A Comparative Analysis of the Determinants and Pricing of Liquidity in Floor and Electronic Trading Systems

In recent years many stock exchanges have moved away from floor-based to automated-based trading systems. However, the choice between these alternative trading systems is a major concern for stock exchange regulators and designers, and the impact of their merits on market characteristics (e.g. liquidity) is controversial. This thesis is motivated by the desire to shed light on this controversy, and therefore aims to offer a comparative analysis of various aspects of liquidity under floor and automated trading systems. More specifically, within the context of different trading systems (i.e. floor versus electronic), this thesis examines three empirical issues: firstly, the determinants of market-wide liquidity and its time-series behaviour; secondly, whether market-wide and firm-specific liquidity are priced in assets returns; and finally, whether the cross-sectional variations in firm-specific liquidity could be explained by the cross-sectional variations in information asymmetry and divergence of opinion. The findings of this thesis can be summarized as follows. Firstly, market-wide liquidity is significantly influenced by market returns, market volatility, interest rate variables and the announcement of macroeconomic indicators. Market-wide liquidity also shows distinct day-of-the-week regularities and a distinct pattern around holidays. The impact of some factors on market-wide liquidity, and the time-series behaviour of market-wide liquidity on the floor trading system in some markets is higher than that on the electronic trading systems. Secondly, market-wide liquidity has a significant impact on assets returns, and after controlling for its effect, firm-specific liquidity has a significant effect on risk-adjusted returns. The liquidity premium required on market-wide and firm-specific liquidity, for some proxies of liquidity in some markets, is higher on an automated trading system than on a floor trading system. Finally, firm-specific liquidity is negatively related to the level of information asymmetry. However, the evidence for the impact of divergence of opinion on firm-specific liquidity is inconclusive; a higher level of divergence of opinion results in higher liquidity, which supports the optimistic view; and firm-specific liquidity decreases with divergence of opinion, which is consistent with the view that disagreement among investors is a source of risk. Additionally, after automation, the impact of information asymmetry (divergence of opinion) on firm-specific liquidity is greater (lesser) than that before automation. Overall, this thesis demonstrates that the design and the structure of markets is closely linked to the latter’s performance and that the change to automated trading systems has significant implications for liquidity. As such, this study should be a valuable reference point for stock exchanges that have introduced automation, or are considering doing so

Commonality in Liquidity in the Context of Different Trading Systems: Evidence from an Emerging Market

We offer hitherto unpublished evidence of the impact of different trading systems on commonality in liquidity from an emerging market i.e. The Amman Stock Exchange. We argue that the degree of responsiveness of individual stock's liquidity to changes in market-wide liquidity will vary before and after the automation of a trading system, due to the differences in market structure. In general, the results show different sensitivities in the stock liquidity to changes in market-wide liquidity on both trading systems; the mean coefficient of concurrent market-wide liquidity on an electronic trading system is larger than that on a floor trading system. We also provide evidence on the existence of size effect in commonality. However, regardless of the size pattern revealed in commonality, the liquidity of firms in electronic trading system shows a stronger response to changes in market-wide liquidity. Finally, the results show the existence of commonality within the same industry, which is also stronger after the automation of a trading system. The above results imply that the floor trading system is less vulnerable to the information asymmetry problem.   Keywords: Liquidity, commonality, market microstructure, information asymmetry, floor trading system, electronic trading systems. JEL Classifications: D47; D82; G10; G1

Ownership structure and agency costs: evidence from the insurance industry in Jordan

Purpose: This study investigated the impact of corporate ownership structure on agency costs in the insurance industry. Design/methodology/approach: The study sample included 23 insurance companies listed on the Amman Stock Exchange (ASE) from 2010 to 2019. Panel regression was used to account for the firm- and time-specific unobservable variables and system-GMM estimation was used to address endogeneity concerns. Findings: The results show that managerial ownership positively (negatively) affects selling, general and administrative (SG&A) expenses (assets turnover), implying that unmonitored managers engage in activities that serve their own interests rather than those of shareholders. The largest shareholder's ownership has no impact on agency costs, implying that the ownership of the largest shareholder is irrelevant. However, as the wedge between the percentage of capital owned by the largest shareholders and managers increases, SG&A expenses (efficiency ratio) decrease (increases), indicating that the existence of large non-management shareholders reduces agency costs. After accounting for the endogeneity problem, the impact of ownership structure on agency costs measured by asset turnover remains robust. Originality/value: To the best of the authors' knowledge, this study is the first to provide unique evidence and useful insights into the determinants of agency costs from a frontier market in the Middle East and North Africa (MENA), with a focus on the insurance sector. Additionally, this study uses a new measure of separation between ownership and control by calculating the wedge between managers' and large shareholders' ownership

A review of the role of glass waste on the fresh and mechanical properties of concrete as an environmentally friendly materials

One of the biggest problems facing the world is the management of waste glass. This waste glass can come from glass containers or packaging, flat glass, household or tableware glass, or continuous filament glass. The problem is becoming increasingly difficult as more and more waste glass is generated and landfill space is becoming constrained. One potential method to solving this issue is to convert glass waste into construction substances. The use of recycled waste glass in the production of cementitious concretes as environmentally friendly building materials has recently attracted considerable interest in the construction sector. Therefore, studies aim to recycle glass waste into concrete, which is a great opportunity to produce cement mortar and concrete. Even though a significant amount of glass waste is generated worldwide every year, only a small portion of it is reused by mixing it into concrete, which is an efficient way to address the problem. This study provides a critical review of the work done on the reuse of glass waste as a substitute for cement and aggregates in terms of the mechanical and fresh properties of mortar and concrete production. In addition, this research intends to provide a clearer knowledge of the incorporation of reused glass waste glass as an environmentally friendly resource in the concrete industry. It also aims to establish future research objectives and promote the utilization of concrete made from recyclable materials in the development of environmentally friendly and durable concrete. This study shows that incorporating glass waste into concrete improves its properties. It was also found that the properties of concrete compared to conventional concrete and mortar mainly depend on various factors such as shape, type, size and replacement ratio

Factors and issues affecting electronic insurance adoption in an emerging market

This study examines the factors and issues affecting the adoption of electronic insurance (EI) in the Jordanian insurance sector. The methodology of the study is based on convenience sampling, thus, the sample consists of 175 respondents familiar with E-services, with different backgrounds, professions, businesses, income groups, sectors, and regions. Questionnaires were distributed and disseminated electronically using SurveyMonkey. The study employs both descriptive and ANOVA analyses to analyze the responses. The results show that EI promotes sustainability, reduces costs, saves time and holds some operational benefits beneath. The ANOVA results show that the impact of income and age on sustainability, cost-effectiveness, and operational benefits is significant at least at the 5% significance level. Respondents are also aware that EI may involve issues and challenges related to security and privacy, customer-related issues such as lack of knowledge about repositories, and insurer-related issues such as data shifting. The ANOVA results indicate that gender affects customers’ perceptions of EI adoption regarding customer-related issues; its effect is significant at the 5% level of significance. On the other hand, age and income level are important factors that shape respondents’ perceptions of EI in Jordan. Age is only significant for security-related issues, and income level is a deciding factor in insurer-related issues; their effect is strong and highly significant at the 5% and 1% levels, respectively

The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy

Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations. Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves. Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p  90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score. Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research