An open source programming language and software environment for statistical computing and graphics.

learn more… | top users | synonyms

15
votes
2answers
7k views

How to derive the implied probability distribution from B-S volatilities?

The general problem I have is visualization of the implied distribution of returns of a currency pair. I usually use QQplots for historical returns, so for example versus the normal distribution: ...
20
votes
3answers
2k views

Tools in R for estimating time-varying copulas?

Are there libraries in R for estimating time-varying joint distributions via copulas? Hedibert Lopes has an excellent paper on the topic here. I know there is an existing packaged called copula but ...
18
votes
8answers
6k views

What tools exist for order book analysis and visualization?

What tools exist for order book analysis and visualization? In particular, if one wanted to examine a limit order book and understand how it changes throughout the day where would you turn for ...
7
votes
1answer
15k views

How to interpret results of Johansen Test?

I have two time-series a & b. The objective is to find out whether two series are cointegrated or not. I am using Johansen Test in R to find this out. I am using urca package of R. Here is the ...
7
votes
3answers
16k views

How to fit ARMA+GARCH Model In R?

I am currently working on ARMA+GARCH model using R. I am looking out for example which explain step by step explanation for fitting this model in R. I have time series which is stationary and I am ...
5
votes
1answer
4k views

GARCH model and prediction

I have a question about the prediction of volatility and returns of a time series. Basically it is a question about prediction in the ...
8
votes
1answer
5k views

Forecasting using rugarch package

I want to do one step ahead in-sample forecasts. My data can be found here. This is just a data frame with the date as the rownames. I specify my model and do the fit and show the plots with ...
3
votes
3answers
357 views

Any package to run VAR-GARCH or VECM-GARCH models in R?

I need to estimate a multivariate VECM-GARCH (or simply VAR-GARCH) in R. Browsing on the internet, I did not find anything yet. Do you know if such kind of packages exists? Please, note that a BEKK ...
42
votes
12answers
16k views

Switching from C++ to R - limitations/applications

I've only recently begun exploring and learning R (especially since Dirk recommended RStudio and a lot of people in here speak highly of R). I'm rather C(++) oriented, so it got me thinking - what are ...
5
votes
2answers
2k views

Quantmod: what's the difference between ROC(Cl(SPY)) and ClCl(SPY)

I feel like I'm missing something fundamental here, but I can't shake the feeling that these two series should be equivalent. /edit: there is also dailyReturn(Cl(SPY)). I've seen all 3 of these ...
8
votes
1answer
930 views

Why does the following data fail my cointegration test?

I have some closing price data for two Australian banks which track each other very closely. http://dl.dropbox.com/u/12337149/stat/CBA.csv http://dl.dropbox.com/u/12337149/stat/WBC.csv Code from ...
2
votes
1answer
357 views

short-sale constraint with nonpositive-definite matrix in portfolio optimization

I need help about portfolio optimization in R. I have inverted matrix and I want to use it as an input in portfolio optimization. It was non-positive definite before I have handled it. In portfolio ...
2
votes
2answers
51 views

Problem with obtaining densities

For my research I need to obtain a series of densities, however, I am encountering some problems. The first problem is perhaps very simple, but the answer eludes me. Let's say I have an observation ...
2
votes
0answers
290 views

Any one know how to implement the Heston and Rouwenhorst country-sector effects regression in R?

Heston and Rouwenhorst (1994) devised an empirical estimation strategy to decompose stock returns into three components: a pure industry effect, a pure country effect, and a world-factor return. ...
1
vote
0answers
41 views

Portfolio Optimization with equal weight for assets selected

I have a data frame of bets, with 1 being a win and 0 being a loss. These bets are correlated so I cannot just pick the highest winning percentage. Goal is to get 2 optimizations, 1 for max sharpe ...
1
vote
2answers
102 views

Stochastic process theory question

*S follows a process $dS= mSdt + oSdz$ where m and o are constant. What is the probability followed by $ Y=(Se)^{(r-t)} $. If S follows a process $ dS= k (b-S) dt + oSdz $ where k, b, o are ...
1
vote
1answer
164 views

Is there a good backtesting package in R?

My model exports a vector that have for each day b-buy s-sell or h- hold it's look like this: sig [1] b b s s b b b s s b s b s s b s b s s s s b b s s b b b b b b s b b b b b b b I want to ...
0
votes
1answer
97 views

Constant decreasing volatility, GARCH forecasting

I am trying to forecast the volatility using GARCH modelling in R. I fit an ARMA(1,1)-GARCH(1,1) model, but my sigma predictions are constantly decreasing. Anybody know why? ...