Displaying 20 results from an estimated 10000 matches similar to: "Non-linear constraints under Markowitz"
2002 Aug 21
4
Quadratic optimization problem
I hope that someone can help me with the following question:
I would like to solve the Markowitz optimization problem WITH short-sale
constraints.
Maybe a procedure to solve a quadratic optimization problem with convex
constraints and positive variables is already implemented in R?
Thank you very much,
edg
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r-help
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
2004 Aug 09
4
linear constraint optim with bounds/reparametrization
Hello All,
I would like to optimize a (log-)likelihood function subject to a number of
linear constraints between parameters. These constraints are equality
constraints of the form A%*%theta=c, ie (1,1) %*% 0.8,0.2)^t = 1 meaning
that these parameters should sum to one. Moreover, there are bounds on the
individual parameters, in most cases that I am considering parameters are
bound between zero
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
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
2018 May 03
2
adding overall constraint in optim()
Thanks Bert. But everyone on that forum wants to use finance tools rather than general optimization stuff! And I am not optimizing a traditional Markowitz mean-variance problem. Plus, smarter people here. :-)
> On May 3, 2018, at 3:01 PM, Bert Gunter <bgunter.4567 at gmail.com> wrote:
>
> You can't -- at least as I read the docs for ?optim (but I'm pretty
> ignorant
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
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 =
2018 May 04
0
adding overall constraint in optim()
On Thu, May 3, 2018 at 2:03 PM, Michael Ashton
<m.ashton at enduringinvestments.com> wrote:
> Thanks Bert. But everyone on that forum wants to use finance tools rather than general optimization stuff! And I am not optimizing a traditional Markowitz mean-variance problem. Plus, smarter people here. :-)
>
I'm very confused by these statements. Most of the "finance tools"
1999 Nov 27
1
portfolio.optim.default, Packages tseries quadprog (PR#348)
Full_Name: Ansgar Steland
Version: 0.90.0
OS: Linux 6.1 FreeBSD 3.2
Submission from: (NULL) (62.104.196.10)
Dear R Team,
Yesterday I downloaded R 0.90.0 and the current versions of some
packages (tseries, quadprog,...).
I had no problems to build the program using FreeBSD 3.2 and SuSe Linux 6.1.
I also re-build all packages required by tseries.
I checked out portfolio.optim (package:
2005 Jun 01
1
Problem with fPortfolio
Hello,
I hesitate to call this a bug, because I could have forgotten something
important, but the MarkowitzPortfolio example in fPortfolio does not work
for me. Here's my code:
> library(fPortfolio)
>
>xmpPortfolio("\nStart: Load monthly data set of returns > ")
> data(berndtInvest)
> # Exclude Date, Market and Interest Rate columns from data
2008 Aug 12
1
fPortfolio constraints, maxsumW
Running R version 2.6.1 under Gentoo Linux and using the fPortfolio
package, I am having trouble specifying a sector constraint. One of the
constraints to be imposed is that assets 1 and 2 together account for no
more than 13.63% of the portfolio. My attempt at coding that
constraint, "maxsumW[1:2Assets]=13.63" fails. The relevant section of
my code file and the resulting error
2018 May 06
1
adding overall constraint in optim()
Hi Michael,
A few comments
1. To add the constraint sum(wgt.vect=1) you would use the method of
Lagrange multipliers.
What this means is that in addition to the w_i (the components of the
weight variables) you would add an additional variable, call it lambda.
Then you would modify your optim.fun() function to add the term
lambda * (sum(wgt.vect - 1)
2. Are you sure that you have defined
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
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
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 Oct 07
1
Testing volatility cluster (heteroscedasticity) in stock return?
Dear All,
i want to use garch model in return of stock. and the data should presence volatility cluster (Heteroscedasticity).
Do you know how to test volatility cluster (the presence of heteroscedasticity) in series data of stock return in R?
Is it using Langrange Multiplier (LM) ARCH test? what package i should use?
I really need the help. Thanks for the attention.
Eko A P
2017 Nov 10
2
R and LINGO?
Hei
Im struggling with this problem:
b) Another company wants to compose the optimal project portfolio based on the following 5-
year project proposals. In the table, the cash flow for each project in each year is shown.
Project 1 Project 2 Project 3 Project 4 Project 5 Project 6
1st year of the project -58 -32 -18 -31 -33 -39
2nd year of the project 17 17 11 4 21 30
3rd year of the project 26 30
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
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
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