Dear All,
I am a bit new at this and I am currently trying to optimize a portfolio of
19 assets with portfolio.optimize from the *tseries *package and I have a
few questions:


   - I have a .csv file of 19 assets, with *daily *returns ranging from
   05/1999 to 05/1999. Is it enough if I just transform my .csv file is a ts
   object using read.ts(file="xxxx.csv", head=TRUE, sep=",") without specifying
   other parameters such as start=..., or end=... ? Does it make any difference
   in the final result?
   - Also, considering I have a header, should I put skip=1 or skip=0?
   - Also, is the risk free rate understood as a annualized?
   - Last, when I input the following data in portfolio.optim,

*Optim<-portfolio.optim(Rets, pm=mean(Rets), riskless=FALSE, shorts=FALSE,
rf=0.05, reslow=c(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0),
reshigh=c(1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1), covmat=cov(Rets))*

I get the following error message
*Error in solve.QP(Dmat, dvec, Amat, bvec = b0, meq = 2) : *
*  matrix D in quadratic function is not positive definite!*
*
*
How can I solve this problem?
Thank you very much for you help - I just can't understand why I get an
error message..

Lara

-- 
Lara Shocron
lara.shocron@gmail.com
+ 852 9765 4623
+ 33 6 12 89 97 08

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