Displaying 20 results from an estimated 396 matches for "portfolios".
Did you mean:
portfolio
2006 Mar 03
5
avoiding nil object error?
I''m a total Rails newbie and i''ve been struggling for hours today
with one (prolly very silly) problem:
I have a table portfolios that has many images:
class Portfolio < ActiveRecord::Base
has_many :images
end
class Image < ActiveRecord::Base
belongs_to :portfolios
end
In the controller i define a list of active portfolios:
@active_portfolios = Portfolio.find_all_by_is_active("1")
In the view i render the...
2011 Sep 15
1
portfolio, portfolio.optim function not found
Hello,
After installing and loading the package "portfolio", I tried to run the
example code provided, and it would not run.
this is the link:
http://rss.acs.unt.edu/Rdoc/library/tseries/html/portfolio.optim.html
this is the example code, as found at the link:
x <- rnorm(1000)
dim(x) <- c(500,2)
res <- portfolio.optim(x)
res$pw
the error I get is:
Error: could not find
2005 Jan 13
1
how to use solve.QP
At the risk of ridicule for my deficient linear algebra skills, I ask
for help using the solve.QP function to do portfolio optimization. I
am trying to following a textbook example and need help converting the
problem into the format required by solve.QP. Below is my sample code
if anyone is willing to go through it. This problem will not solve
because it is not set up properly. I hope I
2011 Jul 07
2
elimination duplicate elements sampling!
Hi everyone!
I have a data frame with 1112 time series and I am going to randomly
sampling r samples for z times to compose different portfolio size(r
securities portfolio). As for r=2 and z=10000,that's:
z=10000
A=seq(1:1112)
x1=sample(A,z,replace =TRUE)
x2=sample(A,z,replace =TRUE)
M=cbind(x1,x2) # combination of 2 series
Because in a portfolio with x1[i]=x2[i],(i=1,2,...,10000) means a 1
2012 Feb 15
2
Control number of assets in resulting portfolio with optimizations using package fPortfolio
Dear All,
I am using package fPortfolio to run minimum variance portfolio
optimizations in R. I already know how to set portfolioSpecs, portfolio
objects and constraints. Unfortunately I am not able to set the following
type of constraints.
I have a timeSeries object with returns data for roughly 1.5k assets for 261
subperiods (workingdays) and want to compute the global minimum variance
portfolio, considering following const...
2012 Jul 23
1
Help with Portfolio Optmization
Hi,
I need some help with Portfolio Optimization problem. I am trying to find
the minimum variance portfolio subjected to constraints on weights like
/x1< w1 <x2
x3< w2 <x4</i>
I need help with solving for the minimum variance portfolio as solve.QP
doesn't allow me to specify the lower boundaries.
Thanks
Mahesh
--
View this message in context:
2008 Sep 03
1
portfolio.optim and assets with weigth equals to zero...
Hello.
I don't understand a particular output of portfolio.optim (tseries).
I have 4 assets and the portfolio.optim returns an asset with weight equals
to zero.
If I do a portfolio.optim with 3 assets, without the asset with weight
equals to zero,
it returns a completely different result.
That's I would expected the same weights as the run with 4 assets.
Below the code.
Thanks in
2008 Jul 21
1
portfolio optimization problem - use R
How to use R to solve the optimisaton problem
Minimize:
?*w^T*omega*w+mu^T*w+c^T(w-w0) for w>w0 long position
?*w^T*omega*w+mu^T*w-c^T(w-w0) for w<w0 short position
W: is the update weight of portfolio
Wo is the initial weight of portfolio
Omega is the variance covariance matrix
mu is the vector of return rate of stocks in the portfolio
C is the vector coefficient of transaction cost
2008 Nov 18
2
anyone familiar with this error?
[whit at linuxsvr R.packages]$ sudo R CMD INSTALL portfolio.construction
* Installing to library '/usr/local/lib64/R/library'
* Installing *source* package 'portfolio.construction' ...
** R
** preparing package for lazy loading
Loading required package: fts
Loading required package: quadprog
Loading required package: Rexcelpoi
terminate called after throwing an instance of
2006 Feb 09
6
troubleshooting an observe_field
Hi,
I''ve got a live_search field in a partial that is on several different
pages. On all pages, except 1, it works fine. On the page it doesn''t work
on, it seems it never executes it action.
Here''s my observe_field code inside the partial:
<h1><label for="searchtext">Live Search:</label></h1>
<%= text_field_tag :searchtext
2006 Mar 06
0
New package 'portfolio'
We would like to announce the availability of the 'portfolio' package
in R for analysing equity portfolios. Version 0.2-0 is now available
on CRAN. To take a look, you can:
> install.packages("portfolio")
...
> vignette("portfolio")
and play around. Those who would just like to check out an
introduction can simply look at:
http://www.kanecap.com/R/portfolio/portfolio.pdf...
2006 Mar 06
0
New package 'portfolio'
We would like to announce the availability of the 'portfolio' package
in R for analysing equity portfolios. Version 0.2-0 is now available
on CRAN. To take a look, you can:
> install.packages("portfolio")
...
> vignette("portfolio")
and play around. Those who would just like to check out an
introduction can simply look at:
http://www.kanecap.com/R/portfolio/portfolio.pdf...
2012 Sep 04
0
Calculate a minimum-variance portfolio with fPortfolio
...# Constraints
box.1 <- paste0("minW[1:nAssets] = ", 0)
box.2 <- paste0("maxW[1:nAssets] = ", 0.10)
box.3 <- "maxsumW[1:nAssets] = 1"
box.4 <- "minsumW[1:nAssets] = 1"
boxConstraints <- c(box.1, box.2, box.3, box.4)
# Portfolio Specs
Spec <- portfolioSpec()
# Calculate MinVar Portfolio
minvar <- minvariancePortfolio(
data = data,
spec = Spec,
constraints = boxConstraints)
5. Thanks a lot for your help!
Markus Douglas, Jr.
--
View this message in context: http://r.789695.n4.nabble.com/Calculate-a-minimum-variance-portfolio...
2011 Jan 07
1
Currency return calculations
Dear sir, I am extremely sorry for messing up the logic
asking for help w.r.t. my earlier mails
I have tried to explain below what I am looking for.
I have a database (say, currency_rates) storing datewise
currency exchange rates with some base currency XYZ.
currency_rates <- data.frame(date =
c("12/31/2010", "12/30/2010", "12/29/2010",
2012 Jan 13
1
Portfolio Optimization
Hi,
I'm an R newbie and I've been struggling with a optimization problem for
the past couple of days now.
Here's the problem - I have a matrix of expected payouts from different
stock option strategies. Each column in my matrix represents a different
stock and each row represents the return to the strategy given a certain
market move. So the rows are not a time series of percentage
2012 Oct 12
1
error msg using na.approx "x and index must have the same length"
Below I have written out some simplified data from my dataset. My goal is
to interpolate Price based on timestamp. Therefore the closer a Price is in
time to another price, the more like that price it will be. I want the
interpolations for each St and not across St (St is a factor with levels
A, B, and C). Unfortunately, I get error messages from code I wrote.
In the end only IDs 10 and 14 will
2006 Nov 10
1
Value at Risk historical simulation
Hi
Has someone got a package/script at hand to do a historical simulation
to calculate the Value at Risk?
If your not sure what Historical Simulation is:
In simple terms, Historical Simulation (HS) is just taking sample
percentiles over a moving sample. Suppose we want to use HS to predict
a portfolio's Value-at-Risk at a confidence level of 99 percent and
the window size is chosen to be 250
2012 Jul 23
2
Bug in my code (finding nonzero min)
...ney, data3[,5] are their cost, so for each
portfolio, i.e. the rows of new.set I have the option to purchase another
stock at a cost listed in the rows of variable remain. Obvisouly the
cheapest stock needs to have a cost>0 in order for me to be allowed to buy
it. My code is intended to weed out portfolios where I could have bought
another stock, by taking budget-portfolio cost - (cheapest available stock)
and subsetting new.set when this is negative, i.e. buying the cheapest
available stock puts me over budget. My problem is that my code is still
allowing examples like the following budget of 10, po...
2006 Oct 23
0
New version of 'portfolio' and new related packages
A new version of package 'portfolio' is now available on CRAN. Also
available are new packages 'backtest', for basic spread-based
hypothesis testing, and 'portfolioSim', a general framework for
portfolio simulation.
Last March we wrote R-packages regarding our desire to build a suite
of tools for portfolio analytics in R:
https://stat.ethz.ch/pipermail/r-packages/2006/000171.html
Since then we've made progress by improving 'portfolio' and add...
2003 May 18
0
POP Portfolio Optimizer
Burns Statistics has just released its POP Portfolio Optimizer, which
is available for a license fee. This has an interface designed to run
under either S-PLUS or R.
In addition to portfolio selection and asset allocation, there is
functionality
to generate random portfolios, and to estimate statistical factor models.
The website includes a new working paper on the best approach to
using statistical factor models to optimize portfolios with a benchmark.
Details are on http://www.burns-stat.com/
Patrick Burns
Burns Statistics
patrick at burns-stat.com
+44 (0)20 8525...