequency and duration of ten leisure activities. Since the two data sets showed similar rates of participation, some confidence can be placed in the validity of time‐budget studies. This conclusion is further supported by the fact that similar patterns of relationship of leisure activities to sex, age, and education were also obtained. However, there was some evidence of overestimation of socially desirable activities (at least the more frequent ones) by middle class people in the interview recall study. The interview recall technique, on the other hand, is probably superior to the time‐budget technique for infrequently occurring activities.