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pomp: statistical inference for partially-observed Markov processes

pomp version 1.19 is now available on CRAN. Source and binaries will soon be visible on a CRAN mirror near you.

Important note

Version 2 of pomp, with major improvements, is on its way. Because it is not fully backward-compatible, pomp version 2 is being made available temporarily as the pomp2 package. pomp2 is not available on CRAN but source and binaries can be downloaded from the pomp website. See the installation page for instructions.

pomp2 will be phased out, replaced by version 2 of pomp, around the middle of 2019. At that point, pomp versions <2 will no longer be supported.

It is recommended that users begin making the transition to version 2 now. An upgrade guide is available to help you transition your codes to the new version. In the interim period, you can have both pomp and pomp2 installed on your system simultaneously.

Release notes

pomp version 1.19 includes bug fixes and some feature enhancements.

User-visible changes

• show and print methods have been made very terse: they simply report on the class of the object in question. To see more detailed information about a pomp object, use spy.
• New verbose option in trajectory gives diagnostic information from deSolve integration routines. Of course, this is pertinent only if the model skeleton is a vectorfield.
• coef(object) <- NULL, where object is of class pomp, erases any parameters stored in object.
• The obs and states arguments of simulate are deprecated and will be removed in a forthcoming release.
• The old forward and inverse options for the dir argument of partrans have been dispensed with. The much more descriptive options toEstimationScale and fromEstimationScale remain.
• The euler.sir, gillespie.sir, blowflies, ricker, bbs, dacca, and rw2 examples are all now implemented using C snippets.
• The handling of dprocess has changed. The onestep.dens plugin is now deprecated and will soon be removed. dprocess is now specified directly using either a C snippet or an R function, in much the same way that, for example, dmeasure is specified.
• A bug in pfilter (and hence pmcmc) when filter.traj=TRUE was discovered and fixed. In the buggy version, the filter trajectory was sampled with incorrect weights.
• A bug in the display of istate when deSolve::ode errors has been fixed.
• Timo Voipio contributed a pull request that traps the error resulting from sannbox being passed a candidate.dist that is not a function.

API and implementation changes

• The C-level interface for apply_probe_sims has changed: the new argument rho must be the "package:pomp" environment.
• New (unexported) solibs<- method allows developers of packages extending pomp to incorporate C snippets into object that contain pomp objects.
• New hitch function facilitates construction of pomp.fun objects from R functions, C snippets, and links to external libraries.
• Native routines needed to access pomp.fun objects in C are now registered for use by other packages.
• A new pomp_defines.h header is provided for developers of packages that depend on pomp.
• Internally, rprocess is no longer stored as an R function. The use of plugins is now required for the implementation of the rprocess component. Currently, there are five plugins available: onestep.sim, discrete.time.sim, euler.sim, gillespie.sim, and gillespie.hl.sim.
• The C snippet compiling facilities have been thoroughly reworked.

See the package NEWS for more details.

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