益生菌乳饮料中活菌数影响因素的优化研究

本文通过分析其加工工艺,对发酵温度、非脂乳固体含量及接种量进行单因素试验,结果表明在发酵温度36~38℃、非脂乳固体含量10%~20%、菌种添加量0.03%~0.07%时益生菌乳饮料中活菌数最多。     

Pricing double barrier options under a volatility regime-switching model with psychological barriers

The prices of lots of assets have been proved in literature to exhibit special behaviors around psychological barriers, which is an important fact needed to be considered when pricing derivatives. In this paper, we discuss the valuation problem of double barrier options under a volatility regime-switching model where there exist psychological barriers in the prices of underlying assets. The volatility can shift between two regimes, that is to say, when the asset price rises up or falls down through the psychological barrier, the volatility takes two different values. Using the Laplace transform approach, we obtain the price of the double barrier knock-out call option as well as its delta. We also provide the eigenfunction expansion pricing formula and examine the effect of the psychological barrier on the option price and delta, finding that the gamma of the option is discontinuous at such barriers.     

International automotive production networks: how the web comes together

This paper aims to provide empirical evidence for the connections between new trade theory and the spatial distribution of economic activities, considering the results obtained by the literature on New Economic Geography as a starting point. To do this, we apply Social Network Analysis specifically to the World Automotive Trade Network. We explore the structural features of the auto network for the years 1996 and 2009 using data on trade flows for 172 countries. Our findings suggest that the auto network has become denser, more extensive and more integrated over time, depicting a center-periphery structure in which regional clusters play a prominent role. In this configuration, strong agglomeration forces generated by companies’ desire for large and rich market access with minimum transportation costs are balanced by the search for new high-potential markets.     

Implications of the Dual Banking System in the US

This paper examines the differences in characteristics of federal and state chartered banks by using individual commercial bank’s data sets from 1984 to 2006. The findings indicate significant differences between these two groups of banks in terms of their asset and liability management strategies. In line with these differences, credit channel of monetary policy is found to work differently for state and federal banks. Federal banks are found to be more responsive to monetary policy changes.     

Inter-firm collaboration in new product development in Chinese pharmaceutical companies

High-tech firms increasingly rely on inter-firm collaboration (IFC) in new product development (NPD). While there is a growing research interest in exploring the economic rationale of IFC through the transaction cost economics (TCE) and the resource synergy of IFC through the resource-based view of the firm (RBV), little attention has been given to the institution-based view (IBV) that also has important implications for firms’ choice of IFC. In particular, how national institutional environment affects IFC in the NPD process remains under-researched. This study aims to contribute to the literature by extending our understanding of the role of IFC in firms’ NPD process, taking into account transactional, resource, and institutional factors. Based on a case study of two firms: a state-owned and a private pharmaceutical firm in China, our research identifies three key forms of IFC, which are dynamic at different stages of NPD and contingent upon an array of institutional, resource, and transactional rationales underpinning firms’ choice of different forms of IFC. Our study is the first one that investigates the role of IFC in the NPD process bringing together the IBV, RBV, and TCE perspectives.     

Looking inside the spiky bits: a critical review and conceptualisation of entrepreneurial ecosystems

The concept of entrepreneurial ecosystems has quickly established itself as one of the latest ‘fads’ in entrepreneurship research. At face value, this kind of systemic approach to entrepreneurship offers a new and distinctive path for scholars and policy makers to help understand and foster growth-oriented entrepreneurship. However, its lack of specification and conceptual limitations has undoubtedly hindered our understanding of these complex organisms. Indeed, the rapid adoption of the concept has tended to overlook the heterogeneous nature of ecosystems. This paper provides a critical review and conceptualisation of the ecosystems concept: it unpacks the dynamics of the concept; outlines its theoretical limitations; measurement approaches and use in policy-making. It sets out a preliminary taxonomy of different archetypal ecosystems. The paper concludes that entrepreneurial ecosystems are a highly variegated, multi-actor and multi-scalar phenomenon, requiring bespoke policy interventions.     

A principal component model for forecasting age- and sex-specific survival probabilities in Western Europe

The assessment of future mortality is of high importance in many areas where the allocation of future resources has to be planned in time, especially in social security and private life insurance. This contribution represents an extension of the classic forecasting approaches of Bell–Monsell and Lee–Carter. Based on a forecast of the first two principal components, age- and sex-specific survival probabilities for 18 Western European countries are predicted simultaneously until the year 2070. In addition to the correlations in the mortality trends between the age groups and the genders, international trends in mortality are captured as well. A major improvement in the classic Lee–Carter models is the adequate quantification of the uncertainty associated with the whole system of variables by stochastic simulation of all remaining principal components with simple time series models. The model’s easy applicability to further analyses is illustrated by forecasting the median life span as well as the resulting Gender Gap for Germany, France, and Italy.     

The Empire Strikes Back: Digital Control of Unfair Terms of Online Services

The authors argue that it is possible to partly automate the process of abstract control of fairness of clauses in online consumer contracts. The authors present a theoretical and empirical argument for this claim, including a brief presentation of the software they have designed. This type of automation would not replace human lawyers but would assist them and make their work more effective and efficient. Policy makers should direct their attention to the potential of using algorithmic techniques in enforcing the law regarding unfair contractual terms, and to facilitating research on and ultimately implementing such technologies.