Cross-Sectional Variation of Intraday Liquidity, Cross-Impact, and Their Effect on Portfolio Execution

Over the past decade, there has been a significant rise in assets managed under passive and systematic strategies. Such strategies hold and trade portfolios in a coordinated manner, often concentrating trading around the end of the trading session. Simultaneously, there has been a rise in activity from market participants that act as liquidity providers, themselves trading along portfolio directions. In “Cross-Sectional Variation of Intraday Liquidity, cross-impact, and Their Effect on Portfolio Execution,” Min, Maglaras, and Moallemi investigate the implications of these two observations, specifically exploring how the phenomenon of portfolio liquidity provision leads to cross-security impact and influences the optimal execution schedules of risk-neutral traders that seek to minimize their expected execution costs. They show that the optimized schedules deviate from the naïve approach that trades each security separately and instead, couple the trading intensity across stocks so as to benefit from the liquidity provided along attractive portfolio trading directions. Empirical analysis demonstrates that coupled optimized schedules could lower costs by as much as 15% relative to the naïve approach.

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Mini-Flash Crashes, Model Risk, and Optimal Execution

Market Microstructure and Liquidity ◽

10.1142/s2382626618500107 ◽

2018 ◽

Vol 04 (01n02) ◽

pp. 1850010 ◽

Cited By ~ 4

Author(s):

Erhan Bayraktar ◽

Alexander Munk

Keyword(s):

Mathematical Model ◽

Trading Volume ◽

Feedback Loops ◽

Model Risk ◽

Human Errors ◽

Partial Synchronization ◽

Market Participants ◽

Liquidity Provision ◽

Optimal Execution ◽

Equilibrium Approach

Oft-cited causes of mini-flash crashes include human errors, endogenous feedback loops and the nature of modern liquidity provision. We develop a mathematical model which captures aspects of these explanations. Empirical features of recent mini-flash crashes are present in our framework. For example, there are periods when no such events will occur. If they do, even just before their onset, market participants may not know with certainty that a disruption will unfold. Our mini-flash crashes can materialize in both low and high trading volume environments and may be accompanied by a partial synchronization in order submission. Instead of adopting a classically-inspired equilibrium approach, we borrow ideas from the optimal execution literature. Each of our agents begins with beliefs about how his own trades impact prices and how prices would move in his absence. They, along with other market participants, then submit orders which are executed at a common venue. Naturally, this leads us to explicitly distinguish between how prices actually evolve and our agents’ opinions. In particular, every agent’s beliefs will be expressly incorrect.

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A technique to prepare cross-sectional TEM specimens of semiconducting devices

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014508x ◽

1986 ◽

Vol 44 ◽

pp. 742-743

Author(s):

A. K. Rai ◽

P. P. Pronko

Keyword(s):

Thin Films ◽

Surface Region ◽

Sample Surface ◽

Specific Region ◽

Cross Sectional ◽

Thin Sections ◽

The Past ◽

Device Structures ◽

Ion Implanted

Several techniques have been reported in the past to prepare cross(x)-sectional TEM specimen. These methods are applicable when the sample surface is uniform. Examples of samples having uniform surfaces are ion implanted samples, thin films deposited on substrates and epilayers grown on substrates. Once device structures are fabricated on the surfaces of appropriate materials these surfaces will no longer remain uniform. For samples with uniform surfaces it does not matter which part of the surface region remains in the thin sections of the x-sectional TEM specimen since it is similar everywhere. However, in order to study a specific region of a device employing x-sectional TEM, one has to make sure that the desired region is thinned. In the present work a simple way to obtain thin sections of desired device region is described.

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Suicidal Ideation Among Medical Students in Dammam, Saudi Arabia

Crisis ◽

10.1027/0227-5910/a000720 ◽

2020 ◽

pp. 1-6

Author(s):

Mohammed Madadin ◽

Ritesh G. Menezes ◽

Maha A. Alassaf ◽

Abdulaziz M. Almulhim ◽

Mahdi S. Abumadini ◽

...

Keyword(s):

Saudi Arabia ◽

Medical Students ◽

Suicidal Ideation ◽

General Health Questionnaire ◽

Cross Sectional Study ◽

Eastern Province ◽

Cross Sectional ◽

The Past ◽

Depression Subscale ◽

History Of

Abstract. Background: Medical students are at high risk of suicidal ideation. Aim: We aimed to obtain information on suicidal ideation among medical students in Dammam located in the Eastern Province of Saudi Arabia. Method: This cross-sectional study was conducted at the College of Medicine affiliated with Imam Abdulrahman Bin Faisal University in the Eastern Province of Saudi Arabia. Suicidal ideation in the past 12 months was assessed based on responses to four questions in the depression subscale of the General Health Questionnaire 28 (GHQ-28). In addition, data were collected to examine the association of suicidal ideation with various factors. Results: We found that 1 in 3 medical students in the study had suicidal ideation in the past 12 months, while around 40% had lifetime suicidal ideation. Suicidal ideation was associated with feelings of parental neglect, history of physical abuse, and dissatisfaction with academic performance. Limitations: The cross-sectional nature of this study limits its ability to determine causality regarding suicidal ideation. Conclusion: These rates are considerably high when compared with rates from studies in other countries around the world. This study provides a reference in the field of suicidology for this region of Saudi Arabia.

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Contributory Factors for Obesity in Elderly: Review of the Literature

10.35262/jiag.v15i3.138-145 ◽

2019 ◽

Vol 15 (3) ◽

Author(s):

Nur Raihan Ismail ◽

Noor Aman Hamid

Keyword(s):

English Language ◽

The Elderly ◽

Dietary Factors ◽

Health Concern ◽

Cross Sectional ◽

Contributory Factors ◽

The Past ◽

Prevalence Of Obesity ◽

Program Intervention ◽

Future Education

Introduction: The prevalence of obesity has been rising, adding to morbidity and mortality. As the proportion of elderly aged 60 years and above grows, so too the prevalence of obesity among this population. Obesity in the elderly is a rapidly growing public health concern as it contributes to significant changes in the health of older people. Objective: This review aims to assess the contributory factors for obesity in the elderly over the past decade. Methods: A literature search was conducted. The search was restricted to articles written in the English language published from 2008 to 2018. Qualitative studies were excluded. Results: A total of 19 full articles were retrieved, of which 18 cross-sectional and one cohort were included. The contributory factors were divided into three components: (a) socio demographic characteristics, (b) medical history and dietary factors and (c) environmental factors. Conclusions: This review informs an emerging knowledge regarding contributory factors for obesity and has implications for future education and program intervention in fighting obesity in the elderly.

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Hepatitis and tuberculosis testing are much less common than HIV testing among adults in Kisumu, Kenya: results from a cross-sectional assessment

BMC Public Health ◽

10.1186/s12889-021-11164-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Joshua Tunnage ◽

Adam Yates ◽

Chiaka Nwoga ◽

Valentine Sing’oei ◽

John Owuoth ◽

...

Keyword(s):

Secondary Education ◽

Viral Hepatitis ◽

Hiv Testing ◽

Spatial Location ◽

Tuberculosis Screening ◽

Cross Sectional ◽

The Past ◽

Prior Testing ◽

Testing Uptake ◽

One Year

Abstract Background Kenya has a high burden of HIV, viral hepatitis, and tuberculosis. Screening is necessary for early diagnosis and treatment, which reduces morbidity and mortality across all three illnesses. We evaluated testing uptake for HIV, viral hepatitis, and tuberculosis in Kisumu, Kenya. Methods Cross-sectional data from adults aged 18–35 years who enrolled in a prospective HIV incidence cohort study from February 2017 to May 2018 were analyzed. A questionnaire was administered to each participant at screening for study eligibility to collect behavioral characteristics and to assess prior testing practices. Among participants without a history of previously-diagnosed HIV, multivariable robust Poisson regression was used to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) for factors potentially associated with HIV testing in the 12 months prior to enrollment. A hierarchical model was used to test for differential access to testing due to spatial location. Results Of 671 participants, 52 (7.7%) were living with HIV, 308 (45.9%) were female, and the median age was 24 (interquartile range 21–28) years. Among 651 (97.0%) who had ever been tested for HIV, 400 (61.2%) reported HIV testing in the past 6 months, 129 (19.7%) in the past 6–12 months, and 125 (19.1%) more than one year prior to enrollment. Any prior testing for viral hepatitis was reported by 8 (1.2%) participants and for tuberculosis by 51 (7.6%). In unadjusted models, HIV testing in the past year was more common among females (PR 1.08 [95% CI 1.01, 1.17]) and participants with secondary education or higher (PR 1.10 [95% CI 1.02, 1.19]). In the multivariable model, only secondary education or higher was associated with recent HIV testing (adjusted PR 1.10 [95% CI 1.02, 1.20]). Hierarchical models showed no geographic differences in HIV testing across Kisumu subcounties. Conclusions Prior HIV testing was common among study participants and most had been tested within the past year but testing for tuberculosis and viral hepatitis was far less common. HIV testing gaps exist for males and those with lower levels of education. HIV testing infrastructure could be leveraged to increase access to testing for other endemic infectious diseases.

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Ten-year trends of hypertension treatment and control rate in Korea

Scientific Reports ◽

10.1038/s41598-021-86199-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kwang-il Kim ◽

Eunjeong Ji ◽

Jung-yeon Choi ◽

Sun-wook Kim ◽

Soyeon Ahn ◽

...

Keyword(s):

Age Groups ◽

Favorable Effect ◽

Age Group ◽

Hypertension Treatment ◽

Treatment Rate ◽

Cross Sectional ◽

The Past ◽

Nationally Representative ◽

Multistage Sampling ◽

And Control

AbstractWe analyzed the Korean National Health and Nutrition Examination Survey (KNHANES) database to determine the trends of hypertension treatment and control rate in Korea over the past 10 years. In addition, we tried to investigate the effect of chronic medical conditions on hypertension management. We investigated the hypertension prevalence, awareness, treatment, and control rate from 2008 to 2017. KNHANES, which uses a stratified multistage sampling design, is a cross-sectional, nationally representative survey conducted by the Korean government. A total of 59,282 adults (≥ 20 years) were included, which was representative of the total population of around 40 million Koreans per year. The mean age was 50.7 ± 16.4 years and 42.6% were male. The prevalence of hypertension, hypercholesterolemia, diabetes mellitus, and obesity significantly increased over the 10 years. During this period, the hypertension treatment and control rate significantly improved. Hypertension treatment rate was significantly lower in the younger age group compared to the older age group, but the control rate among the treated patients was not significantly different between age groups. The treatment and control rates of hypertension were higher in patients with multimorbidity, which implies that it has a favorable effect on the treatment and control of hypertension. Hypertension treatment and control rate have improved over the past 10 years. The higher treatment and control rate in patients with multimorbidity suggest that the more aggressive surveillance might be associated with the improvement of hypertension treatment and control rate in Korea.

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Essential newborn care practice and its associated factors in Southwest Ethiopia

Archives of Public Health ◽

10.1186/s13690-021-00568-6 ◽

2021 ◽

Vol 79 (1) ◽

Author(s):

Haimanot Abebe ◽

Daniel Adane ◽

Solomon Shitu

Keyword(s):

Associated Factors ◽

Newborn Care ◽

Care Practice ◽

Framework Analysis ◽

Cross Sectional ◽

Essential Newborn Care ◽

Southwest Ethiopia ◽

The Past ◽

Newborn Care Practice ◽

Pregnant Mothers

Abstract Background Essential newborn care is a wide-ranging strategy intended to improve the health of newborns by implementing appropriate interventions. Approximately in 2018, an estimated 2.5 million children died in their first month of life, which is approximately 7000, newborns every day, with about a third of all neonatal deaths occurring within the first day after birth. Even though the most cause of death is preventable the burden of neonatal death is a still high in developing countries including Ethiopia. Therefore this study is aimed to assess the level of essential newborn care practice among mothers who gave birth within the past six months in Gurage Zone, Southwest Ethiopia. Methods A community-based cross-sectional study was conducted among mothers who gave birth within the past six months in Gurage Zone, Southwest Ethiopia. For the quantitative part, 624 study participants were involved by using a multi-stage sampling method. A systematic random sampling technique was to reach the study subjects. Data entry was carried out by Epi data version 4.0.0 and analysis was done by SPSS window version 24. Binary and multivariate logistic regressions were used to identify associated factors. For the qualitative part, three focus group discussions (FGD) with purposively selected 30 mothers were involved. The data were analyzed deductively by using the thematic framework analysis approach by using Open code version 4.02. Result Overall good essential newborn care practice was found to be 41.0% [95%CI, 36.6–44.7]. Being urban residence [AOR 1.70, 95%CI: 1.03–2.79], attending antenatal care visit [AOR = 3.53, 95%CI: 2.14–5.83], attending pregnant mothers meeting [AOR = 1.86, 95%CI: 1.21–2.86], had immediate postnatal care [AOR = 3.92, 95% CI: 2.65–5.78], and having good knowledge about ENC [AOR = 2.13, 95% CI: 1.47–3.10] were significantly associated with good essential newborn care practice. Conclusion This study indicated that the magnitude of essential newborn care practice was low. Thus, a primary health care provider should regularly provide ENC for newborns and take opportunities to counsel the mothers about ENC during pregnant mothers meeting and MCH services sessions.

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Knowledge and perceptions of cardiopulmonary resuscitation amongst New Zealand podiatrists: a web-based survey

Journal of Foot and Ankle Research ◽

10.1186/s13047-021-00481-9 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Angela Brenton-Rule ◽

Daniel Harvey ◽

Kevin Moran ◽

Daniel O’Brien ◽

Jonathon Webber

Keyword(s):

New Zealand ◽

Cardiopulmonary Resuscitation ◽

Life Support ◽

Survival Rates ◽

Sudden Cardiac Arrest ◽

Cross Sectional Study ◽

Trial Registration ◽

Cross Sectional ◽

Web Based ◽

The Past

Abstract Background Podiatrists in New Zealand have a duty of care to assist patients in an emergency, and current cardiopulmonary resuscitation (CPR) certification is a requirement for registration. However, it is unknown how competent and confident podiatrists are in administering CPR and how they would respond in an emergency. Having a health professional who has a competent knowledge of CPR and skills in basic life support, can improve survival rates from sudden cardiac arrest. Therefore, the aim of this study was to survey New Zealand podiatrists to determine their CPR knowledge and qualifications; beliefs about the application of CPR; and perceptions of their competency in CPR. Methods This cross-sectional study used a web-based survey. Participants were New Zealand registered podiatrists with a current annual practising certificate. The 31-item survey included questions to elicit demographic information, CPR practice and attitudes, and CPR knowledge. Responses were collected between March and August 2020. Results 171 podiatrists responded to the survey. 16 % of the podiatrists (n = 28) had performed CPR in an emergency, with a 50 % success rate. Participants were predominantly female (n = 127, 74 %) and working in private practice (n = 140,82 %). Nearly half of respondents were younger than 40 years (n = 75,44 %) and had less than 10 years of clinical experience (n = 73, 43 %). Nearly all (n = 169,97 %) participants had received formal CPR training in the past two years, with 60 % (n = 105) receiving training in the past 12 months. Most respondents (n = 167,98 %) self-estimated their CPR ability as being effective, very effective, or extremely effective. Participants’ knowledge of CPR was variable, with the percentage of correct answers for CPR protocol statements ranging between 20 and 90 %. Conclusions This study provides the first insight into New Zealand podiatrists’ CPR knowledge and perceptions. Podiatrists were found to have high levels of CPR confidence but demonstrated gaps in CPR knowledge. Currently, New Zealand registered podiatrists require biennial CPR re-certification. However, resuscitation authorities in New Zealand and overseas recommend an annual update of CPR skills. Based on this study’s findings, and in line with Australia and the United Kingdom, the authors recommend a change from biennial to annual CPR re-certification for podiatrists in New Zealand. Trial registration The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12620001144909).

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Nicotine dependence of cigarette and heated tobacco users in Japan, 2019: a cross-sectional analysis of the JASTIS Study

Tobacco Control ◽

10.1136/tobaccocontrol-2020-056237 ◽

2021 ◽

pp. tobaccocontrol-2020-056237

Author(s):

Yan Kwan Lau ◽

Sumiyo Okawa ◽

Rafael Meza ◽

Kota Katanoda ◽

Takahiro Tabuchi

Keyword(s):

Nicotine Dependence ◽

Tobacco Use ◽

Cross Sectional ◽

The Public ◽

The Past ◽

Cross Sectional Analysis ◽

Binomial Regression ◽

Sectional Analysis ◽

Prevalence Ratios ◽

Min Cut

ObjectivesJapan is currently the biggest market of heated tobacco products (HTPs) in the world. Little is known about nicotine dependence among HTP users. Thus, the objective was to assess the association of type of tobacco use and time-to-first-use, a marker of nicotine dependence.MethodsA cross-sectional analysis of the 2019 data from an internet cohort study was conducted. The analytical sample consisted of 2147 current (≥1 day use in the past 30 days) HTP and/or conventional cigarette users, aged 25+ years. Marginal structural binomial regression was used to estimate nicotine dependence prevalence ratios (PRs) for each category of tobacco use (exclusive daily cigarette, exclusive HTP (≥1 day), dual HTP+daily cigarette, dual HTP+non-daily cigarette), relative to exclusive, non-daily cigarette smoking.ResultsUsing a 5 min cut-off for time-to-first-use, the prevalence of nicotine dependence was higher among dual users of HTP and daily cigarettes (PR=1.38; 95% CI: 1.05 to 1.82) and exclusive, daily cigarette users (PR=1.48; 95% CI: 1.15 to 1.91), relative to exclusive, non-daily cigarette users. However, nicotine dependence among exclusive HTP users, and dual HTP+non-daily cigarette users, did not differ from that of exclusive, non-daily cigarette users. When using 15 and 30 min cut-offs, all types of users, including exclusive HTP, had higher levels of nicotine dependence relative to exclusive, non-daily cigarette users.ConclusionsRegardless of HTP use, daily cigarette users had higher prevalence of nicotine dependence compared with non-daily cigarette users. Exclusive HTP users had similar (or potentially higher) dependence compared with exclusive, non-daily cigarette users. Longitudinal studies are needed to interrogate the public health implications of growing HTP use worldwide.

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106 Self-Reported Sleep and Resilience

SLEEP ◽

10.1093/sleep/zsab072.105 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A43-A44

Author(s):

Michelle Persich ◽

Sara Cloonan ◽

Michael Grandner ◽

William Killgore

Keyword(s):

Sleep Quality ◽

Sleep Time ◽

Self Report ◽

Subjective Perception ◽

Psychological Resilience ◽

Cross Sectional ◽

Sleep Quantity ◽

The Past ◽

Resilience Scale ◽

Longitudinal Effects

Abstract Introduction Psychological resilience is the ability to withstand setbacks, adapt positively to challenges, and bounce back from the adversities of life. While the construct of resilience is broadly understood, the specific individual factors that contribute to the ability to be resilient and persevere in the face of difficulties remain poorly understood. We recently showed that psychological resilience during the COVID-19 pandemic was associated with a number of factors, including fewer complaints of insomnia, and others have suggested that sleep is an important contributor. We therefore tested the hypothesis that sleep quality and acute sleep quantity would combine to predict measures of psychological resilience and perseverance (i.e. “grit”). Methods We asked 447 adults (18–40 yrs; 72% female) to report the number of hours of sleep obtained the night before their assessment session (SLEEP), and complete several questionnaires, including the Pittsburgh Sleep Quality Index (PSQI), the Connor-Davidson Resilience Scale (CD-RISC), Bartone Dispositional Resilience Scale (Hardiness), and the Grit Scale. Sleep metrics were used to predict resilience, hardiness, and grit using multiple linear regression. Results For resilience, PSQI (β=-.201, p<.00003) and SLEEP (β=.155, p<.001) each contributed uniquely to prediction of CD-RISC (R2=.08, p<.00001). Hardiness was also predicted (R2=.08, p<.00001) by a combination of PSQI (β=-.218, p<.00001) and SLEEP (β=.128, p=.007). Interestingly, worse sleep quality over the past month on the PSQI (β=.13, p=.008) in combination with more SLEEP the night before the assessment (β=.137, p=.005) each contributed uniquely to higher Grit (i.e., perseverance; R2=.03, p=.003). Conclusion Self-reported sleep quality and quantity were both independently associated with greater self-reported resilience, hardiness, and grit. While better sleep quality and more sleep the night before testing each uniquely predicted greater resilience and hardiness, a different pattern emerged for Grit. The combination of lower quality sleep over the past month followed by greater recent sleep duration was associated with increased perseverance. Whereas sleep quality appears to be more important for general resilience/hardiness, recent sleep time appears more important for the subjective perception of perseverance. Because these data are purely self-report and cross sectional, future work will need to determine the longitudinal effects on behavior. Support (if any):

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