thx again........
that page was helpful.. i will probably go there in next few days and ask some questions......
cliff notes in bold
i do have semi-basic question........... a person provided an answer there and it look interesting. i used it for portfolio split between SPY and TLT.
i did have a glaring question if i was going to use it for 3 asset portfolio.. say SPY, TLT, and gold (GLD)
my excel usage of his formula for covariance between stocks and portfolio D (say 50/30/20) makes use of 1) stock variance, 2) stock/bond correlation, 3) stock/gold correlation... but NOT bond/gold correlation......... the standard deviation of the portfolio would use this however.
this is more a basic probability question right now... can i derive bond/gold correlation from those other 3 numbers? i would have thought "no"
thanks again
....... there may be other solutions later in the discussion i haven't got to