Dmo,
Another way to look at negative interest rate is that you can't really lend and borrow money at the same rate as assume in the black and scholes world, in the binomial world, in the trinomial world...and generally written in books.
The second point is that sometimes you have to pay annual fees to your broker. Hence, as long as you hold a position, or don't, the fact that your account is opened leads to costs.
Another way to look at a delta >1 is this one.
Imagine you're on a perishable asset, like tomatos. As long as you hold a real position on tomatos, you need a warehouse. This is a storage cost. Assume that cash price stays fixed. How do you think future on that commodity would react with time ? Hence for a call on that future ?
About the skew, it was just in response to your statement.
Dmo, you are a clever guy. Please open your mind. Nothing is a given especially on derivatives. And the correlation you talk about between VIX and SPX is correlation between VIX and SPX. Not between volatility(ies) and SPX. Of course you will generally have a behaviour like you state for a very short term volatility. This is one month volty, or two months volty. It can't be generalized for every volty behaviours.
Tomorrow, assume there is a market collapse. Assume a 6% down move. A guy clever as you are can't really think that a 10 years option volatility on SPX would be hurt by something like that. I hope you don't. I bet you don't. I'm sure you don"t
.
Another way to look at negative interest rate is that you can't really lend and borrow money at the same rate as assume in the black and scholes world, in the binomial world, in the trinomial world...and generally written in books.
The second point is that sometimes you have to pay annual fees to your broker. Hence, as long as you hold a position, or don't, the fact that your account is opened leads to costs.
Another way to look at a delta >1 is this one.
Imagine you're on a perishable asset, like tomatos. As long as you hold a real position on tomatos, you need a warehouse. This is a storage cost. Assume that cash price stays fixed. How do you think future on that commodity would react with time ? Hence for a call on that future ?
About the skew, it was just in response to your statement.
Dmo, you are a clever guy. Please open your mind. Nothing is a given especially on derivatives. And the correlation you talk about between VIX and SPX is correlation between VIX and SPX. Not between volatility(ies) and SPX. Of course you will generally have a behaviour like you state for a very short term volatility. This is one month volty, or two months volty. It can't be generalized for every volty behaviours.
Tomorrow, assume there is a market collapse. Assume a 6% down move. A guy clever as you are can't really think that a 10 years option volatility on SPX would be hurt by something like that. I hope you don't. I bet you don't. I'm sure you don"t
.
negative correlation between IV and SPX, please try to take a look at what is going on with S&P DEC10 and DEC11 implied volatility options. I'm sure your obstinacy won't last