News

Changes in Version 1.3.3:

• Registered native routines.
• Workaround for typo appearing in conversion of help files to LaTeX document. Thanks to Evelyn Mitchell for pointing this out.

Changes in Version 1.3.2:

• Some more changes in the AWOL sampler because version 1.3.1 appeared to be unstable under Solaris: Sampling of h (including h0) is now done AWOL.
• Turned progress indicator off again (not sure whether this causes issues with Solaris).

Changes in Version 1.3.1:

• Parameter starting values are now set to their respective prior means (if not specified by the user).
• Sampling h[-0] is now done conditionally on h0. This change should not make a difference for the standard use cases of stochvol but is necessary to yield correct results for the new prior for h0 which was introduced in version 1.3.0.
• Turned on progress indicator also for Windows (need %% instead of \045 or % to escape a percent symbol in Rprintf).

Changes in Version 1.3.0:

• Implemented new prior for initial log-volatility h0. Can be used to stabilize the level of the volatilities, especially when stochvol is used within the context of a more general MCMC algorithm.
• Shortened the heavytails-vignette (a bit) to stay below the 5MB mark.
• Fixed error in help files of svsample and svsample2 concerning startpara. Thanks to Dominic Cervicek for pointing this out.

Changes in Version 1.2.4:

• Fixed typo which appeared in pdf package documentation. Thanks to Stefan Voigt for pointing this out.

Changes in Version 1.2.3:

• Updated CITATION to cater for newly published article in the Journal of Statistical Software 69(5), 1-30, doi: 10.18637/jss.v069.i05.
• The function logret can now handle xts objects. Thanks to Niko Hauzenberger for pointing this out.

Changes in Version 1.2.2:

• Fixed bug in initialization of svsample2 that was introduced in 1.2.1. Thanks to John Kerpel for pointing this out.

Changes in Version 1.2.1:

• Added option 'keeptau' to the store the "variance inflation factors" used for the sampler with conditional t innovations. Thanks to Sergey Egiev for pointing out that this may be useful to at what point(s) in time the normal disturbance had to be "upscaled" by a mixture factor and when the series behaved "normally".
• Fixed residuals.svdraws to cater for a potential 'designmatrix'.

Changes in Version 1.2.0:

• Allows for incorporation of a simple mean (regression-type) model. For details, please see ?svsample and ?arpredict. And, hopefully soon, the corresponding vignette.
• Improved input-checking (somewhat).
• Argument 'thintime' in svsample may now also be 'firstlast', meaning that latent volatility draws are only kept for the first and the last point in time.

Changes in Version 1.1.4:

• Included non-base default packages that are imported in NAMESPACE into DESCRIPTION. Thanks to Kurt Hornik for pointing this out.

Changes in Version 1.1.3:

• Fixed a typo in Makefile for building vignettes.

Changes in Version 1.1.2:

• Fixed missing imports from non-base default packages.

Changes in Version 1.1.1:

• Fixed "uninitialized variable" in function newtonRaphson (progutils.cpp). Warning appeared when building for Windows.
• Minor changes in main vignette (article.Rnw) so that the included plots have smaller file size and the package does not exceed the 5MB limit (was the case on r-patched-solaris-sparc).

Changes in Version 1.1.0:

• Introduced sampling and simulating conditional t-innvoations. (Hopefully) all affected functions
  • svsample
  • svsample2
  • volplot
  • paratraceplot
  • paradensplot
  • plot.svdraws
  • plot.svresid
  • svsim
  • updatesummary
  • predict.svdraws
  • residuals.svdraws
  • print.svsim
  • print.summary.svsim
  • print.summary.svdraws and the corresponding help files have been adapted. See package vignette "heavytails" for details. Still a "beta-feature", please use with care. Bug reports and/or comments are warmly welcome!
• The plot functions now take an optional svsim object.
• predict.svdraws is now in R/utilities_svdraws.R (was in R/plotting.R)

Changes in Version 1.0.2:

• Fixed some more typos.
• Plotting functions are now in R/plotting.R

Changes in Version 1.0.1:

• Updated keywords in vignette.
• Changed VignetteKeyword entries to adhere to CRAN style guide.

Changes in Version 1.0.0:

• First stable release.
• Minor stylistic changes in package vignette.
• Updated CITATION file.
• Version numbering changed from X.Y-Z to X.Y.Z.

Changes in Version 0.9-2:

• Fixed some typographical errors in help files. Thanks to Angela Bitto for pointing these out.

Changes in Version 0.9-1:

• Fixed typographical errors in vignette.
• Added additional results in Table 1 of vignette.
• Minor changes in DESCRIPTION to adhere to CRAN style guide.

Changes in Version 0.9-0:

• Requires now Rcpp >= 0.11.0 and consequently R >= 3.0.0.
• Replaced RNGScope in sampler.cpp by "manual" GetRNGstate() and PutRNGstate() statements because the former is not safe if return variables are declared afterwards, cf. https://www.mail-archive.com/[email protected]/msg07519.html and follow-ups for further information.
• Minimal overhead sampling function .svsample was renamed to svsample2. The former name will be faded out; please use svsample2 from now on.
• Substantial rewrite of vignette, especially Section 5; includes now a comparison of SV and GARCH.
• Updates and corrections in .Rd files.
• Added some info when package is attached.
• Sample size is now denoted as "n" instead of "T", in order to avoid confusion with "TRUE" and/or the transpose symbol.

Changes in Version 0.8-4:

• Fixed a bug introduced in version 0.8-2, where I forgot to let .svsample know about the changes in update(...). Thanks to Keiran Thompson for pointing this out.
• Updated CITATION file.

Changes in Version 0.8-3:

• Minor changes in vignette.

Changes in Version 0.8-2

• update(...) now takes an additional boolean argument preventing an update of mu (but instead hold mu = 0 fixed). This feature is needed e.g. for factor stochastic volatility models.
• C++ function "update" rewritten to use ordinary pointers instead of Rcpp objects. This became necessary because Rcpp objects cannot be constructed re-using memory due to the SEXPREC structure. See https://www.mail-archive.com/[email protected]/msg06811.html and follow-ups for a more detailed explanation.

Changes in Version 0.8-1

• Added a -I directive for compiler in Makevars.win so that winbuilder finds headers in inst/include/.
• Re-ran all code used in vignette.

Changes in Version 0.8-0

• Re-structured main sampler code in sampler.cpp: new function "update" performs a single MCMC iteration. Additionally, this function is also made available to be called by C/C++ code in another package. To use this function within C/C++ code, simply #include <update.h> (defined in inst/include) in the C/C++ code of your package, which itself Imports:/Depends: stochvol (>= 0.8). See package factorstochvol for an example using this mechanism.
• Minor stylistic changes in helper functions and subroutines at C++-level).
• Fixed a minor bug in sampler.cpp where regressionNoncentered returned sigma instead of fabs(sigma) when phi is drawn outside of the unit sphere.
• Fixed DESCRIPTION to Import: Rcpp (instead of Depend:).
• Fixed NAMESPACE: Now has "importFrom(Rcpp, evalCpp)" as required by Rcpp 0.11.0.

Changes in Version 0.7-2

• Updated CITATION file.
• Updated vignette (mainly stylistic changes).

Changes in Version 0.7-1

• Manual is now provided as a vignette.

Changes in Version 0.7-0

• Added a manual.
• Changed the default prior for mu from c(-10, 3) to c(0, 100) to avoid disaster when percentage log-returns (instead of log-returns) are used but the prior is not adapted accordingly.
• Included the date in the exrates dataset.
• Changed svsample to also accept vectors with zero-returns; it throws a warning now (instead of an error) and adds an offset constant.
• Fixed plot.svdraws to reset par to old values.
• Added a "residual plot" feature. Thanks to Hedibert Lopes for pointing this out.
• Added the convenience function "logret" for taking log-returns of a given series, with the possibility of de-meaning.
• Cleaned up summary.svdraws, which now returns a "summary.svdraws" object. For actual printing, print.summary.svdraws is used.
• Cleaned up summary.svsim, which now returns a "summary.svsim" object. For actual printing, print.summary.svsim is used.

Changes in Version 0.6-1

• Fixed typo in wrapper.R which previously disallowed changing the "expert" argument "proposalvar4sigmaphi": Replaced "proposalvar2sigmaphi" by "proposalvar4sigmaphi" on line 76.
• Included EUR exchange rates from the European Bank's Statistical Data Warehouse. Use with "data(exrates)".
• Added CITATION file.
• Replaced Rprintf by REprintf and cat(...) by cat(..., file=stderr()) for status reports. Thanks to Kurt Hornik for pointing this out.

Changes in Version 0.6-0

• Introduced ".svsample" for minimal overhead sampling. Intended to be used as a plug-in into other MCMC samplers. No input checking, use with proper care!
• Disabled progress bar in non-Unix-like systems due to problems with console flushing.
• Some bug fixes for solaris. Seems to build fine now. Thanks to Brian Ripley for reporting the bugs.

Changes in Version 0.5-1

• Replaced all paste0(...) calls by paste(..., sep='') for compatibility reasons.

Changes in Version 0.5-0

• First CRAN release version.

TODO:

• Code updatesummary in C (apply w/ quantiles is slow).
• Make AWOL sampler available for fixed parameters. Thanks to Hedibert Lopes for pointing this out.

Reference manual