Economic evaluation of nivolumab for the treatment of second-line advanced squamous NSCLC in Canada: a comparison of modeling approaches to estimate and extrapolate survival outcomes

Background Lung cancer is the most common type of cancer in the world and is associated with significant mortality. Nivolumab demonstrated statistically significant improvements in progression-free survival (PFS) and overall survival (OS) for patients with advanced squamous non-small cell lung cancer (NSCLC) who were previously treated. The cost-effectiveness of nivolumab has not been assessed in Canada. A contentious component of projecting long-term cost and outcomes in cancer relates to the modeling approach adopted, with the two most common approaches being partitioned survival (PS) and Markov models. The objectives of this analysis were to estimate the cost-utility of nivolumab and to compare the results using these alternative modeling approaches.

Methods Both PS and Markov models were developed using docetaxel and erlotinib as comparators. A three-health state model was used consisting of progression-free, progressed disease, and death. Disease progression and time to progression were estimated by identifying best-fitting survival curves from the clinical trial data for PFS and OS. Expected costs and health outcomes were calculated by combining health-state occupancy with medical resource use and quality-of-life assigned to each of the three health states. The health outcomes included in the model were survival and quality-adjusted-life-years (QALYs).

Results Nivolumab was found to have the highest expected per-patient cost, but also improved per-patient life years (LYs) and QALYs. Nivolumab cost an additional $151,560 and $140,601 per QALY gained compared to docetaxel and erlotinib, respectively, using a PS model approach. The cost-utility estimates using a Markov model were very similar ($152,229 and $141,838, respectively, per QALY gained).

Conclusions Nivolumab was found to involve a trade-off between improved patient survival and QALYs, and increased cost. It was found that the use of a PS or Markov model produced very similar estimates of expected cost, outcomes, and incremental cost-utility.     

Cooperation vs. competition in R&D: The role of stability of equilibrium

We consider a model in which firms first choose process R&D expenditures and then compete in an output market. We show the symmetric equilibrium under R&D competition is sometimes unstable, in which case two asymmetric equilibria must also exist. For the latter, we find, in contrast to the literature that total profits are sometimes higher with R&D competition than with research joint venture cartelization (due to the cost asymmetry of the resulting duopoly in the noncooperative case). Furthermore, these equilibria provide another instance of R&D-induced firm heterogeneity.     

Destination image,on-site experience and behavioural intentions: path analytic validation of a marketing model on domestic tourists

Despite its contribution to the national economy, domestic tourism is one of the most neglected and under-researched forms of tourism in the literature. This study tested an integrated path model examining the interrelationships between destination image, perceived quality, satisfaction and behavioural intentions, using domestic tourists who visited Eilat, Israel. The findings support the hierarchical relationships between image, quality, satisfaction and behavioural intentions. In addition, the affective image component was found to exert a far greater impact on the overall destination image than the cognitive component. The study establishes a better understanding of domestic tourists’ destination image and behavioural intention formulation. It also provides a number of implications for destination managers targeting the voluminous domestic segment.     

The moderating effect of innovation on the relationship between environmental and financial performance: Evidence from high emitters in Australia

This study examines whether environmental-related innovation moderates the association between environmental and financial performance measured respectively as carbon emissions and return on assets (ROA). The sample comprises 119 companies subject to Australia's National Greenhouse Energy Reporting Act (NGER) for the period 2009–2017. The results show that environmental innovation positively moderates the relationship between environmental performance and financial performance. The findings also imply that the impact of environmental innovation in improving environmental performance is observable with a 1-year lag. The results are robust to the alternative financial performance measures of Tobin's Q and Altman's Z score. The findings have important implications for company managers and policymakers and provide useful information on innovation's role in enhancing environmental and financial performance.     

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.     

Testing the impact of a promotional video on destination image change: application of China as a tourism destination

This study empirically examines the potential effects of a promotional video on the image change of China as a travel destination. The analysis is based on an experimental study conducted among young, international short‐term employees in the USA. Despite positive changes in almost all the destination attributes as a result of watching the promotional video, the structure of the image constructs remains fairly stable, providing critical insights on the potential role of publicity campaigns in affecting destination images. Results of the study reveal that China's image consists of mixed and often contrasting representations, especially the polarity of modernisation and progress versus nature and history. It was found that the dominant factor affecting the respondents' behavioural intentions was the cultural and nature tourism dimension. Although other image dimensions exhibit influence as well, findings of this study suggest that perceived value should be a strategic focus in promoting China as a desirable travel destination, in addition to culture and nature tourism. This paper ends with conclusions and implications for both research on destination image and destination marketing in China. Copyright © 2009 John Wiley & Sons, Ltd.     

On Environmental Regulation of Oligopoly Markets: Emission versus Performance Standards

By specializing Montero’s (J Environ Econ Manag 44:23–44, 2002) model of environmental regulation under Cournot competition to an oligopoly with linear demand and quadratic abatement costs, we extend his comparison of firms incentives to invest in R&D under emission and performance standards by solving for a closed form solution of the underlying two-stage game. This allows for a full comparison of the two instruments in terms of their resulting propensity for R&D and equilibrium industry output. In addition, we incorporate an equilibrium welfare analysis. Finally, we investigate a three-stage game wherein a welfare-maximizing regulator sets a socially optimal emission cap under each policy instrument. For the latter game, while closed-form solutions for the subgame-perfect equilibrium are not possible, we establish numerically that the resulting welfare is always larger under a performance standard.     

Overnight Covered Interest Parity:Theory and Practice

This study shows, both theoretically and empirically, that in a world where capital as well as exchange markets are imperfect it is incorrect to employ mid-market rates to estimate CIP relationships. Developing and using the correct specification, we estimated covered interest parity relationships between the overnight U.S. Euro-dollar and Canadian interbank markets, for the 1986-1992 period. It was found that covered interest parity holds for both directions. However, the speed and pattern of adjustments with which potential arbitrage profits are eliminated are not symmetric between U.S. Euro-dollar and Canadian interbank markets. [GI51     

Investigating the Interrelationships among Success Measures of Open Source Software Projects

Open source software (OSS) has attracted extensive attention from researchers and scholars. This increasing attention is a result of the remarkable growth in the number of OSS applications in recent years. Despite an increased number of studies on OSS project success, the interrelationships among different success indicators of OSS projects are not well understood in literature. The present study reports on the interrelationships between the success measures of OSS projects, as defined by the ability of the project to attract user and developer interest, release management, project activity, and development sustainability. To test the relationships hypothesized, we gathered data from 1409 OSS projects over time (in two snapshots over a period of eight months). The results show the following: (a) project activity until any time period positively impacts the subsequent period’s developer interest and development sustainability; (b) development sustainability positively drives user and developer interest; (c) release frequency positively influences the next period’s developer interest, as well as development sustainability; (d) developer interest positively drives user interest. These findings have implications for both the OSS research community and OSS practitioners.