3.Strategies of the Options.ppt

（2） Short Strangles（等量空头异价对敲 ） The portfolio of selling a Call and a Put option with the same expiries , but two different strike prices Xp Xc is called “ Short Strangle ” . At the expiration date T , if the price of the asset is ST , the profit function for this Short Strangle will be : Two equilubrium points： the maximal loss ( 最大亏损值) ： the maximal profit ( 最大盈余值 ) : unlimited , if ST tends to infinite if ST goes to zero . Similar with Short Straddle , benefited in the middle ；the speculator suppose the price of the asset will not change a lot from its spot price , but he is not sure the price is increasing or decreasing a little But ther is a difference between Stragles and Straddles : the premiums for the Short Strangle are c + p , this amount of money is less than that ( c + p* ) for the Short Straddle ; however , the speculator with the Strangle can’t benefit in a broader interval : 3 . Strips and Straps (不等量同价对敲 ) (1) . Strips（少看涨、多看跌的多头同价对敲 ） The portfolio of buying one Call and two Puts options with the same expiries and the same strike prices is called “ Strip ” . At the expiration date T , if the price of the asset is ST , the profit function for this Strip will be : Two equilubrium points : the maximal loss the maximal profit： unlimited , if ST tends to infinite , if ST goes to zero . but he is not sure the price is increasing or decreasing with a large scale . Benefited from both ends ；the speculator supposes the price of the asset will have a great change from its spot price , and the possibility of the decrease is larger than the increase ; (2) Straps（多看涨、少看跌的多头同价对敲 ） The portfolio of buying two Call and one Put option with the same expiries and the same Strike prices is called “ Strap ” . At the expiration date T , if the pric