SynthETIC

SynthETIC 1.1.2

Bug fixes

• simulate_covariates() no longer calls set.seed() unconditionally. With the default random_seed = NULL this previously resolved to set.seed(NULL), which reseeds R’s random number generator from system entropy: the covariate levels, and every draw made after them, ignored any seed set by the user and were not reproducible. The caller’s random number stream is now left untouched in this case, so a seed set via set.seed() carries through the whole simulation as expected. Thanks to Patrick Laub (@Pat-Laub, #5).

• When random_seed is supplied to simulate_covariates() or claim_size_adj(), the caller’s random number stream is now saved and restored around the local seeding, instead of being left rewound to that seed. The simulated covariate levels and adjusted claim sizes for a given random_seed are unchanged; only the state of the stream afterwards differs, so subsequent modules (notification, closure, payments) will now draw from the caller’s own stream rather than from one determined by random_seed.

Note on the bundled datasets

The bundled datasets (test_covariates_dataset, test_claims_object_cov, test_claim_dataset_cov and test_transaction_dataset_cov) are unchanged in this release. They were generated before this fix and are therefore not reproducible from data-raw/test_data_covariates.R; they have been left as-is so that existing analyses built on them continue to work. They will be regenerated in a future major release.

SynthETIC 1.1.1

Minor improvements and fixes

• Includes a random seed option to for claims covariate simulation.

SynthETIC 1.1.0

Inclusion of claim_covariates sub-module

• Extends the package by including support for covariates and their impact on claim sizes.

• Includes one new vignette, demonstrating the sub-module and its use-cases.

• Includes five new data objects. The three existing datasets test_claims_object, test_claim_dataset and test_transaction_dataset now also have a version where outputs are impacted by the effect of covariates. A test_covariates_obj and test_covariates_dataset have been included which provide information regarding the specific factors and levels of covariates used in relation to each claim.

Minor improvements and fixes

• Updates citation

SynthETIC 1.0.5

Minor improvements and fixes

• Removes dependency (Suggests) on the poisson package

SynthETIC 1.0.4

Minor improvements and fixes

• Removes dependency (Suggests) on the ChainLadder package

SynthETIC 1.0.3

New features

• Adds plot_transaction_dataset() function for plotting claim development from a payment-level dataset, in addition to the plot.claims method that works only with a claims object.

SynthETIC 1.0.2

Minor improvements and fixes

• Updates citation

• Fixes a bug in the default sampling function of claim_payment_no()

• Fixes the treatment of params_split to allow for trivial params

SynthETIC 1.0.1

New features

• Updates claim_output() to allow an option to adjust the treatment of out-of-bound transactions in tabulation. The previous version (1.0.0) automatically forced all out-of-bound transactions to be paid at the exact end of the maximum development period allowed. This is now set as the default behaviour, but the user can also set adjust = FALSE to see the proportion of payments projected to fall beyond the maximum development period (the “tail”).

Minor improvements and fixes

• Updates claim_output() to force adjust for higher aggregate_level. The issue with previous function was that it ignored payments beyond the max development period after aggregation. This is now fixed - either merged to the end DQ, or in a separate tail cell (if adjust = FALSE).

SynthETIC 1.0.0

New features

• Both claim_frequency() and claim_size() now allow users to input a random generation function (by specifying a simfun and setting type = "r"), in addition to cdf inputs (type = "p") allowed by the predecessor version.

  • Also improves the simulation efficiency. When a cdf is given, the function will first search for the existence of the corresponding r-function and if it finds one, apply the r-function directly instead of inverse sampling from the cdf.

• Relaxes assumptions for claim_notification() and claim_closure().

  • SynthETIC 0.1.0 assumes Weibull and only allows changes to mean and cv.
  • The new version relaxes this assumption and allows user to input any sampling distribution through rfun and paramfun.

• Sets the benchmarks in claim_payment_no() function optional (and will only be read if the default simulation function is used).

• claim_payment_no() is now also implemented through rfun and paramfun, instead of the original simulate_no_pmt_function (which works in the same way as rfun but without the functionality to change parameters).

• claim_payment_size() is also implemented through rfun and paramfun, replacing the original simulate_amt_pmt_function.

• New to_SynthETIC() function helps the conversion from externally simulated objects to SynthETIC format for easy integration with other simulation functions/modules.

Minor improvements and fixes

• Fixed a few typos in function documentation.

• claim_output() function is updated to correctly calculate triangles on a higher aggregate level (from square to parallelogram-shaped).

• The package vignette has been updated to reflect all the changes listed above and show more examples where the quantities are simulated from distributions other than the default.

• The GitHub repo address is added to the DESCRIPTION file.

• The following don’t affect the users of the package:

  • the test_data.R file under data-raw has been updated to reflect the changes listed under the heading “new features”.
  • the DESCRIPTION file has been updated to include the new reference made in the vignette (e.g. actuar).