Quote from DiagonalSpread:
Thank you for the entry prices - Does your system pick these 10 trades independent of each other or does it use expected correlations to make it profitable? ( sorry for all the questions i've recently been using a lot of ratio spreads and have had really good luck with them but yours seem to be more complex and I'd like to understand exactly what your doing)
Quote from oldnemesis:
' My system scans for positive expectancy spreads '
How are you computing expectancy??
I assume that moves in the future are equally likely to the ones in the past. Nothing to do with lognormal distribution and standard deviation. If market moved up 10% in 10 days in the past, I assume I might move 10% in the next 10 days. That means about 0.957% a day. I also assume that opposite move is equally likely - 0.957% down a day for next 10 days. I look at last 10 years and build a list of possible moves. Out of those moves I calculate which spreads give me profit factor bigger than 1.0. I like spreads that give historical profit factor of at least 2.0. Out of those spreads I choose the ones with high probability, decent average win / average loss and reasonable median result.Quote from oldnemesis:
SO....
You are assuming a log normal distribution, computing the standard deviation and then what??
Sorry, I don't know what you mean by 'Z shaped'Your spreads have a Z shaped continuous P/L graph. How do you get expectation out of it so you can find those with positive expectations??
Also, since options are priced by market makers using the same assumptions shouldn't most expectations equal zero or less??