Prediction of the next hypercalcemia free period: application of random effect models with selection on first event

The length of repeated hypercalcemia free periods of patients with bone metastasis of breast cancer with at least one hypercalcemic event was modelled according to a generalized linear mixed model formulated in terms of transition probabilities and according to a latent variable model. In the former case the periods were assumed to be lognormally distributed with two variance components (patients and residue). In the latter case the conditional intensity given a patient was assumed to be the intensity of the Weibull distribution, while the random patient effect (frailty) was assumed to be drawn from a gamma distribution. In both cases the selection of only patients with at least one hypercalcemic event was taken into consideration. In both models the variance of the patient effect turned out to be negligible. For the second and later periods the Weibull appeared to fit better than the lognormal model. For the first period there was almost no information available.     

所有权与自然垄断产业规制——组合模式及选择

对于自然垄断产业采用何种所有权结构的规制模式,在理论研究与实践操作中都存在着多样化的选择。本文主要比较分析了民营外生规制、国有内生规制和混合所有权规制三种不同组合模式,并认为混合所有权规制模式较好地兼容了其他模式的优点,可以成为自然垄断产业改革与治理进程中的一个可取路径。欧盟国家自然垄断产业的改革经验,从实践上证明了混合所有权规制模式的可行性,尽管其也存在一定的局限性。同时,本文认为对于转型改革时期的中国,针对自然垄断行业的国有企业,可以考虑采用混合所有权规制模式的改革路径,通过股权开放的形式放松民营资本进入自然垄断产业的行业管制,并有效、平稳地建立起自然垄断产业规制体系。     

国有股权参股与民营重污染企业绿色治理

由于生态环境投入的外部性和资本的逐利性,民营重污染企业的绿色治理是我国企业绿色治理的重点和难点.本文分析了国有股权参股对民营重污染企业绿色治理的影响机理,并以2008～2019年A股上市的民营重污染企业为研究样本进行了实证检验.研究发现,国有股权参股能够通过治理效应和资源效应促进民营重污染企业绿色治理;相对于污染风险较...     

中国移动通信业价格竞争本质解析

中国移动通信业的价格竞争,经过了无价格竞争阶段、显性价格竞争阶段、隐性价格竞争阶段、后价格竞争阶段的演化,体现了制度调节与市场选择并行的内在规律性,也增进了市场协调、提高了市场效率。中国移动通信业价格竞争具有非合作博弈的特性,行业管制与市场选择共同推动了竞争的有序化。因此,要实现中国移动通信市场的有效竞争,市场机制的作用是有限的,还离不开适当的政府行政参与下的不对称管制政策,而且不对称管制政策也需要根据市场变化进行调整和改进。     

Kreps & Scheinkman with Product Differentiation

Kreps and Scheinkman (1983)’s celebrated result is that in a two-stage model of a market with homogeneous products in which firms noncooperatively pick capacities in the first stage and set prices in the second stage, the equilibrium outcome is that of a one-shot Cournot game. This note derives capacity best response functions for the first stage and extends the Kreps and Scheinkman result to the case of differentiated products.     

FREE VERSUS SECOND‐BEST ENTRY IN COURNOT OLIGOPOLIES WITH FIRM‐SPECIFIC NETWORKS

This paper endogenizes the number of firms in an industry with positive network effects, complete incompatibility, and firms that compete in quantity. To this end, we compare two possibilities: free entry and second‐best number of firms (the one that maximizes social welfare). We show that with business‐stealing competition, free entry yields, in general, more firms than the socially optimal solution. In addition, we find that by the nature of the industry with firm‐specific networks, total production may be greater or lower under free entry than with a regulator; moreover, some industries attain their maximum social welfare with a monopoly.     

The rise of Mexican entrepreneurial migration to the United States: A mixed‐embeddedness approach

Although many studies have analyzed the behavior of high‐skilled migration to the United States, few have focused on the escalating migration of Mexican entrepreneurs, and particularly on the determinants of this kind of high‐skilled migration. This article addresses this gap through a qualitative approach conforming to quantitative procedures, based on 20 in‐depth interviews applied to Mexican entrepreneurs working and/or living in the United States. Theoretically, a mixed‐embeddedness approach guides this research because it allows examining both the individual characteristics of Mexican entrepreneurs, and the influence of the home and host countries' institutional contexts on their business endeavors. Findings revealed Mexico's institutional weaknesses, such as insecurity, corruption, and bureaucracy, are important drivers of migration but so are the perception of a friendly U.S. fiscal system, the search for a better quality of life, and the appeal of a more transparent business environment.     

Bertrand versus Cournot competition in a downstream mixed oligopoly with foreign ownership

Focusing on foreign ownership in the private firm, we examine the Cournot-Bertrand comparison in a mixed oligopolistic market with vertical market structure. We have found that if public and private firms were charged with uniform price for their inputs, then Cournot-Bertrand ranking in market outcomes confirms those obtained by Ghosh and Mitra (2010). This implies that under uniform pricing in the upstream sector, the vertical market structure does not have substantial influences on Cournot-Bertrand ranking. However, if discriminatory pricing is adopted, firm's profits, output, and social welfare are often reversed to those obtained from uniform pricing in the upstream sector. Given the closeness of products, if the share of foreign ownership is sufficiently low, social welfare in Cournot competition can exceed that of Bertrand competition, contrasting with the standard welfare ranking that Bertrand welfare is strictly higher than Cournot. This implies that Cournot competition can be more socially desirable than Bertrand in mixed oligopoly with vertical market structure if discriminatory pricing scheme is adopted by foreign upstream monopolists.     

PERFORMANCE‐BASED FEE CONTRACT AND RISK‐TAKING STRATEGY IN ASSET MANAGEMENT TOURNAMENT

This paper investigates how performance‐based fee (PBF) contracts affect strategic risk‐taking behaviours of fund managers in an asset management tournament. In the perfect equilibrium, managers with better mid‐year performance will hold the risky asset with a higher probability in the remaining of the year, compared to managers with poorer mid‐year performance. If the volume of the cash flow into the winner fund is contingent on its level of success, the winning fund will take a more aggressive approach. When the PBF contract pays more heed to relative performance against the benchmark, managers are more likely to adopt aggressive strategies.     

Emotions,deliberations, and end‐of‐life products

Death is inevitable; yet, not all consumers prepare for death by purchasing end‐of‐life (EOL) products. Using the theory of reasoned action (TRA) and the dual‐process model framework, this study aims to examine the role of emotions and cognitions in influencing consumers' decisions to engage in planning for death. A mixed methodology design was used. Study 1, a qualitative study, uncovered positive and negative emotions and deliberative reasoning that comprise consumers' EOL purchase decision process. Study 2, a quantitative study, confirmed that emotions and deliberations independently and jointly influenced consumers' EOL attitude and behavior and that emotions affected deliberations for both prepaid funerals and wills. Subjective norms outperformed attitude in predicting both products' purchase behavior. These finding supported the dual‐process model of behavior and the TRA in the EOL research context and contributed to the EOL literature by investigating the effects of emotions and deliberations concurrently; thus validating the important role of emotions in influencing EOL planning and purchase. In light of our findings, marketers could, after due cognizance of the morbidity and sensitivity of the topic, develop actionable promotional and segmentation strategies for EOL products and other emotion‐laden, unsought products and service.