Investment Portfolio Models Based On Liquidity And Demonstration

The portfolio is always an important problem in the financial field.Due to the complexity of the financial market and the influence of environmental factors,the liquidity of securities has become a factor that can not be ignored in the investment.But at present there are not many researches on the integration of liquidity into portfolio decision models which needs to be perfected.Considering liquidity,transaction costs and other factors in portfolio decision models,the main research results are shown as follows:(1)Liquidity,which is considered to determine the investment proportion constraints based on positive correlation,is an important factor that cannot be neglected in the investment portfolio.Aiming at the influence of human psychological satisfaction on investment,logarithmic functions are constructed to express the investor’s satisfaction with investment income and risk.Then a portfolio model based on investor satisfaction is established under the investment proportion and transaction costs constraints.Finally,an example is given to illustrate the validity of the model.(2)According to the probability average in fuzzy theory,the possibility volatility difference of fuzzy income on securities is defined which is used to measure portfolio risk.Under the constraints of investment proportion that determined by liquidity and transaction costs,a fuzzy portfolio model based on liquidity and possibility volatility difference is established.Finally,an example is given to illustrate the validity of the model.(3)Define the expected value of intuitionistic fuzzy number based on the meaning of membership degree and geometric gravity center,which is be used to remove fuzzification of the key indicators that fuzzy income,uncertain risk and liquidity of securities.Under the constraints of investment proportion that determined by liquidity,establish an intuitionistic fuzzy portfolio model that considers the income,risk and liquidity which are described through intuitionistic fuzzy decision information.Finally,an example is given to illustrate the validity of the model.