I learned how to price ana European call option using this video lecture. The considered case is very simple. The call option gives the right to buy 100 Euros for 100 Dollars in one month from now. Now theThe 100 Euros cost 100 Dollars now but in 1 month they will cost either 105 Euros or 95 Euros (the probability of both prices is the same). The proposed strategy is the following: We, as the option seller, sell the option for 2\$2.97 Dollars, then we take a 47borrow \$47.03 Dollars loan from the bank (the interest rate of the return is 1% for 1 month). We use these 50 Dollars\$50 (47.03 + 2.97) to buy 50 Euros. This procedure guarantees that in one month we will not lose/earn anything independently onof the price of the Euros.
Why do we need to take a loanborrow? To me it seems as nonto not be beneficial operation. We take 47\$47.03 dollars and we need to return 47\$47.5 Dollars50. So, in total we loose 47 centslose \$0.47 independently onof the price of the Euro.
I would propose another strategy. We use our own money (47\$47.03 Dollars) to buy the 50 Euros (we also use 2\$2.97 Dollars paidto pay for the option). In this case, in one month, we shoulddo not return anythingneed to the bankrepay any loan. As a result, we can earn 47 cent\$0.47 independently onof the price of the Euros.
You could say that the second strategy is worse because, if we pay our own 47\$47.03 Dollars, we cannot use this money for a whole month. SoHence, the money will not earn an interest. But I do not agree since we can consider this as an investment. We use 47\$47.03 Dollars, to earn 47\$47 in one month. So, the interest rate is 1%. You could say, that the bank providelending provides the same interest rate, so we could use the first strategy, and then use the saved 47\$47.03 Dollars to putlend them into the bankout and earn the same 47 cents. OK\$0. Here I would agree with you47.
But what if we use the second strategy (we take no loan to buy the 50 Euros).? Since we do not need to return a larger amount of moneys to the bankrepay more money, we can make our option cheaper. It could cost 2\$2.50 instead of 2\$2.97. So, ifIf we set the price equal to 2\$2.60, we will get 10 cent\$0.10 from every option (independently onof the price of the Euro). And sinceSince our option is cheaper than the options provided by other companies, we can sell a lot of options. Yes, we willWe may not earn 47\$0.47 cents from the option, we will earn only 10 cents (about 5 times less)\$0.10 but may be we will sell 10 times more options. Is this possible?