930 resultados para false negative rate


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Sakaki, M. (2005). Persons in negative moods often recall their positive experiences to alleviate their affective states. This study investigated the nature of autobiographical memories that facilitate improvement of negative moods. More specifically, it examined the relations between participants' subjective moods and the three natures of recalled memories (the current positivity, the past positivity, and the importance). After 67 participants were induced either negative or neutral moods, they were asked to recall five positive experiences and to rate their affective states. Results indicated that the more important memories participants recalled, the more positive moods they reported after recollection, and that these effects of the importance of autobiographical memories were observed in both negative and neutral moods. In contrast, neither the current positivity of memories nor the past positivity of memories significantly influenced participant's moods in both negative and neutral moods. The mechanism by which the importance of autobiographical memory affects moods was discussed.

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In contrast to prior studies showing a positive lapse-rate feedback associated with the Arctic inversion, Boé et al. reported that strong present-day Arctic temperature inversions are associated with stronger negative longwave feedbacks and thus reduced Arctic amplification in the model ensemble from phase 3 of the Coupled Model Intercomparison Project (CMIP3). A permutation test reveals that the relation between longwave feedbacks and inversion strength is an artifact of statistical self-correlation and that shortwave feedbacks have a stronger correlation with intermodel spread. The present comment concludes that the conventional understanding of a positive lapse-rate feedback associated with the Arctic inversion is consistent with the CMIP3 model ensemble.

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Objective. Interferences from spatially adjacent non-target stimuli are known to evoke event-related potentials (ERPs) during non-target flashes and, therefore, lead to false positives. This phenomenon was commonly seen in visual attention-based brain–computer interfaces (BCIs) using conspicuous stimuli and is known to adversely affect the performance of BCI systems. Although users try to focus on the target stimulus, they cannot help but be affected by conspicuous changes of the stimuli (such as flashes or presenting images) which were adjacent to the target stimulus. Furthermore, subjects have reported that conspicuous stimuli made them tired and annoyed. In view of this, the aim of this study was to reduce adjacent interference, annoyance and fatigue using a new stimulus presentation pattern based upon facial expression changes. Our goal was not to design a new pattern which could evoke larger ERPs than the face pattern, but to design a new pattern which could reduce adjacent interference, annoyance and fatigue, and evoke ERPs as good as those observed during the face pattern. Approach. Positive facial expressions could be changed to negative facial expressions by minor changes to the original facial image. Although the changes are minor, the contrast is big enough to evoke strong ERPs. In this paper, a facial expression change pattern between positive and negative facial expressions was used to attempt to minimize interference effects. This was compared against two different conditions, a shuffled pattern containing the same shapes and colours as the facial expression change pattern, but without the semantic content associated with a change in expression, and a face versus no face pattern. Comparisons were made in terms of classification accuracy and information transfer rate as well as user supplied subjective measures. Main results. The results showed that interferences from adjacent stimuli, annoyance and the fatigue experienced by the subjects could be reduced significantly (p < 0.05) by using the facial expression change patterns in comparison with the face pattern. The offline results show that the classification accuracy of the facial expression change pattern was significantly better than that of the shuffled pattern (p < 0.05) and the face pattern (p < 0.05). Significance. The facial expression change pattern presented in this paper reduced interference from adjacent stimuli and decreased the fatigue and annoyance experienced by BCI users significantly (p < 0.05) compared to the face pattern.

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Interferences from the spatially adjacent non-target stimuli evoke ERPs during non-target sub-trials and lead to false positives. This phenomenon is commonly seen in visual attention based BCIs and affects the performance of BCI system. Although, users or subjects tried to focus on the target stimulus, they still could not help being affected by conspicuous changes of the stimuli (flashes or presenting images) which were adjacent to the target stimulus. In view of this case, the aim of this study is to reduce the adjacent interference using new stimulus presentation pattern based on facial expression changes. Positive facial expressions can be changed to negative facial expressions by minor changes to the original facial image. Although the changes are minor, the contrast will be big enough to evoke strong ERPs. In this paper, two different conditions (Pattern_1, Pattern_2) were used to compare across objective measures such as classification accuracy and information transfer rate as well as subjective measures. Pattern_1 was a “flash-only” pattern and Pattern_2 was a facial expression change of a dummy face. In the facial expression change patterns, the background is a positive facial expression and the stimulus is a negative facial expression. The results showed that the interferences from adjacent stimuli could be reduced significantly (P<;0.05) by using the facial expression change patterns. The online performance of the BCI system using the facial expression change patterns was significantly better than that using the “flash-only” patterns in terms of classification accuracy (p<;0.01), bit rate (p<;0.01), and practical bit rate (p<;0.01). Subjects reported that the annoyance and fatigue could be significantly decreased (p<;0.05) using the new stimulus presentation pattern presented in this paper.

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OBJECTIVE: Interferences from spatially adjacent non-target stimuli are known to evoke event-related potentials (ERPs) during non-target flashes and, therefore, lead to false positives. This phenomenon was commonly seen in visual attention-based brain-computer interfaces (BCIs) using conspicuous stimuli and is known to adversely affect the performance of BCI systems. Although users try to focus on the target stimulus, they cannot help but be affected by conspicuous changes of the stimuli (such as flashes or presenting images) which were adjacent to the target stimulus. Furthermore, subjects have reported that conspicuous stimuli made them tired and annoyed. In view of this, the aim of this study was to reduce adjacent interference, annoyance and fatigue using a new stimulus presentation pattern based upon facial expression changes. Our goal was not to design a new pattern which could evoke larger ERPs than the face pattern, but to design a new pattern which could reduce adjacent interference, annoyance and fatigue, and evoke ERPs as good as those observed during the face pattern. APPROACH: Positive facial expressions could be changed to negative facial expressions by minor changes to the original facial image. Although the changes are minor, the contrast is big enough to evoke strong ERPs. In this paper, a facial expression change pattern between positive and negative facial expressions was used to attempt to minimize interference effects. This was compared against two different conditions, a shuffled pattern containing the same shapes and colours as the facial expression change pattern, but without the semantic content associated with a change in expression, and a face versus no face pattern. Comparisons were made in terms of classification accuracy and information transfer rate as well as user supplied subjective measures. MAIN RESULTS: The results showed that interferences from adjacent stimuli, annoyance and the fatigue experienced by the subjects could be reduced significantly (p < 0.05) by using the facial expression change patterns in comparison with the face pattern. The offline results show that the classification accuracy of the facial expression change pattern was significantly better than that of the shuffled pattern (p < 0.05) and the face pattern (p < 0.05). SIGNIFICANCE: The facial expression change pattern presented in this paper reduced interference from adjacent stimuli and decreased the fatigue and annoyance experienced by BCI users significantly (p < 0.05) compared to the face pattern.

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In this paper we deal with a Bayesian analysis for right-censored survival data suitable for populations with a cure rate. We consider a cure rate model based on the negative binomial distribution, encompassing as a special case the promotion time cure model. Bayesian analysis is based on Markov chain Monte Carlo (MCMC) methods. We also present some discussion on model selection and an illustration with a real dataset.

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With the rapid increasing number and assets of A-REITs, there has been an urgent need to study the relationship between the changes of cash rates and the A-REITs returns. This study investigates whether there were relationships between Australian-Real Estate Investment Trusts stock returns and policy interest rate changes in the past decade by using event study with a multivariate regression model. The findings indicate that cash rate changes have no significantly positive or negative influence on the equity A-REIT stock prices. A series of successive cash rate changes do not take a continuous and dramatic effect on the equity A-REIT stock prices in each economic cycle. Moreover, the A-REITs with relatively smaller assets show more significant fluctuation to the changes of cash rates, and the A-REITs owning more than $ 10 billion in capital assets have relatively steady stock prices. Overall, the findings from this research lead to a call for comprehensive research into various areas in order to ascertain the determinants of A-REIT price changes.

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Background. There are a large number of factors mediating suicide. Many studies have searched for a direct causal relationship between economic hardship and suicide, however, findings have been varied.

Method. Suicide data was obtained from the Australian Bureau of Statistics for the period between January 1968 and August 2002. These were correlated with a suite of macroeconomic data including housing loan interest rates, unemployment rates, days lost to industrial disputes, Consumer Price Index, gross domestic product, and the Consumer Sentiment Index.

Results.
A total of 51 845 males and 16 327 females committed suicide between these dates. There were significant associations between suicide rates and eleven macroeconomic indicators for both genders in at least one age range. Data was divided into male and female and five age ranges and pooled ages. Analyses were conducted on these 132 datasets resulting in 80 significant findings. The data was generally stronger for indices measuring economic performance than indices measuring consumers’ perceptions of the state of the economy. A striking difference between male and female trends was seen. Generally, male suicide rates increased with markers of economic adversity, while the opposite pattern was seen in females. There were significantly different patterns in age-stratified data, with for example higher housing loan interest rates having a positive association with suicide in younger people and a negative association in older age groups.

Conclusion. Macroeconomic trends are significantly associated with suicide. The patterns in males and females are very different, and there are further substantial age-related differences.

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Background: Investigations of workplace bullying in health care settings have tended to focus on nurses or other clinical staff. However, the organizational and power structures enabling bullying in health care are present for all employees, including administrative staff.

Purposes: The purpose of this study was to specifically focus on health care administration staff and examine the prevalence and consequences of workplace bullying in this occupational group.

Methodology/Approach: A cross-sectional study was conducted based on questionnaire data from health care administration staff who work across facilities within a medium to large health care organization in Australia. The questionnaire included measures of bullying, negative affectivity (NA), job satisfaction, organizational commitment, well-being, and psychological distress. The three hypotheses of the study were that (a) workplace bullying will be linked to negative employee outcomes, (b) individual differences on demographic factors will have an impact on these outcomes, and (c) individual differences in NA will be a significant covariate in the analyses. The hypotheses were tested using t tests and analyses of covariances.

Findings: A total of 150 health care administration staff completed the questionnaire (76% response rate). Significant main effects were found for workplace bullying, with lower organizational commitment and well-being with the effect on commitment remaining over and above NA. Main effects were found for age on job satisfaction and for employment type on psychological distress. A significant interaction between bullying and employment type for psychological distress was also observed. Negative affectivity was a significant covariate for all analyses of covariance.

Practice Implications: The applications of these results include the need to consider the occupations receiving attention in health care to include administration employees, that bullying is present across health care occupations, and that some employees, particularly part-time staff, may need to be managed slightly differently to the full-time workforce.

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Repeatability is an important concept in evolutionary analyses because it provides information regarding the benefit of repeated measurements and, in most cases, a putative upper limit to heritability estimates. Repeatability (R) of different aspects of energy metabolism and behavior has been demonstrated in a variety of organisms over short and long time intervals. Recent research suggests that consistent individual differences in behavior and energy metabolism might covary. Here we present new data on the repeatability of body mass, standard metabolic rate (SMR), voluntary exploratory behavior, and feeding rate in a semiaquatic salamander and ask whether individual variation in behavioral traits is correlated with individual variation in metabolism on a whole-animal basis and after conditioning on body mass. All measured traits were repeatable, but the repeatability estimates ranged from very high for body mass (R = 0.98), to intermediate for SMR (R = 0.39) and food intake (R = 0.58), to low for exploratory behavior (R = 0.25). Moreover, repeatability estimates for all traits except body mass declined over time (i.e., from 3 to 9 wk), although this pattern could be a consequence of the relatively low sample size used in this study. Despite significant repeatability in all traits, we find little evidence that behaviors are correlated with SMR at the phenotypic and among-individual levels when conditioned on body mass. Specifically, the phenotypic correlations between SMR and exploratory behavior were negative in all trials but significantly so in one trial only. Salamanders in this study showed individual variation in how their exploratory behavior changed across trials (but not body mass, SMR, and feed intake), which might have contributed to observed changing correlations across trials.

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© 2015 World Scientific Publishing Co. and Center for Pacific Basin Business, Economics and Finance Research. This study examines whether negative book equity (BE) firms are in financial distress by analyzing their operating performance, financial characteristics, distress risk, and survivability when they first report negative BE. Firms with small magnitude of negative BE (SNBE firms) suffer from persistent negative earnings and financial distress, while firms with large magnitude of negative BE (LNBE firms) experience a temporary non-distress related earnings shock. LNBE firms report consecutive years of negative BE, but have lower distress risk and failure rate than both SNBE and control firms. However, all negative BE stocks have abysmal returns subsequent to their first report of negative BE.

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Context Loss of eggs to predators is a major cause of reproductive failure among birds. It is especially pronounced among ground-nesting birds because their eggs are accessible to a wide range of predators. Few studies document the main causes of clutch fate of ground-nesting birds. Aims The main objective of the present study was to identify the major egg predator of red-capped plovers (Charadrius ruficapillus). We also investigated the effectiveness of the following two primary strategies available to the plovers to avoid egg predation: (1) the placement of clutches under vegetative cover and (2) avoiding predators by nesting outside the peak season of predator occurrence. Methods Remote-sensing cameras were deployed on plover nests to identify egg predators and nests were monitored over four breeding seasons to document reproductive success and fate. An experiment using false clutches with model eggs investigated the influence of nest cover on the risk of egg predation throughout the year. Line-transect surveys were conducted to estimate the abundance of egg predators in and around the wetlands. Key results The little raven (Corvus mellori) was the major egg predator identified in 78.6% of red-capped plover clutches and in 92.4% of false clutches that were camera-monitored. The hatching success of plover eggs was not influenced by nest cover (P≤0.36), but model egg survival in false clutches improved significantly with the presence of nest cover (P≤0.02). The abundance of little ravens increased during the plover breeding season and was highly negatively correlated with false clutch survival (rpearson≤-0.768, P≤0.005). Conclusions Little ravens were the major predator of red-capped plover eggs and their abundance increased significantly during the plover breeding season. Any influence of nest cover on hatching success of eggs may have been masked by the extremely high rate of egg loss associated with the increased little raven abundance during the plover breeding season. Implications The high rate of egg predation is likely to have negative consequences on the local red-capped plover population, suggesting management is warranted. Little raven populations have expanded and, thus, their impact as egg predators needs to be investigated especially on threatened species. Journal compilation

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In this paper we study the interaction between macroeconomic environment and firms’ balance sheet effects in Brazil during the 1990’s. We start by assessing the influence of macroeconomic conditions on firms’ debt composition in Brazil. We found that larger firms tend to change debt currency composition more in response to a change in the exchange rate risk than small firms. We then proceed to investigate if and how exchange rate balance sheet effects affected the firms’ investment decisions. We test directly the exchange rate balance sheet effect on investment. Contrary to earlier findings (Bleakley and Cowan, 2002), we found that firms more indebted in foreign currency tend to invest less when there is an exchange rate devaluation. We tried different controls for the competitiveness effect. First, we control directly for the effect of the exchange rate on exports and imported inputs. We then pursue an alternative investigation strategy, inspired by the credit channel literature. According to this perspective, Tobin’s q can provide an adequate control for the competitiveness effect on investment. Our results provide supporting evidence for imperfect capital markets, and for a negative exchange rate balance sheet effect in Brazil. The results concerning the exchange rate balance sheet effect on investment are statistically significant and robust across the different specifications. We tested the results across different periods, classified according to the macroeconomic environment. Our findings suggest that the negative exchange rate balance sheet effect we found in the whole sample is due to the floating exchange rate period. We also found that exchange rate devaluations have important negative impact on both cash flows and sales of indebted firms. Furthermore, the impact of exchange rate variations is asymmetric, and the significant effect detected when no asymmetry is imposed is engendered by exchange rate devaluations.

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The Exchange Rate is the Most Strategic of the Four Macroeconomic Prices. it Determines not Only Exports and Imports, But Also Real Wages, Consumption and the Savings Rate. Conventional Theory Holds That it is Impossible to Manage It, and That the Only Alternatives are to Fix or to Float It. the Experience of the East Asian Countries, That Use it Strategically, Demonstrates That This Claim is False.

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The aim of this article is to assess the role of real effective exchange rate volatility on long-run economic growth for a set of 82 advanced and emerging economies using a panel data set ranging from 1970 to 2009. With an accurate measure for exchange rate volatility, the results for the two-step system GMM panel growth models show that a more (less) volatile RER has significant negative (positive) impact on economic growth and the results are robust for different model specifications. In addition to that, exchange rate stability seems to be more important to foster long-run economic growth than exchange rate misalignment