Figure 1. The stock price trend of Apple Inc. 
As shown above, Apple Inc’s stock price had small 
reduction from Jun. 1st, 2022, to Jun.28th,2022, from 
$148.71 to $138.44. there was some minor volatility 
as  Apple's  share  price  declined  during  the  study 
period. 
2.2  Method 
The  Black-Scholes  formula  is  used  as  a  model  for 
valuing European or American call and put options on 
a non-dividend paying stock. In option pricing theory, 
the  Black-Scholes  equation  is  one  of  the  most 
effective  models  for  pricing  options  (Mehrdoust, 
2014). Black Scholes model take into account the risk 
factor of the underlying stock, the strike price of the 
option  contract,  the  initial  stock  price  and  the  time 
value  of  money,  which  are  all  significant  factors, 
while  pricing  each  option  contract.  Its 
comprehensiveness  and  completeness  also  enhances 
its accuracy while computing different option prices. 
All options have limited downside and rely on price 
volatility for upside, thus a rise in volatility raises the 
value of both calls and puts (Yacine, 2003). However, 
the  Black  Scholes  model,  similar  to  other  option 
pricing models, is  not a perfect one  as well. In fact, 
there are some unrealistic assumptions that the Black 
Scholes model makes in order for its convenience of 
computation and conciseness. First, the Black Scholes 
model  assumes  that  volatility  of  the  stock  and  the 
market’s risk-free rate are all constant throughout the 
whole maturity time, which is not true in the real case. 
Second, the Black Scholes model also assumes that no 
option  could  be  exercised  before  the  maturity  time, 
which makes it only effective while pricing European 
option  contracts.  Third,  the  Black  Scholes  assumed 
that the market is a frictionless one, which means there 
would not exist any transactional costs while trading 
these  financial  derivatives,  which  is also unrealistic, 
too. Last but not least, although all these up-mentioned 
assumptions  might  affect  the  accuracy  of  the  Black 
Scholes model, we could not deny that it is still one of 
the  most  common and  conservative  way  for pricing 
European option contracts. 
Options Spread is a trading strategy for options in 
the  financial  market  that  entails  taking  opposite 
directional positions in the price of a pair of options 
belonging  to  the  same  asset class  but  with different 
strike  prices  and  expiry  dates.  A  spread  position 
involves  two  options  with  distinct  strike  prices  and 
expiry dates (Abhilash, 2021). The hedging strategy is 
completed  with  two  steps  in  the  research  as  below. 
First, the  implied volatility of the  stock is  calibrated 
with the price of the stock and that of ten options as 
selected,  on  the  stock  using  Black  Scholes  model. 
Second,  applying  the  implied volatility  calculated,  a 
hedging strategy is constituted for a chosen option on 
the stock.   
Following on, the implied volatility utilized in the 
Black-Scholes model is an estimated value estimated 
by  calculating  the  market  stock  prices’  standard 
deviation  or  other  estimating  and  forecasting 
techniques  such  as  maximum  likelihood  estimation, 
moment  estimation,  generalized  linear  model, 
Bayesian point estimation. In our study, we decided to 
estimate  the  volatility  in  two  different  ways:  the 
traditional market stock prices’ standard deviation and 
minimizing the difference between real market option 
price and Black-Scholes price calculated utilizing the 
Black-Scholes  formula.  The  whole  pricing  process 
stars as the following. First, we choose the 2022 June 
1st AAPL open price as our initial stock price S (0). 
Second, we choose five different call options and put 
120
125
130
135
140
145
150
6,01 6,06 6,09 6,14 6,17 6,23 6,28
Appe Inc.