2,171 research outputs found
Classification accuracy comparison: hypothesis tests and the use of confidence intervals in evaluations of difference, equivalence and non-inferiority
The comparison of classification accuracy statements has generally been based upon tests of difference or inequality when other scenarios and approaches may be more appropriate. Procedures for evaluating two scenarios with interest focused on the similarity in accuracy values, non-inferiority and equivalence, are outlined following a discussion of tests of difference (inequality). It is also suggested that the confidence interval of the difference in classification accuracy may be used as well as or instead of conventional hypothesis testing to reveal more information about the disparity in the classification accuracy values compared
Mapping the species richness and composition of tropical forests from remotely sensed data with neural networks
The understanding and management of biodiversity is often limited by a lack of data. Remote sensing has considerable potential as a source of data on biodiversity at spatial and temporal scales appropriate for biodiversity management. To-date, most remote sensing studies have focused on only one aspect of biodiversity, species richness, and have generally used conventional image analysis techniques that may not fully exploit the data's information content. Here, we report on a study that aimed to estimate biodiversity more fully from remotely sensed data with the aid of neural networks. Two neural network models, feedforward networks to estimate basic indices of biodiversity and Kohonen networks to provide information on species composition, were used. Biodiversity indices of species richness and evenness derived from the remotely sensed data were strongly correlated with those derived from field survey. For example, the predicted tree species richness was significantly correlated with that observed in the field (r=0.69, significant at the 95% level of confidence). In addition, there was a high degree of correspondence (?83%) between the partitioning of the outputs from Kohonen networks applied to tree species and remotely sensed data sets that indicated the potential to map species composition. Combining the outputs of the two sets of neural network based analyses enabled a map of biodiversity to be produce
Docs Versus Glocks: N.R.A. Takes Aim At Florida Physicians’ Freedom of Speech: Leaving Patients’ Health, Safety, and Welfare At Risk
Part I of this Note provides background on the Act at issue, its legislative history, the current status of the Supreme Court’s free speech jurisprudence, and it also introduces the constitutional interests at stake. Part II considers the constitutionality of the Act under the existing First Amendment standard and addresses the State’s assertions under the Second Amendment. Part III proposes that the Court’s standard ought to be recalibrated, taking into account the would-be listeners’ cognizable interest in the information. Part III goes on to legitimate the proposal by reconciling this new examination standard with existing free speech jurisprudence and justifications, along with a brief exposition of the likeness between the Note’s proposal and the doctrine of informed consent
An Empirical Investigation of Self: Bridging the Gap between ACT, Mindfulness and RFT
The current programme of research had four main aims. First, we hoped to extend existing
work on experimentally induced distress with non-clinical samples of adult participants (male
and female college students aged approximately 18-50 years), with a particular focus on
finding an appropriate preparation that would lend itself to the exploration of brief
therapeutic interventions. Second, we investigated the impact of techniques referred to as self
as context in terms of ameliorating distress induced by the single-sentence preparation. Third,
we compared effects of mindfulness and self as context techniques on distress reduction, and
subsequently investigated effects of individual components of mindfulness. Finally, we
explored the potential role of concepts derived from relational frame theory (RFT) in
enhancing self as context techniques.
Experiment 1 systematically compared a single-sentence preparation first proposed by
Rachman, Shafran, Mitchell, Trant and Teachman (1996) to a multi-sentence distress
induction procedure with a nonclinical sample of undergraduate participants (N = 64). The
experiment was interested in determining which procedure was more effective in inducing
distress (i.e. discomfort, anxiety and stress). Visual Analogue Scales (VASs) were used to
measure changes in these dependent measures. We predicted that the multi-sentence
preparation would generate greater distress. However, statistical analysis including a series of
mixed between within analysis of variance (ANOVA’s) demonstrated that the preparations
were equally effective in inducing emotional distress.
The single-sentence distress induction procedure was employed again in Experiments
2-5 (N = 90). These studies also incorporated a number of brief analogue interventions
derived from acceptance and commitment therapy (ACT). Put simply, the research question
was: Would ACT interventions that targeted acceptance, defusion, values and contact with
the present moment successfully ameliorate experimentally induced distress in a non-clinical
sample of undergraduates. We also investigated whether each of these individual ACT
components would be enhanced by a self as context technique. Similar to Experiment 1,
VASs were used to measure any changes in discomfort, anxiety and stress as a result of the
interventions. We hypothesised that the combined interventions (e.g. self-enhanced
acceptance) would reduce distress more effectively. However, a series of mixed between
within ANOVA’s demonstrated that all interventions, either stand alone components or
combined with self as context, had little or no effect on levels of induced distress.
In Experiments 6-8, we employed an alternative form of distress induction to previous
experiments with a nonclinical sample of undergraduate participants (N = 80). In Experiment
6 we investigated the impact of mindfulness versus self as context techniques in reducing
distress (i.e. discomfort, anxiety and stress) in a non-clinical sample as measured on the
VASs (N = 30). We did not make any specific predictions about the outcomes, but were
concerned with the possibility of differentiated outcomes based on the fact that self as context
techniques encourage a focus on psychological events (i.e. thoughts), while mindfulness
techniques encourage a focus on somatic events (i.e. the body). A series of mixed between
within ANOVA’s demonstrated that both interventions were equally effective in reducing
distress.
In Experiment 7, we distinguished between two mindfulness-based exercises, physical
mindfulness and verbal mindfulness, and thereafter investigated which of these would be
more effective in reducing distress (e.g. discomfort) in a non-clinical sample (N = 26) of
undergraduates (as measured by the VASs). Again, we refrained from making specific
predictions about potentially different outcomes for the two mindfulness-based components
because there are no such experimental comparisons available in the research literature to
date. A series of mixed between within ANOVA’s demonstrated that both conditions reduced
distress as measured via VASs and the difference in distress levels prior and subsequent to
intervention was statistically significant.
In Experiment 8, we turned our attention to an investigation of effects of sequence of
mindfulness exercises and to the possibility that combining physical and verbal mindfulness
exercises would enhance effects observed with either exercises individually. We
hypothesised that the sequence which presented physical mindfulness followed by verbal
mindfulness would show greater reductions in distress (as measured by the VASs) than the
reverse because this is the format employed in most mindfulness-based therapeutic packages
(e.g. Mindfulness-Based Stress Reduction). A series of mixed between within ANOVA’s
demonstrated that this prediction was upheld with our non-clinical sample of (N = 24),
undergraduates and although both conditions resulted in reduced scores on all measures of
distress, the physical-verbal sequence demonstrated superiority.
Experiments 9 and 10 employed the same distress induction procedure and a similar
non-clinical sample of undergraduates as Experiments 6-8 in an effort to investigate the role
of RFT in ACT exercises (N = 84). In particular, in Experiment 9 we investigated distinction
and hierarchical relations when targeted specifically in a self as context exercise (N = 36).
We hypothesised that the hierarchical self as context intervention would show superiority
over the distinction self as context condition in terms of reductions in discomfort, anxiety and
stress, based on previous research by Luciano et al. (2011). A series of mixed between-within
ANOVA’s demonstrated results that were consistent with this prediction as the hierarchical
intervention was the more effective in reducing distress as measured by the VASs.
Experiment 10 attempted to explore this issue further using a different ACT exercise
with undergraduate participants (N = 48). Participants were also exposed to a practice interval
placed between two exposures to the distress induction task, to determine potentially lasting
impacts of the interventions. A second aspect of the research examined the extent to which a
focus on the self played a specific role in the outcomes described above. Accordingly,
Experiment 10 compared interventions that focused on participants’ thoughts about a specific
self-criticism (i.e. self-focused) versus interventions that focused on thoughts about an
inanimate object (i.e. object-focused). We hypothesised that the self-based hierarchical
intervention would be the most effective in terms of distress reduction (e.g. discomfort)
because it aimed to target both self-specific content and hierarchical relations. This prediction
was somewhat supported as statistical analysis demonstrated that both hierarchical conditions
showed superiority in terms of distress reduction compared to both distinction conditions.
Furthermore, both hierarchical conditions were associated with significantly less avoidance in
the second exposure to the distress induction task.
In the General Discussion the current thesis discusses the implications of the research
and extending the existing literature on experimental distress induction procedures, ACT,
mindfulness and RFT
An assessment of citizen contributed ground reference data for land cover map accuracy assessment
It is now widely accepted that an accuracy assessment should be part of a thematic mapping programme. Authoritative good or best practices for accuracy assessment have been defined but are often impractical to implement. Key reasons for this situation are linked to the ground reference data used in the accuracy assessment. Typically, it is a challenge to acquire a large sample of high quality reference cases in accordance to desired sampling designs specified as conforming to good practice and the data collected are normally to some degree imperfect limiting their value to an accuracy assessment which implicitly assumes the use of a gold standard reference. Citizen sensors have great potential to aid aspects of accuracy assessment. In particular, they may be able to act as a source of ground reference data that may, for example, reduce sample size problems but concerns with data quality remain. The relative strengths and limitations of citizen contributed data for accuracy assessment are reviewed in the context of the authoritative good practices defined for studies of land cover by remote sensing. The article will highlight some of the ways that citizen contributed data have been used in accuracy assessment as well as some of the problems that require further attention, and indicate some of the potential ways forward in the future
Classification accuracy comparison: hypothesis tests and the use of confidence intervals in evaluations of difference, equivalence and non-inferiority
The comparison of classification accuracy statements has generally been based upon tests of difference or inequality when other scenarios and approaches may be more appropriate. Procedures for evaluating two scenarios with interest focused on the similarity in accuracy values, non-inferiority and equivalence, are outlined following a discussion of tests of difference (inequality). It is also suggested that the confidence interval of the difference in classification accuracy may be used as well as or instead of conventional hypothesis testing to reveal more information about the disparity in the classification accuracy values compared
- …