Twitter’s Relationship with Overreaction in Individual Security Returns

Using stock market return data from 2007 to 2019 from The Center for Research in Security Prices, I inquire into the impact that Twitter has on the overreactions of individual stock returns by breaking down returns into pre and post-Twitter periods. I examine negative serial correlation, demonstrating return reversals, between a lag crossed Twitter dummy variable and initial returns. With stock reversals serving as an indicator of initial overreaction and assuming stationarity of overreactions over time, I find that the presence of Twitter results in significantly more overreactions for highly followed companies when using monthly returns. However, when assessing Twitter’s influence using weekly returns, the results suggest the possibility of return momentum. Similarly, Twitter’s influence on overreaction is a highlighted when evaluating only negatively or positively large returns, producing greater significance despite a decrease sample size. While these promising results are not economically significant and thus do not reveal a viable contrarian investment strategy, my paper lays the foundation for a predictive model based of Twitter’s influence on company returns

As newly returned New York Police Commissioner, Bill Bratton’s first task will be to regain the trust of the city’s most heavily policed groups

Last week, Bill Bratton was sworn in as New York City’s police commissioner, as part of the administration of new mayor, Bill de Blasio. David Halle, Andrew A. Beveridge, and Sydney Beveridge, take a closer look at Bill Bratton’s policy success in reducing crime, in both New York and Los Angeles, through the use of the COMPSTAT program and its successors. They write that, now that he has returned to New York, Bratton’s challenge will be to keep crime rates low while reducing the widespread hatred of the police among black residents that has been created by ‘Stop & Frisk’ policies

Beyond Rio+20: governance for a green economy

This repository item contains a single issue of the Pardee Center Task Force Reports, a publication series that began publishing in 2009 by the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future.As an intellectual contribution to the preparations for the 2012 United Nations Conference on Sustainable Development (UNCSD, a.k.a. Rio +20), the Boston University Frederick S. Pardee Center for the Study of the Longer-Range Future convened a task force of experts to discuss the role of institutions in the actualization of a green economy in the context of sustainable development. A stellar group of experts from academia, government and civil society convened at the Pardee Center and were asked to outline ideas about what the world has learned about institutions for sustainable development from the past, and what we can propose about the governance challenges and opportunities for the continuous development of a green economy in the future. The Task Force members were encouraged to think big and think bold. They were asked to be innovative in their ideas, and maybe even a little irreverent and provocative. They were charged specifically NOT to come to consensus about specific recommendations, but to present a variety and diversity of views. This report presents their thoughts and ideas

Using mixed methods for analysing culture : The Cultural Capital and Social Exclusion project

This paper discusses the use of material generated in a mixed method investigation into cultural tastes and practices, conducted in Britain from 2003 to 2006, which employed a survey, focus groups and household interviews. The study analysed the patterning of cultural life across a number of fields, enhancing the empirical and methodological template provided by Bourdieu’s Distinction. Here we discuss criticisms of Bourdieu emerging from subsequent studies of class, culture and taste, outline the arguments related to the use of mixed methods and present illustrative results from the analysis of these different types of data. We discuss how the combination of quantitative and qualitative methods informed our analysis of cultural life in contemporary Britain. No single method was able to shed light on all aspects of our inquiry, lending support to the view that mixing methods is the most productive strategy for the investigation of complex social phenomena

Cardiovascular risk in high-hazard occupations: the role of occupational cardiology

Abstract Work is beneficial for health, but many individuals develop cardiovascular disease (CVD) during their working lives. Occupational cardiology is an emerging field that combines traditional cardiology sub-specialisms with prevention and risk management unique to specific employment characteristics and conditions. In some occupational settings incapacitation through CVD has the potential to be catastrophic due to the nature of work and/or the working environment. These are often termed 'hazardous' or 'high-hazard' occupations. Consequently, many organizations that employ individuals in high-hazard roles undertake pre-employment medicals and periodic medical examinations to screen for CVD. The identification of CVD that exceeds predefined employer (or regulatory body) risk thresholds can result in occupational restriction, or disqualification, which may be temporary or permanent. This article will review the evidence related to occupational cardiology for several high-hazard occupations related to aviation and space, diving, high altitude, emergency workers, commercial transportation, and the military. The article will focus on environmental risk, screening, surveillance, and risk management for the prevention of events precipitated by CVD. Occupational cardiology is a challenging field that requires a broad understanding of general cardiology, environmental, and occupational medicine principles. There is a current lack of consensus and contemporary evidence which requires further research. Provision of evidence-based, but individualized, risk stratification and treatment plans is required from specialists that understand the complex interaction between work and the cardiovascular system. There is a current lack of consensus and contemporary evidence in occupational cardiology and further research is required

Assessing the practicality of ARK identifier usage in a catalogue of medieval manuscripts

In data management, the use of identifiers is essential for disambiguation and referencing. The scope of the use of identifiers varies. For example, disambiguation within an institution using integer identifiers may be sufficient for operational procedures, whereas digital scholarship using global resources relies on universally unique identifiers. In this paper we investigate practical routes to globally unique identifiers for the medieval manuscripts of the Bodleian Library. The Oxford Linked Open Data (OxLOD) and Mapping Manuscript Migrations (MMM) projects require unique identifiers for the transformation of the medieval manuscripts catalogue into linked data, in an effort to increase discoverability and consistency across platforms. We consider how Archival Resource Keys (ARKs), a type of URI, can be applied to the Medieval Manuscript catalog as well as determining how ARKs can support MMM's research goals. We begin with examining the Text Encoding Initiative (TEI) catalogue records to under-stand the data provided and identify and describe entities which do not presently have identifiers. Further, we evaluate ARKs for producing identifiers, prioritizing those which are required to answer common research questions

Interobserver agreement and prognostic impact for MRI–based 2018 FIGO staging parameters in uterine cervical cancer

Objectives To evaluate the interobserver agreement for MRI–based 2018 International Federation of Gynecology and Obstetrics (FIGO) staging parameters in patients with cervical cancer and assess the prognostic value of these MRI parameters in relation to other clinicopathological markers. Methods This retrospective study included 416 women with histologically confirmed cervical cancer who underwent pretreatment pelvic MRI from May 2002 to December 2017. Three radiologists independently recorded MRI–derived staging parameters incorporated in the 2018 FIGO staging system. Kappa coefficients (κ) for interobserver agreement were calculated. The predictive and prognostic values of the MRI parameters were explored using ROC analyses and Kaplan–Meier with log-rank tests, and analyzed in relation to clinicopathological patient characteristics. Results Overall agreement was substantial for the staging parameters: tumor size > 2 cm (κ = 0.80), tumor size > 4 cm (κ = 0.76), tumor size categories (≤ 2 cm; > 2 and ≤ 4 cm; > 4 cm) (κ = 0.78), parametrial invasion (κ = 0.63), vaginal invasion (κ = 0.61), and enlarged lymph nodes (κ = 0.63). Higher MRI–derived tumor size category (≤ 2 cm; > 2 and ≤ 4 cm; > 4 cm) was associated with a stepwise reduction in survival (p ≤ 0.001 for all). Tumor size > 4 cm and parametrial invasion at MRI were associated with aggressive clinicopathological features, and the incorporation of these MRI–based staging parameters improved risk stratification when compared to corresponding clinical assessments alone. Conclusion The interobserver agreement for central MRI–derived 2018 FIGO staging parameters was substantial. MRI improved the identification of patients with aggressive clinicopathological features and poor survival, demonstrating the potential impact of MRI enabling better prognostication and treatment tailoring in cervical cancer.publishedVersio

What MRI-based tumor size measurement is best for predicting long-term survival in uterine cervical cancer?

Background: Tumor size assessment by MRI is central for staging uterine cervical cancer. However, the optimal role of MRI-derived tumor measurements for prognostication is still unclear. Material and methods: This retrospective cohort study included 416 women (median age: 43 years) diagnosed with cervical cancer during 2002–2017 who underwent pretreatment pelvic MRI. The MRIs were independently read by three radiologists, measuring maximum tumor diameters in three orthogonal planes and maximum diameter irrespective of plane (MAXimaging). Inter-reader agreement for tumor size measurements was assessed by intraclass correlation coefficients (ICCs). Size was analyzed in relation to age, International Federation of Gynecology and Obstetrics (FIGO) (2018) stage, histopathological markers, and disease-specific survival using Kaplan–Meier-, Cox regression-, and time-dependent receiver operating characteristics (tdROC) analyses. Results: All MRI tumor size variables (cm) yielded high areas under the tdROC curves (AUCs) for predicting survival (AUC 0.81–0.84) at 5 years after diagnosis and predicted outcome (hazard ratios [HRs] of 1.42–1.76, p < 0.001 for all). Only MAXimaging independently predicted survival (HR = 1.51, p = 0.03) in the model including all size variables. The optimal cutoff for maximum tumor diameter (≥ 4.0 cm) yielded sensitivity (specificity) of 83% (73%) for predicting disease-specific death after 5 years. Inter-reader agreement for MRI-based primary tumor size measurements was excellent, with ICCs of 0.83–0.85. Conclusion: Among all MRI-derived tumor size measurements, MAXimaging was the only independent predictor of survival. MAXimaging ≥ 4.0 cm represents the optimal cutoff for predicting long-term disease-specific survival in cervical cancer. Inter-reader agreement for MRI-based tumor size measurements was excellent.publishedVersio

A 16-week comparison of the novel insulin analog insulin glargine (HOE 901) and NPH human insulin used with insulin lispro in patients with type 1 diabetes

WSTĘP. Ocena bezpieczeństwa i skuteczności glarginy, długodziałającego analogu insuliny ludzkiej, jako składnika insulinoterapii opartej na wielokrotnych wstrzyknięciach u chorych na cukrzycę typu 1. MATERIAŁ I METODY. Chorych na cukrzycę typu 1 leczonych wielokrotnymi wstrzyknięciami insuliny (ludzka insulina NPH oraz bolusy insuliny lispro) randomizowano do grupy leczonej glarginą (HOE 901), długodziałającym analogiem insuliny, podawaną raz dziennie (n = 310) albo do grupy leczonej insuliną NPH (n = 309) jako insuliną podstawową i kontynuowano podawanie bolusów insuliny lispro. Badanie trwało 16 tygodni i było badaniem otwartym. Chorzy otrzymywali insulinę NPH według dotychczasowego schematu, to znaczy 1 lub 2 razy dziennie, natomiast chorzy randomizowani do grupy leczonej glarginą otrzymywali ją raz dziennie wieczorem. WYNIKI. U chorych otrzymujących glarginę glikemia na czczo według pomiarów domowych była znamiennie niższa niż u wszystkich osób leczonych insuliną NPH (średnio: &#8211;42,0 &plusmn; 4,7 i &#8211;12,4 &plusmn; 4,7 mg/dl [&#8211;2,33 &plusmn; 0,26 i &#8211;0,69 &plusmn; 0,26 mmol/l]; p = 0,0001). Te różnice pojawiały się dość wcześnie i utrzymywały się do końca badania. Założoną glikemię 119 mg/dl (< 6,6 mmol/l) uzyskało więcej chorych leczonych glarginą (29,6%) niż insuliną NPH (16,8%). Nie stwierdzono jednak różnic dotyczących stężenia hemoglobiny glikowanej. Leczenie glarginą wiązało się również z wyraźnie mniejszymi wahaniami glikemii na czczo (p = 0,0124). Nie obserwowano różnic w częstości objawowej hipoglikemii, także nocnej. Również objawy niepożądane były podobne w obu grupach, z wyjątkiem większej bolesności w miejscu wstrzyknięcia w grupie chorych otrzymujących glarginę (6,1 vs 0,3% dla osób otrzymujących insulinę NPH). Masa ciała zwiększyła się o 0,12 kg u pacjentów leczonych glarginą i o 0,54 kg u pacjentów leczonych insuliną NPH (p = 0,034). WNIOSKI. Stosowanie glarginy raz dziennie jako insuliny podstawowej wydaje się leczeniem bezpiecznym i co najmniej tak samo efektywnym jak leczenie insuliną NPH stosowaną 1 lub 2 razy dziennie u chorych na cukrzycę typu 1 leczonych bolusami insuliny lispro.OBJECTIVE. To determine the safety and efficacy of the long-acting insulin analog, insulin glargine, as a component of basal bolus therapy in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS. Patients with type 1 diabetes receiving basal-bolus insulin treatment with NPH human insulin and insulin lispro were randomized to receive insulin glargine (HOE 901), a long-acting basal insulin analog, once a day (n = 310) or NPH human insulin (n = 309) as basal treatment with continued bolus insulin lispro for 16 weeks in an open-label study. NPH insulin patients maintained their prior schedule of administration once or twice a day, whereas insulin glargine patients received basal insulin once a day at bedtime. RESULTS. Compared with all NPH insulin patients, insulin glargine patients had significant decreases in fasting blood glucose measured at home (means &#177; SEM, 42.0&#177; &#177; 4.7 vs. 12.4 &#177; 4.7 mg/dl [&#150;2.33 &#177; 0.26 vs. 0.69 &#177; 0.26 mmol/l]; P = 0.0001). These differences were evident early and persisted throughout the study. More patients in the insulin glargine group (29.6%) than in the NPH group (16.8%) reached a target fasting blood glucose of 119 mg/dl (6.6 mmol/l). However, there were no differences between the groups with respect to change in GHb. Insulin glargine treatment was also associated with a significant decrease in the variability of fasting blood glucose values (P = 0.0124). No differences in the occurrence of symptomatic hypoglycemia, including nocturnal hypoglycemia, were observed. Overall, adverse events were similar in the two treatment groups with the exception of injection site pain, which was more common in the insulin glargine group (6.1%) than in the NPH group (0.3%). Weight gain was 0.12 kg in insulin glargine patients and 0.54 kg in NPH insulin patients (P = 0.034). CONCLUSIONS. Basal insulin therapy with insulin glargine once a day appears to be as safe and at least as effective as using NPH insulin once or twice a day in maintaining glycemic control in patients with type 1 diabetes receiving basal-bolus insulin treatment with insulin lispro

Linguistics

Contains table of contents for Section 4, an introduction and abstracts of eight doctoral dissertations