Prediction of NFT Sale Price Fluctuations on OpenSea Using Machine Learning Approaches

The rapid expansion of the non-fungible token(NFT)market has attracted many investors.However,studies on the NFT price fluctuations have been relatively limited.To date,the machine learning approach has not been used to demonstrate a specific error in NFT sale price fluctuation prediction.The aim of this study was to develop a prediction model for NFT price fluctuations using the NFT trading information obtained from OpenSea,the world’s largest NFT marketplace.We used Python programs to collect data and summarized them as:NFT information,collection information,and related account information.AdaBoost and Random Forest(RF)algorithms were employed to predict the sale price and price fluctuation of NFTs using regression and classification models,respectively.We found that the NFT related account information,especially the number of favorites and activity status of creators,confer a good predictive power to both the models.AdaBoost in the regression model had more accurate predictions,the root mean square error(RMSE)in predicting NFT sale price was 0.047.In predicting NFT sale price fluctuations,RF performed better,which the area under the curve(AUC)reached 0.956.We suggest that investors should pay more attention to the information of NFT creators.We anticipate that these prediction models will reduce the number of investment failures for the investors.

The Virtual Repeat Sale Model for the House Price Index for New Building in China

By using the characteristics of the new building in China, this article constructs the virtual repeat sale method to produce virtual repeat data which is similar to the repeat sale model on the house price index. Case-Shiller procedure and OFHEO method are used to calculate the house price index for new building in China. A discussion is given and furthering models are needed to take advantage of the virtual repeat sale data.

Women’s empowerment and food consumption:Evidence from female-headed households in Tanzania

Despite the growing recognition of women’s increasing role in the household and corresponding empowerment programs in sub-Saharan Africa,intensive research on the relationship between women’s influence and household food consumption is minimal.Using the most recent(2017-2018)national household survey data from Tanzania,this study examined the influence of women’s empowerment on household food consumption.First,we compared the monthly consumption of eight food categories between female-headed households(FHHs)and male-headed households(MHHs)using both descriptive statistics and the propensity score matching(PSM)method.Furthermore,we adopted the two-stage Linear Expenditure System and Almost Ideal Demand System model(LES-AIDS)to estimate income and price elasticities for the two household types.The results show that FHHs consume bread and cereals,fish,oils and fats,vegetables,and confectionery(sugar,jam,honey,chocolate,etc.)more than MHHs.Moreover,FHHs have a significantly higher income elasticity of demand for all food groups than MHHs.They are also more price elastic than MHHs in meat,fish,oils,fats,sugar,jam,honey,chocolate,etc.

Did weekly economic index and volatility index impact US food sales during the first year of the pandemic?

We explore the impacts of economic and financial dislocations caused by COVID-19 pandemic shocks on food sales in the United States from January 2020 to January 2021.We use the US weekly economic index(WEI)to measure economic dislocations and the Chicago Board Options Exchange volatility index(VIX)to capture the broader stock market dislocations.We validate the NARDL model by testing a battery of models using the autoregressive distributed lags(ARDL)methodology(ARDL,NARDL,and QARDL specifications).Our study postulates that an increase in WEI has a significant negative long-term effect on food sales,whereas a decrease in WEI has no statistically significant(long-run)effect.Thus,policy responses that ignore asymmetric effects and hidden cointegration may fail to promote food security during pandemics.

Correlation Analysis of Fiscal Revenue and Housing Sales Price Based on Multiple Linear Regression Model

This paper selects seven indicators of financial revenue and housing sales price in recent 19 years in China,and uses SPSS and Excel to carry out descriptive statistics,independent sample t-test,correlation analysis and regression analysis to comprehensively study the correlation between financial revenue and housing sales price in China,and establishes the relationship between financial revenue and housing sales price When the average selling price of commercial housing increases by one unit,the fiscal revenue will increase by 27.855 points.

制造商与零售商分别主导的Stackelberg博弈比较

考虑单供应商与单零售商构成的二级供应链的批发价契约,尤其是市场需求确定依赖于零售价格与零售商销售努力水平。在逻辑一致的前提下,分析了制造商占主导与零售商占主导的Stackelberg博弈,并以集成企业情况下的供应链总利润、市场需求量、市场零售价格、销售努力水平等为基准进行了比较。研究表明:零售商主导下的分散供应链效率最低。

农业节水灌溉REITs项目IRR测算研究

通过农业节水灌溉特许经营项目REITs案例研究发现,基础设施特许经营项目存在价值漏损时,可采用修正的B-S期权模型进行估值,可分配现金流用于分红的比例越高,投资收益越高,但项目的看涨期权价值越低。在项目高溢价转让的情况下,银行贷款比例越高、偿还时间越短,投资内部收益率(IRR)及投资收益可能越低;收益波动越大,看涨期权价值越大,但IRR可能会下降。采用B-S期权定价模型丰富了现有经营权类公募REITs资产估值方法,具有推广应用价值。对公募REITs产品在不同贷款比例、还款期限以及分红条件下确定合理投资收益,具有实践指导作用。

国内外融合教育研究进展的对比分析——基于WOS与CSSCI核心数据库文献共被引知识图谱解读

借助CiteSpace软件,采用文献共被引技术,对比分析了国内外“融合教育”研究的异同点。结果显示:发文量上,国外处于迅猛增长期,国内呈现稳步增长状态;研究领域方面,国外注重跨学科合作,国内聚焦于教育领域;研究热点方面,两者虽然都关注了“融合教育理论”“融合教育教师”,但国外更微观,注重模型建构与行动研究,国内更宏观,侧重国家政策分析;研究前沿方面,国外聚焦循证教育,国内侧重教师融合素养培养。基于以上分析,后续研究除需要构建面向全社会参与的融合教育运行机制外,还应开展基于循证实践的教育行动研究以及跨学科的应用与开发研究。

Factors Influencing Price of Agricultural Products and Stability Countermeasures

Factors leading to rise of prices of agricultural products mainly include tension of supply-demand relationship,promotion of production cost and circulation cost,and speculation of Refugee Capital(Hot Money).Factors leading to low price and difficult sales of agricultural products mainly include asymmetry of supply-demand information,lack of risk management tools for prices of agricultural products and decentralized and small-scaled operation of farmers.On the basis of these factors,this paper presents following countermeasures and suggestions for stabilizing prices of agricultural products:firstly,building long-effect mechanism for production and sales of agricultural products;secondly,expand the production and increase supply of agricultural products;thirdly,control the rising range of production cost for agricultural products;fourthly,enhance organization level of farmers;fifthly,promote innovation and development of risk management tools for prices of agricultural products.

The relationship between international crude oil prices and China＇s refined oil prices based on a structural VAR model

With the frequent fluctuations of international crude oil prices and China＇s increasing dependence on foreign oil in recent years, the volatility of international oil prices has significantly influenced China domestic refined oil price. This paper aims to investigate the transmission and feedback mechanism between international crude oil prices and China＇s refined oil prices for the time span from January 2011 to November 2015 by using the Granger causality test, vector autoregression model, impulse response function and variance decomposition methods. It is demonstrated that variation of international crude oil prices can cause China domestic refined oil price to change with a weak feedback effect. Moreover, international crude oil prices and China domestic refined oil prices are affected by their lag terms in positive and negative directions in different degrees. Besides, an international crude oil price shock has a signif- icant positive impact on domestic refined oil prices while the impulse response of the international crude oil price variable to the domestic refined oil price shock is negatively insignificant. Furthermore, international crude oil prices and domestic refined oil prices have strong historical inheri- tance. According to the variance decomposition analysis, the international crude oil price is significantly affected by its own disturbance influence, and a domestic refined oil price shock has a slight impact on international crude oil price changes. The domestic refined oil price variance is mainly caused by international crude oil price disturbance, while the domestic refined oil price is slightly affected by its own disturbance. Generally, domestic refined oil prices do not immediately respond to an international crude oil price change, that is, there is a time lag.

Spatial Quantitative Analysis of Garlic Price Data Based on ArcGIS Technology

In order to solve the hidden regional relationship among garlic prices,this paper carries out spatial quantitative analysis of garlic price data based on ArcGIS technology.The specific analysis process is to collect prices of garlic market from 2015 to 2017 in different regions of Shandong Province,using the Moran's Index to obtain monthly Moran indicators are positive,so as to analyze the overall positive relationship between garlic prices;then using the geostatistical analysis tool in ArcGIS to draw a spatial distribution Grid diagram,it was found that the price of garlic has a significant geographical agglomeration phenomenon and showed a multi-center distribution trend.The results showed that the agglomeration centers are Jining,Dongying,Qingdao,and Yantai.At the end of the article,according to the research results,constructive suggestions were made for the regulation of garlic price.Using Moran’s Index and geostatistical analysis tools to analyze the data of garlic price,which made up for the lack of position correlation in the traditional analysis methods and more intuitively and effectively reflected the trend of garlic price from low to high from west to east in Shandong Province and showed a pattern of circular distribution.

Electricity Pricing Policy Should Serve Macro-Economic Control

The National Development and Reform Commission beefed up its efforts to promote the work of electricity price reform in 2004. It took measures in aspects of easing price contradictions, tentatively implementing discriminated price and time-of-use price and issuing a policy on the linkage of coal and electricity prices and price administration. In 2005 the basic thinking of the Commission's electricity price reform is to actively advance the pilot work of price reform,carry out the reform of transmission and distribution price, enlarge the scope of pilot work of large consumer's direct purchase, simplify sales price structure and bring about the linkage of coal and electricity prices.

Pricing Mechanism in Power Market Construction

The reform on electricity pricing mechanism is a critical problem in power market construction in China, and is in mutual supplementation and promotion with the latter. In particular, the pricing mechanism for electricity fed into network and that for electricity transmission and distribution as well as the relationship between coal and electricity prices, etc. have to be studied in depth. This paper presents several solutions and suggestions to these problems.

A Three-Stage Stochastic Dynamic Pricing Game Model Affected by New Products into the Market

In real-life marketing, a common phenomenon is that the prices of current product will have been cut down even the new product has not gone into market yet. Thus, it is very important for merchant to set the strategy which can make the excepted revenue maximum. So, this paper constructs a three-stage stochastic dynamic pricing game model for analyzing the influence of the uncertainty of entry timing of the new products on pricing of products being sold. By analyzing of the pricing strategy, there are big differences in the predictions of new product going into market between merchant and customers;the merchant will adopt cutting price for promotion strategy to reduce negative influence of the new products on the demand of the products sold now. Otherwise, the merchant will adopt the strategy of maximizing current period’s profit.

Research on Sales Strategy Based on Supermarket Pipeline Data

“Low profit and high sales” is a strategy to increase sales volume by reducing the profit of unit goods, so that businesses can gain more profits. For flexible goods, price reduction can increase the total revenue, but when the goods are lack of flexibility, price reduction will reduce the total revenue. In this paper, according to the sales data provided by a supermarket, we preprocess the data, establish appropriate indicators to measure the daily discount strength of the mall, and establish a mathematical model between the discount strength, sales and profit margin. Through these models, we found that meager profits do bring up sales, but too low discounts can also hurt total profits. In addition, when shopping malls implement discount promotions, they will also bring some negative effects, and we give some suggestions for this.

Do the RMB exchange rate and global commodity prices have asymmetric or symmetric effects on China’s stock prices?

With the rapid expansion of the RMB exchange rate’s floating range,the effects of the RMB exchange rate and global commodity price changes on China’s stock prices are likely to increase.This study uses both auto regressive distributed lag(ARDL)and nonlinear ARDL(NARDL)approaches to explore the symmetric and asymmetric effects of the RMB exchange rate and global commodity prices on China’s stock prices.Our findings show that without considering the critical variable of global commodity prices,there is no cointegration relationship between the RMB exchange rate and China’s stock prices,and the coefficient of the RMB exchange rate is not statistically significant.However,when we introduce global commodity prices into the NARDL model,the result shows that the RMB exchange rate has a negative effect on China’s stock prices,that there indeed exists a long-run cointegration relationship among the RMB exchange rate,global commodity prices,and stock prices in the NARDL model,and that global commodity price changes have an asymmetric effect on China’s stock prices in the long run.Specifically,China’s stock prices are more sensitive to increases than decreases in global commodity prices.Thus,increases in global commodity prices cause China’s stock prices to decline sharply.In contrast,the same magnitude of decline in global commodity prices induces a smaller increase in China’s stock prices.

China’s Price System Jeopardizes its Grain Reserves

2008 is a year of bumper harvest in summer grain across China. The failure of numerous state-owned grain depots to purchase grain in times of bumper harvest, however, directly threatens grain reserve security and state control over grain prices in the upcoming year. An important factor underpinning the difficulty of state grain depots to purchase grain is the unwillingness of farmers to sell grain due to the excess of the current market price over the government "protected price" aimed at preventing cheap grain from harming farmers. When grassroots grain depots find themselves in trouble, foreign capital stealthily moves in by taking advantage of this situation. To fulfill grain storage tasks and receive various state subsidies, some state-owned grain depots have no alternative but to surreptitiously raise the purchase price. By contrast, some not so courageous state-owned grain depots can only borrow money to finance the purchase of commodity grain at market prices and subsequently figure out a way to pay back such loans. Behind such distorted grain purchase behavior lies a rough and rugged history of grain price reform in China.