题目如下:
A European Call option on a non-dividend-paying stock has delta = 0.55, gamma = 0.3, vega = 0.1. Theta is unknown. Interest rate = 4%. Total portfolio = $25,000. If strike price and time to maturity are the same, what is:
Vega of a European put option?
If delta and gamma of the portfolio are zero, what is theta?
Theta应该怎么算啊?跪求了.....