340 likes | 435 Views
IWIF-II. Model of Financial Market : Insights and its Possible Application. C. H. Yeung 1 , K. Y. Michael Wong 1 . Y. C. Zhang 1,2. 1 Department of Physics, the Hong Kong University of Science and Technology, Hong Kong, China
E N D
IWIF-II Model of Financial Market :Insights and its Possible Application C. H. Yeung1, K. Y. Michael Wong1. Y. C. Zhang1,2 1Department of Physics, the Hong Kong University of Science and Technology, Hong Kong, China 2Institut de Physique Théorique, Université de Fribourg, 1700 Fribourg, Switzerland www.swingtum.com/institute/IWIF
Outline • Introduction Our model (Wealth Game) VS Minority Game ? • Price Sensitivity and Market Impact – Phase Diagram of final states and wealth • Market Makers, Transaction Cost and Evolutions – Positive gain for agents and market makers • Application on real data: Trading with Hang Seng Index • Conclusion www.swingtum.com/institute/IWIF
Introduction • Minority Game (MG) – The model by D. Challet and Y. C. Zhang in 1997 • Successful and simple model of Financial Market which states that the minority choices will win • One of the main concern for investors: negative-sum (MG) VS positive-sum (Real market) ? www.swingtum.com/institute/IWIF
To include more realistic aspects … • What modifications are we making? • What important aspects of real markets should be added to capture basic features? • Negative sum? Positive sum? Zero sum? • Can we apply these financial models on real financial data ? www.swingtum.com/institute/IWIF
1. What modificationsare we making? www.swingtum.com/institute/IWIF
Individual actions Price changes Collective actions The Model • N agents • Each agent makes decision from his/her best strategy (higher virtual payoff) www.swingtum.com/institute/IWIF
The Strategy • +1/ -1/ 0, buy/ sell/ hold decisions (different from MG) • Max. Allowed PositionK www.swingtum.com/institute/IWIF
Remark : For MG, Wealth = Cash + Stock Values in hand No. of stock in hand, Position www.swingtum.com/institute/IWIF
2. Whatimportant aspects of real markets should be added to capture basic features? (1) Price sensitivity & (2) Market impact www.swingtum.com/institute/IWIF
Price rises!! Collective Actions What are price sensitivity and market impact? • Price Sensitivity • Sensitivity of stock price on agent’s collective actions • Define γ : Individual Actions Price movement = (Collective actions)γ www.swingtum.com/institute/IWIF
Market Impact !! Synchronized Actions !! • Market Impact • The impact of synchronized decisions from peer investors during transaction • Define β Transaction price = Current price +β(Synchronized price movement) www.swingtum.com/institute/IWIF
(1) Price sensitivity γ Price movement = (Collective actions)γ (2) Market Impact β Transaction price = Current price +β(Synchronized price movement) These 2 aspects we would like to put in the model !! www.swingtum.com/institute/IWIF
Collective actions !! Price Sensitivity!! Market Impact !! • Decision of agent ai(t) = +1, 0, -1 • Real Price: • Transaction Price PT(t) = Price in between P(t+1) and P(t) www.swingtum.com/institute/IWIF
Negative Positive Results Final State of the system Agents’ Wealth www.swingtum.com/institute/IWIF 3 phases have positive wealth ???
Irregular phase ?? Trendsetter phase ?? Phase Diagram of Final State Mixture phase ?? Arbitrageurs phase ?? www.swingtum.com/institute/IWIF
sell! Buy! For β≤ 0.5⇒ Period-2 cycle for P(t) !? Arbitrageurs phase Gain!! Too unrealistic!! www.swingtum.com/institute/IWIF
Trendsetter state What are they doing? • Periodic with characteristic pattern • Period much longer than period 2 !! VS Arbitrageur state www.swingtum.com/institute/IWIF
Trend setters (winners) Trend followers (winners) Late followers (losers) Start to sell !! (Set up the downward trend) Follow the trend !! I was late... Trendsetter state Depend on strategies, eg: ↑↑↓ buy/sell/hold ↑↓↓ buy/sell/hold …. We didn’t teach them to set up and follow trend !! But they do it !!! www.swingtum.com/institute/IWIF
Too periodic! Period 2 Unrealistic! or Unrealistic! www.swingtum.com/institute/IWIF
Negative Positive What’s the interpretations?The real market is possibly…… Agent’s wealth www.swingtum.com/institute/IWIF Possible parameters of real market !!
3.Negative sum? Positive sum? Zero sum? www.swingtum.com/institute/IWIF
Positive-sum?Where does the money come from? • Note: Supply and Demand is not balanced in this model • There is a Market Maker behind the game • Market Maker is clearing the extra supply and demand (doing opposite as the actual agents do) • So, agents gain, Market Maker loses • All together ~> zero sum www.swingtum.com/institute/IWIF Market Maker ?
No Market Maker, supply and demand have to be balanced ~> when one agent is holding a buying position, someone else must be holding a selling position ~> zero-sum for agents • Can both Agents and Market Maker gain? • Transaction cost + evolution of agents (agents losing money are leaving the market) www.swingtum.com/institute/IWIF
Transaction Cost (% of P(t))+ Evolution Positive gain for Investors and Market maker !! ~> Participation incentives www.swingtum.com/institute/IWIF
4. Can we apply these financial models onreal financial data ? www.swingtum.com/institute/IWIF
Application on real data:Hang Seng Index (HSI) • To convince ourselves that the model share similarities with real market, we test the applicability of the model on HSI • Real HSI as external signals, stock price in the model • Agents are given a certain amount of initial wealth, for initial investment • Wealth dependence maximum position K(t) = Wealth(t) / Price(t) www.swingtum.com/institute/IWIF
Results (HSI from 1987 – 2007) Best 3 among 10000 Agents x 17 times HSI x 7.5 times 5 random agents www.swingtum.com/institute/IWIF
Initially, w(1987)/P(1987) = 5 Wealth grows slower than inflation Wealth grows faster than inflation www.swingtum.com/institute/IWIF
Comparison with other models- % of gaining agents ≈ 11% of agents in this model Beat HSI inflation in this 20 years www.swingtum.com/institute/IWIF
Wealth Game Minority Game • Wealth Game has the largest % of gaining agents • But for the best investor……. x 25 times x 17 times x 7.5 times x 7.5 times Minority Game has more outstanding best investor ! www.swingtum.com/institute/IWIF
Difference in wealth counting….. Wealth Game Minority Game VS with Trend following? • Positive sign VS negative sign • Position dependence VS Single bid • dependence • 3.Small time lag Longer memory www.swingtum.com/institute/IWIF
Wealth Game Vs Minority Game Another similar test : Wealth independent Max Pos. with w(0) = 0 Best investors are not as rich as MG, but most are gaining Best investors are more outstanding Most agents are losing www.swingtum.com/institute/IWIF
Conclusion • Behaviors resembling real investors emerge naturally form this simple model • Possible values of γ and β (price sensitivity and market impact) in real market can be conjectured form the phase diagrams (irregular phase with positive wealth) • Wide participation incentives: positive sum for both existing agents and market maker • The model is tested by using real HSI Wealth Game: better average performance Minority game: more outstanding best agents www.swingtum.com/institute/IWIF
Thank You!!Questions & Answers Session Acknowledgement: Supported by the Research Grant Council of Hong Kong(DAG05/06.SC36 and HKUST603606)" All cartoon figures from coolclip.com www.swingtum.com/institute/IWIF