186 research outputs found
Investment Risk and Returns: The Relationship Between A Stock and An Index Using the Modern Portfolio Theory
The aim of this report is to examine investment risk and returns by looking at the relationship between a stock and an index using the Markowitz Modern Portfolio theory. Monthly Data on IBM and Dow Jones were obtained from yahoo finance for the period 1995 to 2015. A linear regression was utilized to analyze the relationship between the Dow Jones index and the IBM stock returns. The results revealed that there is a positive relationship between IBM stock returns and the Dow Jones index. In their decision making, investors and policy makers are, recommended to additionally consider the micro and macro demand and supply forces that could possibly influence ROI. In other to avoid or reduce risk. Keywords: Portfolio, investment, risk, index, relationship, stock
Optimum hybrid error correction scheme under strict delay constraints
In packet-based wireless networks, media-based services often require a multicast-enabled transport that guarantees quasi error free transmission under strict delay constraints. Furthermore, both multicast and delay constraints deeply influence the architecture of erasure error recovery (EER). Therefore, we propose a general architecture of EER and study its optimization in this thesis. The architecture integrates overall existing important EER techniques: Automatic Repeat Request, Forward Error Correction and Hybrid ARQ techniques. Each of these EER techniques can be viewed as a special case of Hybrid Error Correction (HEC) schemes. Since the Gilbert-Elliott (GE) erasure error model has been proven to be valid for a wide range of packet based wireless networks, in this thesis, we present the general architecture and its optimization based on the GE channel model. The optimization target is to satisfy a certain target packet loss level under strict delay constraints efficiently. Through the optimization for a given real-time multicast scenario, the total needed redundancy information can be minimized by choosing the best HEC scheme automatically among the entire schemes included in the architecture. As a result, the performance of the optimum HEC scheme can approach the Shannon limit as closely as possible dynamically according to current channel state information.In Paket-basierten drahtlosen Netzwerken benötigen Medien-basierte Dienste oft Multicast-fähigen Transport, der quasi-fehlerfreie Übertragung unter strikten Zeitgrenzen garantiert. Außerdem beeinflussen sowohl Multicast als auch Zeitbegrenzungen stark die Architektur von Auslöschungs-Fehlerschutz (Erasure Error Recovery, EER). Daher stellen wir eine allgemeine Architektur der EER vor und untersuchen ihre Optimierung in dieser Arbeit. Die Architektur integriert alle wichtigen EER-Techniken: Automatic Repeat Request, Forward Error Correction und Hybrid ARQ. Jede dieser EER-Techniken kann als Spezialfall der Hybrid Error Correction (HEC) angesehen werden. Da das Gilbert-Elliot (GE) Auslöschungs-Fehler-Modell für einen weiten Bereich von Paket-basierten drahtlosen Netzwerken als gültig erwiesen wurde, präsentieren wir in dieser Arbeit die allgemeine Architektur und deren Optimierung basierend auf dem GE Kanalmodell. Zweck der Optimierung ist es, eine gewisse Ziel-Paketfehlerrate unter strikten Zeitgrenzen effizient zu erreichen. Durch die Optimierung für ein gegebenes Echtzeit-Mutlicast-Szenario kann die insgesamt benötigte Redundanz-Information minimiert werden. Dies erfolgt durch automatische Auswahl des optimalen HEC Schemas unter all den Schemata, die in die Architektur integriert sind. Das optimale HEC-Schema kann die Shannon Grenze so nahe wie möglich, dynamisch, entsprechend dem derzeitigen Kanalzustand, erreichen
Impact of Basel Iii Regulations on Banks: Evidence from Afriland First Bank in Cameroon
Bank financing is an engine of economic growth, mainly where financial intermediation is more advanced. The public authorities are therefore faced with the obligation to advocate for the resilience of the financial system. As part of their assignments, supervisors are working to put in place prudential regulation that would require banks to have a solid financial base to face the various risks and perils. Although the financial crisis has confirmed the need for adjustments in prudential regulation, the financial institutions have denounced the high cost of the new Basel requirements, a cost that would inevitably weigh on the banking activity and, consequently, on the economic activity. Based on this observation, we are conducting an impact study whose objective would is to evaluate and demonstrate the impact of the implementation of the Basel III agreements in Cameroon. Keywords: Banking; Basel III regulations; solid financial base; financial institutions; DOI: 10.7176/RJFA/10-13-05 Publication date:July 31st 201
Modelling Default Risk of Borrowers: Evidence from Online Peer to Peer Lending Platforms in Australia
Peer to Peer lending has the capacity to transforming the mass banking industry worldwide but credit risk modelling remains the core challenge of the platform. The general objective of this study is to analyse the credit default risk of borrowers of Peer to Peer online lending platform based in Australia. Specific objectives include the following; To identify the loan information applicants provide to request for a loan facility,Using RateSetter.com published data on loans to predict the likelihood of credit risk of the platform. In this article, we employed binary logistic regression model to assess the likelihood of loan default. Based on the mathematical approach and the nature of dependent variable, we grouped variables into categorical, numerical-continuous as well as binary. The dependent variable is dichotomous whilst real-life dataset was retrieved from a popular and competitive online lending platform based in Australia from 2014-2017. We identified that early repayment, no mortgage tenant; car, debt consolidation, investment, major events, professional services, 3-year loan duration, 4-year loan duration, interest rate and income have significant influence on borrowers’ likelihood to default. Our empirical coefficients suggest that, there is 83.4% likelihood of borrowers default rate and hence recommended a critical examination of borrowers’ information presented to the platform. This paper fulfills the need to examine the credit information provided by loan applicants. Similarly, it endeavors to predict the possibility of borrowers default risk and the reasons contributing to online lending credit default risk. Keywords: Credit Risk, Peer To Peer Online Lending, Binary Logistic Regression DOI: 10.7176/RJFA/10-2-0
Analysis of independent risk factors for progression of different degrees of diabetic retinopathy as well as non-diabetic retinopathy among type 2 diabetic patients
PurposeTo study the independent risk factors for development of different degrees of diabetic retinopathy (DR) as well as non-DR (NDR) among type 2 diabetic patients.MethodsThis cross-sectional study included 218 patients with type 2 diabetes between January 2022 and June 2022. All the patients were divided into two groups: the DR group and the NDR group. The DR group was subdivided into the mild, moderate and severe non-proliferative DR (NPDR) group and the proliferative DR (PDR) group. Data recorded for all patients included age, gender, duration of diabetes, blood pressure, glycated hemoglobin (HbA1c), fasting blood glucose (FBG), blood lipids, best corrected visual acuity (BCVA), intraocular pressure (IOP), axial length (AL), anterior chamber depth (ACD), and renal function. Logistic regression methods were used to analyze the risk factors for DR.ResultsThe prevalence of DR in type 2 diabetes was 28.44%. The duration of diabetes, age, mean arterial pressure (MAP), HbA1c, FBG, urinary albumin/creatinine ratio (UACR), BCVA, AL, and ACD were significantly different between the DR and the NDR groups (p < 0.05). Multivariate logistic regression analysis identified age, FBG, UACR, and AL as the independent risk factors for DR (OR = 0.843, 2.376, 1.049, 0.005; p = 0.034, 0.014, 0.016, p < 0.001).ConclusionYoung age, short AL, higher levels of FBG and UACR were the independent risk factors for the progression of DR in type 2 diabetes
E-Cadherin/β-Catenin Complex and the Epithelial Barrier
E-Cadherin/β-catenin complex plays an important role in maintaining epithelial integrity and disrupting this complex affect not only the adhesive repertoire of a cell, but also the Wnt-signaling pathway. Aberrant expression of the complex is associated with a wide variety of human malignancies and disorders of fibrosis resulting from epithelial-mesenchymal transition. These associations provide insights into the complexity that is likely responsible for the fibrosis/tumor suppressive action of E-cadherin/β-catenin
Outage and Capacity Performance Evaluation of Distributed MIMO Systems over a Composite Fading Channel
The exact closed-form expressions regarding the outage probability and capacity of distributed MIMO (DMIMO) systems over a composite fading channel are derived. This is achieved firstly by using a lognormal approximation to a gamma-lognormal distribution when a mobile station (MS) in the cell is in a fixed position, and the so-called maximum ratio transmission/selected combining (MRT-SC) and selected transmission/maximum ratio combining (ST-MRC) schemes are adopted in uplink and downlink, respectively. Then, based on a newly proposed nonuniform MS cell distribution model, which is more consistent with the MS cell hotspot distribution in an actual communication environment, the average outage probability and capacity formulas are further derived. Finally, the accuracy of the approximation method and the rationality of the corresponding theoretical analysis regarding the system performance are proven and illustrated by computer simulations
Establishment and characterization of clear cell renal cell carcinoma cell lines with different metastatic potential from Chinese patients
Neurophysiological features of STN LFP underlying sleep fragmentation in Parkinson’s disease
Background: Sleep fragmentation is a persistent problem throughout the course of Parkinson’s disease (PD). However, the related neurophysiological patterns and the underlying mechanisms remained unclear. Method: We recorded subthalamic nucleus (STN) local field potentials (LFPs) using deep brain stimulation (DBS) with real-time wireless recording capacity from 13 patients with PD undergoing a one-night polysomnography recording, 1 month after DBS surgery before initial programming and when the patients were off-medication. The STN LFP features that characterised different sleep stages, correlated with arousal and sleep fragmentation index, and preceded stage transitions during N2 and REM sleep were analysed. Results: Both beta and low gamma oscillations in non-rapid eye movement (NREM) sleep increased with the severity of sleep disturbance (arousal index (ArI)-betaNREM: r=0.9, p=0.0001, sleep fragmentation index (SFI)-betaNREM: r=0.6, p=0.0301; SFI-gammaNREM: r=0.6, p=0.0324). We next examined the low-to-high power ratio (LHPR), which was the power ratio of theta oscillations to beta and low gamma oscillations, and found it to be an indicator of sleep fragmentation (ArI-LHPRNREM: r=−0.8, p=0.0053; ArI-LHPRREM: r=−0.6, p=0.0373; SFI-LHPRNREM: r=−0.7, p=0.0204; SFI-LHPRREM: r=−0.6, p=0.0428). In addition, long beta bursts (>0.25 s) during NREM stage 2 were found preceding the completion of transition to stages with more cortical activities (towards Wake/N1/REM compared with towards N3 (p<0.01)) and negatively correlated with STN spindles, which were detected in STN LFPs with peak frequency distinguishable from long beta bursts (STN spindle: 11.5 Hz, STN long beta bursts: 23.8 Hz), in occupation during NREM sleep (β=−0.24, p<0.001). Conclusion: Features of STN LFPs help explain neurophysiological mechanisms underlying sleep fragmentations in PD, which can inform new intervention for sleep dysfunction. Trial registration number: NCT02937727
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