Awareness of Distributed Denial of Service Attacks' Dangers: Role of Internet Pricing Mechanisms

Denial of Service (DoS) attacks consist of overwhelming a server, a network or a Web site in order to paralyze its normal activity. The additional parameter in Distributed Denial of Service (DdoS) attacks is the distributing strategy. It means that DDoS attacks do not come from a single computer but stem from all accessible channels and servers. Consequences are multiple, ranging from system errors, temporary inability to access the Web site for normal users to challenging the actual reliability of the Internet. Despite this, Internet users show carelessness. The explanation lies in the specificities of DDoS attacks. We explore possibilities to raise users' awareness about the actual amplitude of problems caused by DDoS attacks. We suggest a careful examination of Internet pricing mechanisms and switching from flat to usage-constraining pricing schemes.     

Healthcare costs of stroke and major bleeding in patients with atrial fibrillation treated with non-vitamin K antagonist oral anticoagulants

Objective: To assess long-term healthcare costs related to ischemic stroke and systemic embolism (stroke/SE) and major bleeding (MB) events in patients with non-valvular atrial fibrillation (NVAF) treated with non-vitamin K antagonist oral anticoagulants (NOACs).

Materials and methods: Optum’s Clinformatics Data Mart database from 1/2009–12/2016 was analyzed. Adult patients with ≥1 stroke/SE hospitalization (index date) were matched 1:1 to patients without stroke/SE (random index date), based on propensity scores. Patients with an MB event were matched to patients without MB. All patients had an NOAC dispensing overlapping index date, ≥12?months of eligibility pre-index date, and ≥1 NVAF diagnosis. The observation period spanned from the index date until the earliest date of death, switch to warfarin, end of insurance coverage, or end of data availability. Mean costs were evaluated: (1) per-patient-per-year (PPPY) and (2) at 1, 2, 3, and 4?years using Lin's method.

Results: The cost differences were, respectively, $48,807 and $28,298 PPPY for NOAC users with stroke/SE (n?=?1,340) and those with MB (n?=?3,774) events compared to controls. Cost differences of patients with vs without stroke/SE were $49,876, $51,627, $57,822, and $60,691 at 1, 2, 3, and 4?years post-index, respectively (p?p?Limitations: Limitations include unobserved confounders, coding and/or billing inaccuracies, limited sample sizes over longer follow-up, and the under-reporting of mortality for deaths occurring after 2011.

Conclusions: The incremental healthcare costs incurred by patients with vs without stroke/SE was nearly twice as high as those of patients with vs without MB. Moreover, each additional year up to 4?years after the first event was associated with an incremental cost for patients with a stroke/SE or MB event compared to those without an event.     

A diagnostic m-test for distributional specification of parametric conditional heteroscedasticity models for financial data

This paper proposes a convenient and generally applicable diagnostic m-test for checking the distributional specification of parametric conditional heteroscedasticity models for financial data such as the customary Student t GARCH model. The proposed test is based on the moments of the probability integral transform of the innovations of the assumed model. Monte-Carlo evidence indicates that our test performs well both in terms of size and power. An empirical example illustrates the practical usefulness of the test and some of its possible extensions are outlined.     

Job mobility restriction mechanisms and appropriability in organizations: The mediating role of secrecy and lead time

This paper addresses the following question: does mobility restriction enhance the appropriability of R&D investments? And if so, how does this occur? We propose that mobility restriction mechanisms affect appropriability through their impact on secrecy and lead time. We test mediation hypotheses in a sample of biotechnology firms and discuss the implications for intellectual property protection strategies and human resource management.     

Designing the European Road Safety Observatory

The unavailability of consistent traffic accident data and road safety information limits the opportunities to provide target approaches to reduce road crashes. The European commission has decided to meet the demand for this data by establishing a new Road Safety Observatory. The structure and much of the initial content is being developed within the SafetyNet Integrated Project. This paper describes the structure of its key components.     

Mathematical formulation and exact solution for landing location problem in tropical forest selective logging,a case study in Southeast Cameroon

In Central Africa, creating forest roads and skid trails is one of the most costly and environmentally damaging operations for the forest's ecosystem. An optimized road network is essential for reducing construction costs and improving the sustainable management of timber resources. The location of landings is vital in the development of a future forest road network. In this study, a binary integer programming model similar to the uncapacitated facility location problem is formulated to optimize the locations of the landings. The model is applied to selective logging in Central Africa and tested on an annual logging zone in Southeast Cameroon. The results are compared to that of manual road planning, the currently used method.