Abstract:Previous studies on job search are mostly focused on the theoretical models rather than the empirical studies． This paper contributes to the empirical research in the area of job search，by using its classical models and identifing the effect of social network on the job search． An experimental study is conducted to examine whether the social network，which is used to gain information，has a significant influence on the searcher＇s behavior． The hypotheses formulated are that the availability of social network will significantly increase the expected wage of job searchers and will shorten the duration of searching in labor market． The findings confirm that the social network do have positive effect on the searching process and increases the efficiency of the labor market．

Abstract:This paper discusses joint decisions on inventory and pricing control with constraints in the supplier’s capacity in two types of market searches—customer-driven search ( CDS) and retailer-driven search ( ＲDS) —resulted from lack of or imbalances in inventory． By compariing between our results and those of existing literature without supplier’s capacity and inventory uncertainty，we concluded that，when the variation of random capacity is large enough，the retailer will increase the order quantity instead of changing pricing decisions． Otherwise，to reduce retail price is a better choice for the retailer． Furthermore，the equilibrium safety stock and retail price in CDS are always higher than those in ＲDS． Then，through analyzing the sensitivity of search intensity，we demonstrate that the equilibrium safety stock，retail price and sales are increasing in the search intensity in CDS，and not always increasing in ＲDS． Finally，penalty cost of stockout and transportation cost are considered to extend our model．

Abstract:This paper studies the joint optimal pricing problem when the demands for multiple types of rooms depend on the manager’s pricing strategies． First，we present an idea that all room types are classified by whether their demands have interactive impacts． Second，under the assumption of customers staying at the hotel only for a single night，we describe the dynamic pricing process of the hotel manager with a stochastic and dynamic model，and describe the customer’s choice behavior with a Nested Logit (NL) discrete choice model． We also design an algorithm to solve the optimal price strategy． Experimental results show that，compared to cases that do not consider the influence of pricing strategies among different types of rooms，the model that consider the interactive impacts of demands between different types of rooms can achieve more benefit，higher expectation of room occupancy rate and lower average room price．

Abstract:The measures of internal control monitoring are important in improving management and reducing the probability of internal control weaknesses for modern enterprises． This paper presents a distribution model that determines the optimal amount to invest in the internal control monitoring for modern enterprises． The model takes into account the defect rate of internal controls and the reliability of processes． The defect rate of internal controls can be decreased by investing in the internal control monitoring． Consequently，the reliability of processes can be raised． This paper utilizes the theory of reliability to measure the utility of the investment of internal control monitoring． The model proposes to maximize the utility of the firm subject to a given level of investment desired by the management． It focuses on how to allocate the amount of investment to maximize an enterprise’s utility． In a series system，if the internal control strength of each process is different，the product of the optimal investment and the internal control strength of the process is related to the probability of the error occurring． But in a parallel system，if the internal control strength of each process is different，the amount of investment is related to the internal control strength of all processes． The investment is averaged for each process，if the internal control strength of each process is the same． Further，the utility in a parallel system is higher than that in a series system．

Abstract:Production function of the expected outputs and undesirable outputs are constructed in this article firstly，and then non-convex nonparametric least squares estimation considering the undesirable outputs is studied． When αi1，β' i1，αi2，β' i2，are given，explicit expression of f and g can be obtained． According to DEA considering undesirable outputs and CNLSUO，relationship between the two fitting curves can be calculated． For the actual outputs of each firm，the estimation of CNLSUO is never larger than that of DEA． Empirical analysis shows that the DEA estimation considering the desirable and undesirable outputs is good． The analysis of statistical properties of methods for environmental efficiency evaluation，including least squares estimation of DEA considered undesirable outputs is bound to expand the scope of non-parameter statistical properties of DEA，which promote the further integration and development of statistics and operations．

Abstract:Based on the survival analysis theory，we split the effects of market characteristics on the trading intensity into a transitory (uninformed) and a permanent (informed) component． We test the effects of market status on informed and uninformed trading using the high frequency data of 10 liquid stocks and 10 illiquid stocks of SSE． These data cover from June，2006 to September，2006． Our results show that，when trading volume increases，the trading intensity of informed (uninformed) trading increases (decreases) in the two markets． When the spreads increase，the trading intensity of informed (uninformed) trading increases (decreases) in the liquid market，while the trading intensity of informed (uninformed) trading decreases (increases) in the illiquid market． Moreover，we observe that the informed trades are highly persistent in the two markets，but that the uninformed trades respond negatively to the informed trades in the liquid market and the uninformed trades respond positively to the informed trades in the illiquid market．

Abstract:How the micro-agent effectively exerts its risk control ability has always been a research focus． There are plenty literatures which have made empirical studies concerning the performance of financial holding companies from the viewpoints of both economies of scale and economies of scope． We have found few literatures digging into the risk management mechanism of financial holding companies from the perspective of control rights allocation． Based on the control rights allocation theory in organizational design and the incomplete contract theory，we construct a risk control rights allocation model of the financial holding companies and study the functions of the micro-agent’s behaviors in risk management． The analysis shows that: when confronted by internal and external risk shocks，the financial holding company could diversify and transfer the risk，enhance the risk control ability and improve the return by decentralizing or centralizing the risk control rights． To validate the above conclusions，we select the sample data of Chinese financial holding companies and individual banks during the financial crisis and make an empirical comparison of their risk and return performances． The empirical results show that the profitability of financial holding companies is significantly higher than that of individual banks; their risk level is lower than that of individual banks． In addition，we study the time-varying effect of the financial crisis on the sample companies，and the results confirm the impact of the financial crisis on China’s financial sector．

Abstract:According to the annual reports of listed companies，a correlated network of the listed companies and their main stock holders are established． Taking into account the mutual influences，resulted from reduced cash flows or the fracture of capital chain，between the listed companies and the main stock holders，a susceptible-infected-removed model of crisis spreading (SIR) in the stock markets is established． Then，a numerical computation is used to analyze the crisis spreading in the correlated networks when the networks meet the random failure or the intentional attacks． If there are some failures or attacks on the large-scale listed companies or large-scale holding companies (Hub vertices) in the networks，the crisis will spread in a high speed and cause catastrophic damages． In this condition，the networks show a obvious vulnerability; and the stock markets may show domino effects． The research approaches in this paper are helpful for further researches on the transmission mechanism of the economic crisis．