Quote from jimclark:
What is the difference? is the premium only the difference?
If I think price will go down...why can't I just sell CALLS(short) instead of buying PUTs?
Thanks.
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I had a similar question before and the best explanation i got was recently after having read the Market Wizards by Jack Schwager (a must read for every aspiring trader IMHO) at the appendix it states:
"Whereas the buyer of a call or put has limited risk and unlimited potential gain, the reverse is true for the seller. The option seller (often called the writer) receives the dollar value of the premium in return for undertaking the obligation to assume an opposite position at the strike price if an option is exercised."
"Some novices have trouble understanding why a trader would not always prefer the buy side of the option (call or put, depending on market opinion), since such a trade has unlimited potential and limited risk. Such confusion reflects the
failure to take probability into account. Although the option seller's theoretical risk is unlimited, the price levels that have the greatest probability of occurrence (i.e., prices in the vicinity of the market price when the option trade occurs) would result in a net gain to the option seller. Roughly speaking,
the option buyer accepts a large probability of a small loss in return for a small probability of a large gain, whereas the option seller accepts a small probability of a large loss in exchange for a large probability of a small gain. In an efficient market, neither the consistent option buyer nor the consistent option seller should have any significant advantage over the long run."
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I think that clearly explains the difference as at first it seems suicide to sell calls because of the unlimited risk (same as shorting a stock outright)and limited profit potential. But as one learns to think in probabilities, it doesn't seem so bad. In any event, some form of risk management must be in place so assuming the stock did go against you a certain amount you should cut your losses short. Again, easier said than done.