Political Divestiture

2018 ◽  
pp. 215-239
Keyword(s):  
Event Study ◽  
Insider Trading ◽  
Negative Impact ◽  
Evaluation Studies ◽  
Meta Analysis ◽  
Sample Selection ◽  
Internal Validity ◽  
Information Leakage ◽  
Future Research ◽  
Stakeholder Pressure

In the wake of historical and political events, stakeholder pressure can trigger divestment from politically incorrect markets. Six evaluation studies of political divestiture from South Africa during Apartheid were meta-analyzed to find a pattern of stakeholder pressure, political divestiture, and corporate endeavors. The meta-analysis covered the question of whether corporations divesting from politically incorrect markets are more likely to experiencing an increase, decrease, or no change in market value, and it found varying results – some studies suggest a positive effect, others a negative impact, and even no overall performance pattern of political divestiture and corporate value was reported. The study also detected a research gap on the impact of political divestiture on corporations operating in politically fractionate markets. Future research may compare values of divesting corporations with those operating in politically incorrect markets. The instringent results are attributed to stem from methodological limitations. Political divestiture is captured by the event study method which was evaluated for validity threats. Internal validity limitations of event study designs stem from confounding and contaminating history occurrences, sample selection biases, and inappropriate time frames. Insider trading information leakage but also industry specificities imply additional validity drawbacks. The external validity is challenged by geographically limited and time-targeted studies as well as non-typical samples that feature a lowered replicability and generalizability of the findings.

scholarly journals Quality of Research Design Moderates Effects of Grade Retention on Achievement: A Meta-Analytic, Multilevel Analysis

2009 ◽  
Vol 31 (4) ◽  
pp. 480-499 ◽  
Author(s):  
Chiharu S. Allen ◽  
Qi Chen ◽  
Victor L. Willson ◽  
Jan N. Hughes
Keyword(s):  
Grade Retention ◽  
Negative Impact ◽  
Meta Analysis ◽  
Median Number ◽  
Effect Sizes ◽  
Future Research ◽  
Negative Effects ◽  
Design Quality ◽  
Individual Level

The present meta-analysis examines the effect of grade retention on academic outcomes and investigates systemic sources of variability in effect sizes. Using multilevel modeling (MLM), the authors investigate characteristics of 207 effect sizes across 22 studies published between 1990 and 2007 at two levels: the study (between) and individual (within) levels. Design quality is a study-level variable. Individual-level variables are median grade retained and median number of years postretention. Quality of design is associated with less negative effects. Years postretention is negatively associated with retention effects, and this effect is stronger for studies using grade comparisons versus age comparisons. The results challenge the widely held view that retention has a negative impact on achievement. Suggestions for future research are discussed.

A meta-analysis of accelerometer sleep outcomes in healthy children based on the Sadeh algorithm: the influence of child and device characteristics

SLEEP ◽  
2020 ◽  
Author(s):  
Jojanneke A M C van Kooten ◽  
Sofie T W Jacobse ◽  
Martijn W Heymans ◽  
Ralph de Vries ◽  
Gertjan J L Kaspers ◽  
...  
Keyword(s):  
Reference Values ◽  
Sleep Problems ◽  
Negative Impact ◽  
Meta Analysis ◽  
Sleep Onset ◽  
Control Sample ◽  
Future Research ◽  
Sleep Onset Latency ◽  
Healthy Children ◽  
General Reference

Abstract Study Objectives Children often experience sleep problems, with a negative impact on mood, behavior, cognitive function, and other aspects of mental and physical health. Accelerometers are widely used to assess sleep, but general reference values for healthy children do not yet exist. The aim of this meta-analysis was to determine mean values for wake after sleep onset (WASO), sleep efficiency (SE), total sleep time (TST) and sleep onset latency (SOL), and to determine the effect of child and accelerometer-characteristics. Methods A search included studies with healthy children, 0–18 years, reporting WASO, SE, TST, and/or SOL, calculated with the Sadeh algorithm. Meta-analyses with random effects produced pooled estimate means per outcome. Meta-regression analyses determined the effect of age, sex, placement site and accelerometer type. Results Eighty-three studies (9,068 participants) were included. Pooled means were 63 min (95% CI 57 to 69) for WASO, 88% (95% CI 87 to 89) for SE, 477 min (95% CI 464 to 491) for TST and 19 min (95% CI 17 to 22) for SOL. Heterogeneity was high (95%–99%). TST decreased with age and there was an age-effect on SOL. SE differed between wrist and ankle (used in age 0–24 months) placement, and between piezoelectric and MEMS-type accelerometers. No differences were found between boys and girls, although this number of studies was small. Conclusions We found differences in almost all investigated outcomes and heterogeneity was high. Therefore, we advise to use a study-specific control sample until more robust reference values are available. Future research should narrow the methodological heterogeneity and produce larger datasets, needed to establish these reference values.

Reversion Toward the Mean Independently of Regression Toward the Mean

Methodology ◽  
2009 ◽  
Vol 5 (1) ◽  
pp. 3-6 ◽  
Author(s):  
Merton S. Krause
Keyword(s):  
Random Error ◽  
Evaluation Studies ◽  
Internal Validity ◽  
Intervention Evaluation ◽  
Population Mean ◽  
Experimental Intervention ◽  
Sample Data ◽  
The Mean ◽  
Regression Toward The Mean

There is another important artifactual contributor to the apparent improvement of persons subjected to an experimental intervention which may be mistaken for regression toward the mean. This is the phenomenon of random error and extreme selection, which does not at all involve the population regression of posttest on pretest scores but involves a quite different and independent reversion of subjects’ scores toward the population mean. These two independent threats to the internal validity of intervention evaluation studies, however, can be detected and differentiated on the sample data of such studies.

Opportunities for improving the insider laws: A comparative analysis of the practice in the USA and Russia

2020 ◽  
Vol 26 (4) ◽  
pp. 796-814
Author(s):  
E.K. Ovakimyan
Keyword(s):  
Financial Markets ◽  
Insider Trading ◽  
Negative Impact ◽  
Business Environment ◽  
Market Manipulation ◽  
Insider Information ◽  
Analysis And Synthesis ◽  
The Usa ◽  
Legislative Perfection ◽  
Definition Of

Subject. The article examines the laws regulating insider trading. Objectives. The study outlines recommendations for refining Law On Countering the Illegal Use of Insider Information and Market Manipulation and Amendments to Some Legislative Acts of the Russian Federation, № 224-ФЗ of July 27, 2010. Methods. The methodological framework includes a general dialectical method, analysis and synthesis, induction and deductions, and some specific methods, such as comparative and formal logic analysis to specify the definition of insider information, structural logic and functional analysis to improve the mechanism for countering insider trading and market manipulation. Results. We discovered key drawbacks to be addressed so as to improve the business environment in Russia. Although the Russia laws mainly mirror the U.S. laws, they present a more extended list of terms concerning the insider information. I believe the legislative perfection should be continued. Conclusions and Relevance. The study helps apply the findings to outline a new legislative regulation or amend the existing ones, add a new mention on the course of financial markets to students’ books, develop new methods for detecting and countering and improving the existing ones. If all parties to insider relationships use the findings, they will prevent insider trading crimes in financial markets and (or) reduce the negative impact of such crimes on the parties.

Applying personalized medicine to adult severe asthma

2021 ◽  
Vol 42 (1) ◽  
pp. e8-e16 ◽  
Author(s):  
Angelica Tiotiu
Keyword(s):  
Personalized Medicine ◽  
Severe Asthma ◽  
Negative Impact ◽  
Target Therapy ◽  
Asthma Management ◽  
Future Research ◽  
Biologic Therapies ◽  
Eosinophilic Asthma ◽  
Definition Of ◽  
Structured Approach

Background: Severe asthma is a heterogeneous disease that consists of various phenotypes driven by different pathways. Associated with significant morbidity, an important negative impact on the quality of life of patients, and increased health care costs, severe asthma represents a challenge for the clinician. With the introduction of various antibodies that target type 2 inflammation (T2) pathways, severe asthma therapy is gradually moving to a personalized medicine approach. Objective: The purpose of this review was to emphasize the important role of personalized medicine in adult severe asthma management. Methods: An extensive research was conducted in medical literature data bases by applying terms such as “severe asthma” associated with “structured approach,” “comorbidities,” “biomarkers,” “phenotypes/endotypes,” and “biologic therapies.” Results: The management of severe asthma starts with a structured approach to confirm the diagnosis, assess the adherence to medications and identify confounding factors and comorbidities. The definition of phenotypes or endotypes (phenotypes defined by mechanisms and identified through biomarkers) is an important step toward the use of personalized medicine in asthma. Severe allergic and nonallergic eosinophilic asthma are two defined T2 phenotypes for which there are efficacious targeted biologic therapies currently available. Non-T2 phenotype remains to be characterized, and less efficient target therapy exists. Conclusion: Despite important progress in applying personalized medicine to severe asthma, especially in T2 inflammatory phenotypes, future research is needed to find valid biomarkers predictive for the response to available biologic therapies to develop more effective therapies in non-T2 phenotype.

META-ANALYSIS ON AMERICAN PRESIDENTIAL ELECTION - 2016 AND AMERICAN STOCK MARKET

2020 ◽  
Vol 38 (1) ◽  
Author(s):  
Farhan Ahmed ◽  
Salman Bahoo ◽  
Sohail Aslam ◽  
Muhammad Asif Qureshi
Keyword(s):  
Content Analysis ◽  
Stock Market ◽  
Event Study ◽  
Presidential Election ◽  
Republican Party ◽  
Stock Exchange ◽  
Meta Analysis ◽  
Composite Index ◽  
Stock Index ◽  
Political Event

This paper aims to analyze the efficient stock market hypothesis as responsive to American Presidential Election, 2016. The meta-analysis has been done combining content analysis and event study methodology. The all major newspapers, news channels, public polls, literature and five important indices as Dow Jones Industrial Average (DJIA), NASDAQ Stock Market Composit Indexe (NASDAQ-COMP), Standard & Poor's 500 Index (SPX-500), New York Stock Exchange Composite Index (NYSE-COMP) and Other U.S Indexes-Russell 2000 (RUT-2000) are critically examined and empirically analyzed. The findings from content analysis reflect that stunned winning of Mr Trump from Republican Party worked as shock for American stock market. From event study, findings confirmed that all the major indices reflected a decline on winning of Trump and losing of Ms. Clinton from Democratic. The results are supported empirically and practically through the political event like BREXIT that resulted in shock to Global stock index and loss of $2 Trillion.

Employees' Perceptions of the Effects of Retrenchment on Job Stress and Organisational Commitment in a Mining Company

2019 ◽  
Vol 43 ◽  
Author(s):  
Landiswa Seteni ◽  
Pierre Joubert ◽  
Manilall Dhurup
Keyword(s):  
Job Stress ◽  
Quantitative Research ◽  
Negative Impact ◽  
Surface Mining ◽  
Future Research ◽  
Global Changes ◽  
Organisational Commitment ◽  
Consultation Process ◽  
Mining Company ◽  
Time Stress

Over the past decade, South African organisations have had to cope with an ever-increasing rate of local and global changes. There have been considerable and ongoing socio-political changes, resulting from new government regulations. Most organisations have experienced some type of downturn, whether due to external business factors or poor internal performance. A typical response to organisational decline is retrenchment. Our study sought to explore employees’ perceptions of the effects of retrenchment on job stress and organisational commitment in a mining company. The study was located within a quantitative research paradigm. Four research hypotheses were posited and data was collected in one region from a sample of 400 surface mining employees, including management, administrators, engineers and artisans. The results showed that the effects of retrenchment did not have a negative impact on job stress (time stress and anxiety). This may be due to the fact that the mining company in question had a planning and consultation process in place for the employees prior to the retrenchment process. The results also showed that job stress (time stress and anxiety) was negatively associated with organisational commitment. To conclude this article we discuss the implications of our findings, outline the limitations of our study and make recommendations for future research.

Chasing the Anchor: A Systematic Review and Meta-analysis of Perceptual Anchoring Deficits in Developmental Dyslexia

2020 ◽  
Author(s):  
Kurt D Shulver ◽  
Nicholas A Badcock
Keyword(s):  
Systematic Review ◽  
Reading Ability ◽  
English Language ◽  
Prediction Interval ◽  
Meta Analysis ◽  
Visual Assessment ◽  
Individual Performance ◽  
Future Research ◽  
Significant Heterogeneity ◽  
Eligibility Criteria

We report the results of a systematic review and meta-analysis investigating the relationship between perceptual anchoring and dyslexia. Our goal was to assess the direction and degree of effect between perceptual anchoring and reading ability in typical and atypical (dyslexic) readers. We performed a literature search of experiments explicitly assessing perceptual anchoring and reading ability using PsycInfo (Ovid, 1860 to 2020), MEDLINE (Ovid, 1860 to 2019), EMBASE (Ovid, 1883 to 2019), and PubMed for all available years up to June (2020). Our eligibility criteria consisted of English-language articles and, at minimum, one experimental group identified as dyslexic - either by reading assessment at the time, or by previous diagnosis. We assessed for risk of bias using an adapted version of the Newcastle-Ottawa scale. Six studies were included in this review, but only five (n = 280 participants) were included in the meta-analysis (we were unable to access the necessary data for one study).The overall effect was negative, large and statistically significant; g = -0.87, 95% CI [-1.47, 0.27]: a negative effect size indicating less perceptual anchoring in dyslexic versus non-dyslexic groups. Visual assessment of funnel plot and Egger’s test suggest minimal bias but with significant heterogeneity; Q (4) = 9.70, PI (prediction interval) [-2.32, -0.58]. The primary limitation of the current review is the small number of included studies. We discuss methodological limitations, such as limited power, and how future research may redress these concerns. The variability of effect sizes appears consistent with the inherent variability within subtypes of dyslexia. This level of dispersion seems indicative of the how we define cut-off thresholds between typical reading and dyslexia populations, but also the methodological tools we use to investigate individual performance.

Autobiographical Memory Impairments as a Transdiagnostic Feature of Mental Illness: A meta-analysis of autobiographical memory specificity and overgenerality amongst people with psychiatric diagnoses

2020 ◽  
Author(s):  
Tom Joseph Barry ◽  
David John Hallford ◽  
Keisuke Takano
Keyword(s):  
Autobiographical Memory ◽  
Memory Retrieval ◽  
Keyword Search ◽  
Meta Analysis ◽  
Future Research ◽  
Psychiatric Diagnoses ◽  
Schizophrenia Spectrum Disorders ◽  
Memory Impairments ◽  
Memory Specificity ◽  
Causal Mechanisms

Decades of research has examined the difficulty that people with psychiatric diagnoses, such as Major Depressive Disorder, Schizophrenia Spectrum Disorders, and Posttraumatic Stress Disorder, have in recalling specific autobiographical memories from events that lasted less than a day. Instead, they seem to retrieve general events that have occurred many times or which occurred over longer periods of time, termed overgeneral memory. We present the first transdiagnostic meta-analysis of memory specificity/overgenerality, and the first meta-regression of proposed causal mechanisms. A keyword search of Embase, PsycARTICLES and PsycINFO databases yielded 74 studies that compared people with and without psychiatric diagnoses on the retrieval of specific (k = 85) or general memories (k = 56). Multi-level meta-analysis confirmed that people with psychiatric diagnoses typically recall fewer specific (g = -0.864, 95% CI[-1.030, -0.698]) and more general (g = .712, 95% CI[0.524, 0.900]) memories than diagnoses-free people. The size of these effects did not differ between diagnostic groups. There were no consistent moderators; effect sizes were not explained by methodological factors such as cue valence, or demographic variables such as participants’ age. There was also no support for the contribution of underlying processes that are thought to be involved in specific/general memory retrieval (e.g., rumination). Our findings confirm that deficits in autobiographical memory retrieval are a transdiagnostic factor associated with a broad range of psychiatric problems, but future research should explore novel causal mechanisms such as encoding deficits and the social processes involved in memory sharing and rehearsal.

Challenges and Opportunities for Neuroimaging in Young Patients with Traumatic Brain Injury: a Coordinated Effort towards Advancing Discovery from the ENIGMA Pediatric Moderate/Severe TBI Group

2019 ◽  
Author(s):  
Emily L. Dennis ◽  
Karen Caeyenberghs ◽  
Robert F. Asarnow ◽  
Talin Babikian ◽  
Brenda Bartnik-Olson ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Meta Analysis ◽  
Young Patients ◽  
Future Research ◽  
Childhood And Adolescence ◽  
Developmental Issues ◽  
Challenges And Opportunities ◽  
Severe Tbi ◽  
Advance Research

Traumatic brain injury (TBI) is a major cause of death and disability in children in both developed and developing nations. Children and adolescents suffer from TBI at a higher rate than the general population; however, research in this population lags behind research in adults. This may be due, in part, to the smaller number of investigators engaged in research with this population and may also be related to changes in safety laws and clinical practice that have altered length of hospital stays, treatment, and access to this population. Specific developmental issues also warrant attention in studies of children, and the ever-changing context of childhood and adolescence may require larger sample sizes than are commonly available to adequately address remaining questions related to TBI. The ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Pediatric Moderate-Severe TBI (msTBI) group aims to advance research in this area through global collaborative meta-analysis. In this paper we discuss important challenges in pediatric TBI research and opportunities that we believe the ENIGMA Pediatric msTBI group can provide to address them. We conclude with recommendations for future research in this field of study.

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