Abstract:Based on the reality in China，three kinds of market competition models of network video platforms，symmetric free (FF) ，asymmetric payment (PF) and symmetric payment (PP) ，are constructed in this paper． The evolutionary mechanism of the business modes of network video platforms are revealed by analyzing and comparing the three models，and the role of the positive and negative cross-network externalities of platforms in the evolutionary mechanism of the platform business modes is analyzed． The results show that if certain differences exist between platforms，the equilibrium results and business strategies are affected by the positive and negative cross-network externalities． With the change of the positive and negative cross-networks externalities，the business modes of network video platforms will undergo three stages of evolution: “symmetric free mode”，“asymmetric payment mode”and “symmetric payment mode”． Correspondingly，the business strategy adopted by the platform will also undergo four stages: “free + advertising”，“subsidy + advertising”， “membership fee + advertising”and “pure membership fee”． However，only the FF and PP modes are the Nash equilibrium results of the network video platform competition，while the asymmetric competition (PF) could not reach the Nash equilibrium．

Abstract:Online health information service has increasingly become an effective means for health management． It is widely concerned by people from all walks of life． In order to solve the dynamic pricing and promotion strategy of online health information service，this paper considers an online health information service provider，which simultaneously provides customized health information service and free public health information service． Aiming at maximizing the profit of online health information service providers，based on the differential dynamics theory，this paper analyzes the dynamic conversion characteristics between consumers of free public health information and customized health information service，and constructs an optimal control model of dynamic pricing mechanism for health information service． The results show that for online health information service with long service periods，giving consumers a certain period of ‘free-charge period’before charging service can increase the optimal profit of online information service providers． However，for online health service with short service periods，it is not necessary to set the‘free-charge period’． Also，both the growth rate of potential customers of online health information service providers and the length of service time have significant impacts on the degree of public health information delivery． At the initial stage of online health information service，the service providers can get more profits by appropriately extending the ‘free-charge period’for high-income consumers． All these conclusions are valuable for health information service providers to make service pricing and promotion strategies．

Abstract:Given a one-to-one bi-modal transportation network，the origin and the destination is connected by a highway with a bottleneck and a parallel transit line． Based on the bottleneck model，this paper considers the spatial distribution of parking spots and develops two novel parking permit schemes: one is a parking permit scheme with a designated spot ( i.e.，the designated scheme) ; the other is a parking permit scheme with a non-designated spot ( i.e.，the non-designated scheme) ． Both of them can help commuters with permits to reserve parking spaces，but the former predetermines a spot for the auto-commuter． By introducing a time-var-ying road toll，four traffic management schemes are proposed and the strategy optimization is investigated． The objective is to minimize the system travel cost and traffic emission costs simultaneously． It is found that the practice of parking permit scheme eliminates the competition for parking spots and the individual travel cost of drivers is thus reduced． Besides，the system performance reaches the optimum when both time-varying road tolls and the designated scheme are applied． However，the practice of roadway charge might be controversial． The non-designated scheme can be considered as a sub-optimal solution．

Abstract:Agriculture is one of the most weather-sensitive industries． Adverse weather affects agricultural productions，and compels the“company ＆ farmer”pattern to face high default rates． To solve this issue，this paper considers an example of late spring coldness，and builds a decision model for a two-stage agricultural supply chain consisting of a risk-averse farmer and a risk-neutral company． By employing the CVaＲ criterion，a decision function is constructed for the risk-averse farmer． Further，an improved price protection contract is put forward based on adverse weather index． The results show that the improved price protection contract can solve the distortion in agricultural material input levels． However，it cannot eliminate the negative impacts of adverse weathers． Hence，a weather put option contract is developed based on the improved price protection contract． It is found that the weather put option contract can fully coordinate the supply chain，and the coordination will not be affected by the change of adverse weathers． In addition，the weather put option can help the company transfer the adverse weather risks，so that the relative stable revenues of both the company and the farmer are guaranteed．

Abstract:Considering that the trading mechanism of TAIEX options (TXO) market is similar to exchange traded options markets of Mainland China，and taking into account data availability，this paper studies the impact of inventory risk on market maker’s quotation and estimates the size of the impact based on the tick-by-tick data of TXO market． Following the method proposed by Muravyev for decomposing the price impact of trades into inventory risk and asymmetric information risk components，this paper derives a new equation． Empirical results show that inventory risk component is far greater than asymmetric information risk component in TXO market． Besides，this paper also shows that inventory risk has a significant impact on option returns using the daily data． The conclusions illustrate the importance of inventory risk management to market makers．

Abstract:: The effect of Federal Ｒeserve’s monetary policy on the ＲMB foreign exchange market pressure will change with the monetary policy mode and different economic environments in different economic periods． Therefore，based on the theory of spillover effect of international monetary policy，this paper first tests the nonlinear relationship between Federal Ｒeserve’s monetary policy and ＲMB foreign exchange market pressure， then constructs a factor-augmented vector autoregressive model with time-varying coefficients and stochastic volatility． The model is used to study the non-linear impact of Federal Ｒeserve’s monetary policy on ＲMB exchange market pressure from the aspect of quantitative monetary policy and price-based monetary policy． It is found that: First，in the period of economic prosperity and economic stability，the quantitative easing monetary policy of Federal Ｒeserve mainly causes appreciation pressure of ＲMB exchange market through capital and financial accounts，while the price-based easing monetary policy of Federal Ｒeserve mainly causes depreciation pressure of ＲMB exchange market through capital and financial accounts． Second，in the period of economic depression，the quantitative easing monetary policy of Federal Ｒeserve mainly causes depreciation pressure of ＲMB exchange market through the current account，while the price-based easing monetary policy of Federal Ｒeserve mainly causes appreciation pressure of ＲMB exchange market through the current account． This paper predicts that Federal Ｒeserve will implement the price-based easing monetary policy，and suggests that the Central Bank of China implement the same price-based easing monetary policy，to reduce the depreciation pressure of ＲMB and maintaining the stability of the ＲMB exchange rate．

Abstract:HAＲ-type models can be used to describe the proportion of contributions by different class of traders (Heterogeneous) ． They are widely used in empirical study and their performance is good in financial market volatility forecasting． The empirical results show the HAＲ-type models can be used to partly capture the long memory which is very important for financial market，but the performance is very limited． However， AＲFIMA models are very good at describing long memory． Therefore，based on the advantages of above mentioned two models，a new model: HAＲFIMA is proposed and developed further into an HAＲFIMA-type model． Then the HAＲFIMA-type model is used to forecast the realized volatility (ＲV) of S＆P 500 and SSEC． The empirical results show that our HAＲFIMA-type model can be used to capture long memory more accurately，and that the out-sample forecasting performance is better than other models． This conclusion is also robust．

Abstract:This paper presents the discpritive statistics and analysis on the supported research project on the field of Complexity Science and its application to Economics by the Department of Management Sciences，National Natural Science Foundation of China (NSFC) since 1986． Meanwhile，it reviews the current research on Complexity Science and Complexity Economics that emerged from the mix of Complexity Science and Economics，and sumerizes the academic progress achieved by domestic and foregin scholars，as well as the trend in the near future． Based on this work，we are intend to provide a reference for the researcher in the related areas，so that to push the frontier of studies on the management of complexity system，and further offer policy implications for the 14th five-year subject plan of the Department of Management Sciences，as well as theorectic support for the improvement on national economic governance system