Bias-induced threshold voltages shifts in thin-film organic transistors

An investigation into the stability of metal-insulator-semiconductor (MIS) transistors based on alpha-sexithiophene is reported. In particular, the kinetics of the threshold voltage shift upon application of a gate bias has been determined. The kinetics follow stretched-hyperbola-type behavior, in agreement with the formalism developed to explain metastability in amorphous-silicon thin-film transistors. Using this model, quantification of device stability is possible. Temperature-dependent measurements show that there are two processes involved in the threshold voltage shift, one occurring at Tapproximate to220 K and the other at Tapproximate to300 K. The latter process is found to be sample dependent. This suggests a relation between device stability and processing parameters. (C) 2004 American Institute of Physics.

Bias in peripheral depression biomarkers

BACKGROUND: To aid in the differentiation of individuals with major depressive disorder (MDD) from healthy controls, numerous peripheral biomarkers have been proposed. To date, no comprehensive evaluation of the existence of bias favoring the publication of significant results or inflating effect sizes has been conducted. METHODS: Here, we performed a comprehensive review of meta-analyses of peripheral nongenetic biomarkers that could discriminate individuals with MDD from nondepressed controls. PubMed/MEDLINE, EMBASE, and PsycINFO databases were searched through April 10, 2015. RESULTS: From 15 references, we obtained 31 eligible meta-analyses evaluating biomarkers in MDD (21,201 cases and 78,363 controls). Twenty meta-analyses reported statistically significant effect size estimates. Heterogeneity was high (I2 ≥ 50%) in 29 meta-analyses. We plausibly assumed that the true effect size for a meta-analysis would equal the one of its largest study. A significant summary effect size estimate was observed for 20 biomarkers. We observed an excess of statistically significant studies in 21 meta-analyses. The summary effect size of the meta-analysis was higher than the effect of its largest study in 25 meta-analyses, while 11 meta-analyses had evidence of small-study effects. CONCLUSIONS: Our findings suggest that there is an excess of studies with statistically significant results in the literature of peripheral biomarkers for MDD. The selective publication of 'positive studies' and the selective reporting of outcomes are possible mechanisms. Effect size estimates of meta-analyses may be inflated in this literature.

Social desirability bias in the reporting of alcohol consumption: a randomized trial

OBJECTIVE: To investigate reporting of alcohol consumption, we manipulated the contexts of questions in ways designed to induce social desirability bias. METHOD: We undertook a two-arm, parallel-group, individually randomized trial at an Australian public university. Students were recruited by email to a web-based "Research Project on Student Health Behavior." Respondents answered nine questions about their physical activity, diet, and smoking. They were unknowingly randomized to a group presented with either (A) three questions about their alcohol consumption or (B) seven questions about their alcohol dependence and problems (under a prominent header labeled "Alcohol Use Disorders Identification Test"), followed by the same three alcohol consumption questions from (A). RESULTS: A total of 3,594 students (mean age = 27, SD = 10) responded and were randomized: 1,778 to Group A and 1,816 to Group B. Outcome measures were the number of days they drank alcohol, the typical number of drinks they consumed per drinking day, and the number of days they consumed six or more drinks. The primary analysis included participants with any alcohol consumption in the preceding 4 weeks (1,304 in Group A; 1,340 in Group B) using between-group, two-tailed t tests. RESULTS: In Groups A and B, respectively, means (and SDs) of the number of days drinking were 5.89 (5.92) versus 6.06 (6.12), p = .49; typical number of drinks per drinking day: 4.02 (3.87) versus 3.82 (3.76), p = .17; and number of days consuming six or more drinks: 1.69 (2.94) versus 1.67 (3.25), p = .56. CONCLUSIONS: We could not reject the null hypothesis because earlier questions about alcohol dependence and problems showed no sign of biasing the respondents' subsequent reports of alcohol consumption. These data support the validity of university students' reporting of alcohol consumption in web-based studies.

A systemist approach to the analysis of gender gender bias in Iranian high school English textbooks

This chapter aims to see if English textbooks written for high school students in Iran are in favor of a particular gender. To this end, four English textbooks currently taught in the Iranian high schools were analysed on the basis of Systemic Functional Linguistics. Five categories were identified and two types of analyses were conducted- content analysis and linguistic. The result of the content analysis demonstrated a significant difference between the frequencies in male-female distribution. The linguistic analysis revealed that there are more males in theme and rheme positions as well as participants role, expecting for the Sensor role, The differences could be attributed to the writers' attitudes, culture, and patriarchal structure of the Iranian families.

When Catholics turn right: the effects of the Islamic terrorism threat on the fragmented Catholic Italian voters

Italy, as well as most European countries, has been hit by a wave of anxiety arising from groups such as ISIS and Al Qaeda, whose effects on political attitudes are still under-examined. This article investigates the effect of the perceived threat of Islamic terrorism as a potential driver for a ‘right turn’ in the Catholic Italian electorate with open-ended interviews and an Internet-based experiment in which voters were randomly assigned to a terrorism threat manipulation and to a control condition (N = 138). The results show that the Islamic terroristic threat significantly increased the support for centre-right leaders who promoted in-group identity and out-group hostility towards Muslims. Implications for the debate about the effects of perceived threat on political opinions and the relevance of the findings beyond the Italian case are discussed at the end of the article.

Bias in emerging biomarkers for bipolar disorder

BACKGROUND: To date no comprehensive evaluation has appraised the likelihood of bias or the strength of the evidence of peripheral biomarkers for bipolar disorder (BD). Here we performed an umbrella review of meta-analyses of peripheral non-genetic biomarkers for BD. METHOD: The Pubmed/Medline, EMBASE and PsycInfo electronic databases were searched up to May 2015. Two independent authors conducted searches, examined references for eligibility, and extracted data. Meta-analyses in any language examining peripheral non-genetic biomarkers in participants with BD (across different mood states) compared to unaffected controls were included. RESULTS: Six references, which examined 13 biomarkers across 20 meta-analyses (5474 BD cases and 4823 healthy controls) met inclusion criteria. Evidence for excess of significance bias (i.e. bias favoring publication of 'positive' nominally significant results) was observed in 11 meta-analyses. Heterogeneity was high for (I 2 ⩾ 50%) 16 meta-analyses. Only two biomarkers met criteria for suggestive evidence namely the soluble IL-2 receptor and morning cortisol. The median power of included studies, using the effect size of the largest dataset as the plausible true effect size of each meta-analysis, was 15.3%. CONCLUSIONS: Our findings suggest that there is an excess of statistically significant results in the literature of peripheral biomarkers for BD. Selective publication of 'positive' results and selective reporting of outcomes are possible mechanisms.

SAMPLING BIAS IN EVALUATING THE PROBABILITY OF SEISMICALLY INDUCED SOIL LIQUEFACTION WITH SPT & CPT CASE HISTORIES

Several deterministic and probabilistic methods are used to evaluate the probability of seismically induced liquefaction of a soil. The probabilistic models usually possess some uncertainty in that model and uncertainties in the parameters used to develop that model. These model uncertainties vary from one statistical model to another. Most of the model uncertainties are epistemic, and can be addressed through appropriate knowledge of the statistical model. One such epistemic model uncertainty in evaluating liquefaction potential using a probabilistic model such as logistic regression is sampling bias. Sampling bias is the difference between the class distribution in the sample used for developing the statistical model and the true population distribution of liquefaction and non-liquefaction instances. Recent studies have shown that sampling bias can significantly affect the predicted probability using a statistical model. To address this epistemic uncertainty, a new approach was developed for evaluating the probability of seismically-induced soil liquefaction, in which a logistic regression model in combination with Hosmer-Lemeshow statistic was used. This approach was used to estimate the population (true) distribution of liquefaction to non-liquefaction instances of standard penetration test (SPT) and cone penetration test (CPT) based most updated case histories. Apart from this, other model uncertainties such as distribution of explanatory variables and significance of explanatory variables were also addressed using KS test and Wald statistic respectively. Moreover, based on estimated population distribution, logistic regression equations were proposed to calculate the probability of liquefaction for both SPT and CPT based case history. Additionally, the proposed probability curves were compared with existing probability curves based on SPT and CPT case histories.

BIAS-CORRECTED MAXIMUM LIKELIHOOD ESTIMATION OF THE PARAMETERS OF THE WEIGHTED LINDLEY DISTRIBUTION

This report discusses the calculation of analytic second-order bias techniques for the maximum likelihood estimates (for short, MLEs) of the unknown parameters of the distribution in quality and reliability analysis. It is well-known that the MLEs are widely used to estimate the unknown parameters of the probability distributions due to their various desirable properties; for example, the MLEs are asymptotically unbiased, consistent, and asymptotically normal. However, many of these properties depend on an extremely large sample sizes. Those properties, such as unbiasedness, may not be valid for small or even moderate sample sizes, which are more practical in real data applications. Therefore, some bias-corrected techniques for the MLEs are desired in practice, especially when the sample size is small. Two commonly used popular techniques to reduce the bias of the MLEs, are ‘preventive’ and ‘corrective’ approaches. They both can reduce the bias of the MLEs to order O(n−2), whereas the ‘preventive’ approach does not have an explicit closed form expression. Consequently, we mainly focus on the ‘corrective’ approach in this report. To illustrate the importance of the bias-correction in practice, we apply the bias-corrected method to two popular lifetime distributions: the inverse Lindley distribution and the weighted Lindley distribution. Numerical studies based on the two distributions show that the considered bias-corrected technique is highly recommended over other commonly used estimators without bias-correction. Therefore, special attention should be paid when we estimate the unknown parameters of the probability distributions under the scenario in which the sample size is small or moderate.

Constructing Threat: How Americans Identify Economic Competitors

China’s emergence as an economic powerhouse has often been portrayed as threatening to America’s economic strength and to its very identity as “the global hegemon.” The media’s alarmist response to an economic competitor is familiar to those who remember US-Japanese relations in the 1980s. In order to better understand the basis of American threat perception, this study explores the independent and interactive impact of three variables (perceptions of the Other’s capabilities, perceptions of the Other as a threat versus as an opportunity, and perceptions of the Other’s political culture) on attitudes toward two different economic competitors (Japan 1977-1995 and China 1985-2011). Utilizing four methods (historical process tracing, public polling data analysis, social scientific experimentation, and content analysis), this study demonstrates that increases in the Other’s economic capabilities have a much smaller impact on attitudes than is commonly believed. It further shows that while perceptions of threat/opportunity played a significant role in shaping attitudinal response toward Japan, perceptions of political culture are the most important factor driving attitudes toward China today. This study contributes to a better understanding of how states react to threats and construct negative images of their economic rivals. It also helps to explain the current Sino-American relationship and enables better predictions as to its potential future course. Finally, these findings contribute to cultural explanations of the democratic peace phenomenon and provide a boundary condition (political culture) for the liberal proposition that opportunity ameliorates conflict in the economic realm.

In the name of humanity: the government of threat and care

In this volume, editors Ilana Feldman and Miriam Ticktin have drawn together an outstanding collection of essays exploring the concept of ‘humanity’ in a range of contexts and from a rich variety of perspectives. Tracing the categorisation of humanity throughout history in their introductory chapter, Feldman and Ticktin highlight the perennial tension inherent in its definition and use. The ever-shifting boundaries of humanity serve to include and protect even as they reject and threaten those identified as ‘other’. Each of the eleven chapters engages with the fundamental question of what it means to be human, and the implications of possible responses to this for the practice of governance. However, despite the pervasive theme of government— which is explored explicitly in the context of humanitarian law (Richard Ashby Wilson) and aid (Didier Fassin), healthcare (Joao Biehl; S. Lochlann Jain; Adriana Petryna), and the regulation of human interactions with nature (Arun Agrawal; Charles Zerner)—it is the more personal aspect of the human experience that takes centre stage in most chapters, and which offers the deepest insights into that elusive concept: ‘humanity’. It offers readers a multifaceted and open-ended account of humanity, which will inform better governance and more effective research in this field.

The threat of autocracy diffusion in consolidated democracies? The case of China, Singapore and Australia

The majority of today’s authoritarian regimes have little hope of promoting autocracy beyond their own borders, let alone to consolidated democratic countries. However, China and Singapore are two prominent examples of non-democratic countries whose soft power arsenals have given them some global appeal beyond that enjoyed by most authoritarian regimes. But to what extent has China’s and Singapore’s power of example influenced consolidated democracies in terms that the latter wanting to replicate some political practices or even norms in these non-democratic regimes? In this article, we engage recent works to examine this question in relation to how Australians perceive the political example offered by China and Singapore. Focusing our analysis on several prominent polls conducted recently by the Lowy Institute for International Policy, we suggest that at present there is little evidence of a causal impact of the rise of authoritarian powerhouses such as China and Singapore on how Australians view democracy at home. Through these case studies, this article sheds some light on the theoretical as well as practical questions about the inherent impediments of authoritarian diffusion in consolidated democracies.

Bias of damage awards and free options in securities litigation

Damage measures in securities fraud cases are very imprecise because they are based on security price changes that reflect both the correction of previous misrepresentation and other independent information. Consequently, potential plaintiffs have a valuable “free option” to decide whether or not to file suit, and average damage awards are greater than actual damages, much greater when markets are volatile. The “Private Securities Litigation Reform Act of 1995” was intended to curb abusive litigation and to address the problem of excessive damage awards. Motivated by a misdiagnosis that excess awards are due to temporary price drops, the Act limits damages to the difference between the purchase price and the time-averaged trading price from the release of the corrective information until 90 days later or until the sale of the security, whichever is first. Unfortunately, the Act's modified measure of damages suffers from a more severe free-option problem than did the traditional measure. Also, the Act introduced an additional new option to time the sale of the security; the effects of these options may be mitigated by the impact of the positive drift in stock prices over time, if the time-averaged price is not adjusted for market movements. As a result, the bias can be larger or smaller under the new Act, depending on how severe the free-option problem is. We propose an alternative approach to addressing the issue of excessive damages: courts should adopt a threshold of measured damages below which no damage would be awarded. The threshold would depend on several factors, most notably the volatility of the stock in the period under question. That is, damages will be awarded only if measured damages exceed the threshold, and awards would be capped by the formula presented in the Reform Act.

Prejudicial evaluation: bias in self-and-peer-assessments of teamwork contributions to design

This chapter considers a simple but important question: can students fairly assess each other’s individual contribution to team designs? The chapter focuses on a key problem when using online self-and-peerassessment to individualising design grades for team assignments, namely rater bias – the possibility of students being biased when assessing their own and their peers’ contributions. Three rater-bias issuesare considered in depth: (1) self-overmarking; (2) gender bias and gender differences; and (3) out-group bias in the peer assessment of international students in multicultural cohorts. Each issue is explored viathe analysis of eight years of quantitative data from the use of an online self-and-peer assessment tool. Evidence is found of self-overmarking and of out-group bias in nonhomogeneous cohorts. However, no evidence is found of gender bias. The chapter concludes with recommendations for design teachers around the assessment of individual contributions to teamwork using self-and-peer assessment.

Assemblage, size and abundance bias in a novel sandy shore macro-infaunal sampling technique

Sampling sandy shore macro-invertebrate fauna is critical in enhancing our understanding of beach ecology and conservation, and is a common monitoring approach. The traditional, and almost universal, method of sampling involves sieving sand to locate infauna, but here we describe a novel Hydraulic Sampling Device (HSD), a candidate method for future macro-invertebrate sampling, which has the potential to be faster and more effective at sampling invertebrates. We compared the results obtained by these two methods. Macro-invertebrate fauna of six beaches on Phillip Island, southern Victoria, Australia were sampled in the upper and lower beach. On average, the HSD sampled a smaller size range of fauna than the sieving method, perhaps because of longer handling times and escape of larger individuals. The sieving method found more individuals and a higher species richness. The methods we describe do not produce directly comparable results. On balance, the sieving method is simpler, apparently not as prone to ‘escape bias’, and reports higher abundances and richness of beach infauna.