Distribution of residual autocorrelations for multiplicative seasonal ARMA models with uncorrelated but nonindependent error terms

In this paper, we consider portmanteau tests for testing the adequacy of multiplicative seasonal autoregressive moving‐average models under the assumption that the errors are uncorrelated but not necessarily independent. We relax the standard independence assumption on the error terms in order to extend the range of applications of the seasonal autoregressive moving‐average models. We study the asymptotic distributions of residual and normalized residual empirical autocovariances and autocorrelations under weak assumptions on noise. We establish the asymptotic behavior of the proposed statistics. A set of Monte Carlo experiments and an application to monthly mean total sunspot number are presented.     

Farmer organizations and maize productivity in rural Burkina Faso: The effects of the diversion strategy on cotton input loans

This study analyzes the impact of the diversion strategy of cotton inputs on maize productivity among farmer organization (FO) members in Burkina Faso, based on an endogenous treatment effect model. This impact is assessed by measuring the effects of the producers’ strategy of using part of their cotton inputs for growing other crops, such as maize. The data from a 2014 multisectoral survey in Burkina Faso were used. The main result is that maize productivity is 59.11% lower for FO members who divert their cotton inputs. We suggest the development of financing systems for cereals, similar to those in the cotton sector, and the establishment of monitoring the use of input credits.     

Service-Oriented Computing for intelligent train maintenance

The purpose of this work is to apply the servicization of enterprise information systems in maintenance, particularly in the management of the maintenance process of the component parts of trains. Service Oriented Architecture (SOA) is an architectural approach that permits servicization since it provides a flexible set of design principles used during the modeling practices (abstraction and realization). With a view to supporting the model-driven engineering of software systems, Mode Driven Architecture (MDA) is a design approach delivering a set of guidelines for the configuring of specifications in systems development. Therefore, the combination of these two approaches can be fruitful to address the challenging issues the enterprise information system is facing today. Our study is based on a methodological approach using the MDA models for the automatic generation of web service. The case study concerns a Railways Maintenance Workshop (RMW) at Sidi Bel Abbes (Algeria). Finally, the information system for the management of maintenance of the component parts of passengers and baggage railcars, using the generated solution, is realized and deployed. This software helps to have better management of the RMW by the effective planning of interventions, improve performance by increasing reliability, traceability, and availability of the equipment (parts).     

Do National Cultures Matter for External Audits? Evidence from Eastern Europe and the Middle East

Journal of Business Ethics - This study aims to examine the relationship between national cultural dimensions and the probability of a firm being externally audited. It uses a large set of...     

The impact of income redistribution on aggregate consumption

Atlantic Economic Journal -     

Cost-effectiveness of pembrolizumab in combination with chemotherapy in the 1st line treatment of non-squamous NSCLC in the US

Abstract

Aims: To describe cost-effectiveness of pembrolizumab plus platinum and pemetrexed chemotherapy in metastatic, non-squamous, NSCLC patients in the US.

Materials and methods: A model is developed utilizing partitioned survival analysis to estimate the cost-effectiveness of KEYNOTE-189 trial comparators pembrolizumab?+?chemotherapy (carboplatin/cisplatin?+?pemetrexed) vs chemotherapy alone. Clinical efficacy, treatment utilization, health utility, and safety data are derived from the trial and projected over 20 years. For extrapolating survival beyond the trial, a novel SEER population-data approach is applied (primary analysis), with separate estimation via traditional parametric extrapolation methods. Costs for drugs and non-drug disease management are also incorporated. Based on an indirect treatment comparison, cost-effectiveness of pembrolizumab?+?chemotherapy vs pembrolizumab monotherapy is evaluated for patients with programmed death-ligand 1 (PD-L1)?≥?50%.

Results: In the full non-squamous population, pembrolizumab?+?chemotherapy is projected to increase life expectancy by 2.04 years vs chemotherapy (3.96 vs 1.92), for an approximate doubling of life years. Resultant incremental cost-effectiveness ratios (ICERs) are $104,823/QALY and $87,242/life year. In patients with PD-L1?≥?50% and 1–49%, life expectancy is more than doubled (4.53 vs 1.88 years) and (4.87 vs 2.01 years), with a 32% (2.60 vs 1.97 years) increase in PD-L1?<?1% patients. Corresponding incremental costs/quality-adjusted life year (QALY) are $103,402, $66,837, and $183,529 for PD-L1?≥?50%, 1–49%, and <1% groups, respectively. Versus pembrolizumab monotherapy in PD-L1?≥?50% patients, representing current standard of care, pembrolizumab?+?chemotherapy increases life expectancy by 65% (4.53 vs 2.74 years) at an ICER of $147,365/QALY.

Limitations and conclusions: The addition of pembrolizumab to chemotherapy is projected to extend life expectancy to a point not previously seen in previously untreated metastatic non-squamous NSCLC. Although ICERs vary by sub-group and comparator, results suggest pembrolizumab?+?chemotherapy yields ICERs near, or in most cases, well below a 3-times US per capita GDP threshold of $180,000/QALY, and may be a cost-effective first-line treatment for metastatic non-squamous NSCLC patients.     

Ex ante capital position,changes in the different components of regulatory capital and bank risk

We investigate the impact of changes in capital of European banks on their risk-taking behaviour from 1992 to 2006, a time period covering the Basel I capital requirements. We specifically focus on the initial level and type of regulatory capital banks hold. First, we assume that risk changes depend on banks’ ex ante regulatory capital position. Second, we consider the impact of an increase in each component of regulatory capital on banks’ risk changes. We find that, for highly capitalized, adequately capitalized and strongly undercapitalized banks, an increase in equity or in subordinated debt positively affects risk. Moderately undercapitalized banks tend to invest in less risky assets when their equity ratio increases but not when they improve their capital position by extending hybrid capital or subordinated debt. On the whole, our conclusions support the need to implement more explicit thresholds to classify European banks according to their capital ratios but also to clearly distinguish pure equity from hybrid and subordinated instruments.